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3D Printing I 020516 3d_printing

The specter of counterfeit products is always a concern for any company that relies on other facilities to actually manufacture and assemble their products. From fake Rolex watches to fake iPhones to fake Louis Vuitton purses, large companies often spend millions to protect their intellectual property from criminals who copy and sell fake products to often unsuspecting consumers.

While it can be easy to be anti-corporate and turn a blind eye to this kind of theft, especially when the companies are large and extremely profitable, their concern goes far beyond the potential loss of profits. The fact is, most counterfeit products are vastly inferior to the real thing, and if a consumer doesn’t know that they are purchasing a fake then the company not only has a lost sale, but their reputation will take a hit based on something that they didn’t even produce.

Even as 3D printing continues to grow into a valid and profitable alternative manufacturing method to injection molding or large-scale mass production, there are still companies that see the threat of counterfeiting as a reason to stall the adoption of 3D printing technology. Realistically there is not much that can be done about pirated 3D models and individuals using home 3D printers to make fake products. Combating individual piracy has been woefully ineffective for the entertainment industry, and probably only encouraged more users to download electronic files illegally. It stands to reason that going after individual pirates will work just as well if the 3D printing industry makes an attempt to over-regulate and control the flow of 3D printable files.

DRM on 3D printable files is probably not going to be an effective deterrent.

DRM on 3D printable files is probably not going to be an effective deterrent.

Many of the solutions that are being floated as counter-counterfeiting measures don’t really seem especially feasible or sustainable. Adding DRM (digital rights management) or unlock code requirements to 3D files may slow down some users, but just as with DRM efforts on movies and video games, if someone can put a lock on something, someone can take that same lock off and teach others how to do it as well. These efforts may work in the short term, as the pool of users who are capable of breaking DRM on 3D printable files is smaller, and there isn’t really an outlet to disperse those illegal files yet. But as the industry grows it is going to be harder and harder for companies to control their intellectual property using these methods. I’m not really sure that there is much to be done on this end of the industry. Besides, there is an even greater counterfeiting problem brewing on the manufacturing side of the industry and it is far more important than individual piracy ever could be.

Counterfeit bolts.

Counterfeit bolts.

As with fake mass-produced consumer goods, mass-produced industrial parts are also counterfeited quite frequently. It may be more interesting to talk about fake purses, but a greater threat is products like fake screws, bolts, fittings and individual components. Many of the parts that are used to build our homes, businesses, vehicles and personal electronics use mass-produced components that manufacturers simply purchase in extremely large quantities. And all of those parts are held to very strict manufacturing guidelines that dictate how they can be used, what their maximum stress tolerances are and how they can be expected to perform.

When these types of components are forged, they are rarely made with the same quality of materials and often don’t even come close to performing as required. If these fake parts find their way unknowingly into the hands of manufacturers, who design products with these components’ manufacturing guidelines in mind, then the results could be catastrophic. There have been instances of airplanes and automobiles that have crashed due to the failure of lower quality, counterfeit parts. Buildings and homes are also at risk due to poor quality and counterfeited construction materials being used. It may seem odd, but cheaply made products that do not pass strict regulations are a huge business and lives can be lost to it.

3D printed Nike shoes with embedded InfraStructs.

3D printed Nike shoes with embedded InfraStructs.

With 3D printed components becoming more common, and eventually expected to be extremely common, counterfeit parts will pose a real risk. Using DRM, even if it was effective on a small scale, to prevent machines from making unauthorized parts is not going to matter when these parts can simply be 3D scanned and reproduced without the need for the original 3D model. The methods that need to be developed to combat this type of industrial counterfeiting will need to work in ways that DRM never will and identify the specific physical object as authentic. There are a few different methods that are currently being proposed, with varying probabilities of success.

The most likely option will be including RFID tags on 3D printed components that will identify an object as the real thing. The idea is that any part that doesn’t have an embedded RFID device in it — and they can easily be made small enough to easily be inserted inside of a 3D printed part — will automatically be identified as fake. The downside of this method is price, as the RFID tags themselves would be costly, as would the labor involved in inserting them. Testing for tags will also require specialized equipment that adds more cost to the authentication process. It is possible that a 3D printable material that would act as a tag called InfraStructs could be developed, but that would mean developing multiple materials that will be RFID reactive, which will be quite costly on the development side.

Subsurface fingerprinting with InfraTrac.

Subsurface fingerprinting with InfraTrac.

Another authentication option would be chemically tagging materials that can be detected with a handheld spectrometer. There are multiple companies providing these types of materials, but the most promising is a technique developed by InfraTrac. The Maryland-based company has developed a chemical that can be discreetly added to virtually anything without altering the chemical makeup of the material. For instance, parts can be 3D printed with a small subsurface “fingerprint” hidden in a discrete location. That mark alone would be printed with the material that has been treated with the chemical, and would easily identify the part as genuine. The material could also be printed as a single layer of the print with no mark, and no risk of altering the integrity of the part. Of course again this comes with it the need for specialized equipment in the form of the spectrometer and an actual machine that can 3D print with the standard material and the second, tagged material.

3D Printing II Heart 020516 maxresdefault

3D Printed Model of a Human Heart

One thing is very clear, there is a desire for additive manufacturing to be developed as an alternative to other mass production methods. That means the companies looking to use 3D printing to manufacture parts, and the 3D printing industry itself, are going to need to address the problem sooner rather than later. Determining which of these options is the ideal solution will not be an easy choice, as they both bring with them additional costs and challenges, but doing nothing simply isn’t an option.

 

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Nanowires 020316 bf8802f7297fd2bfea985c26d0b9a636_w1440

California is committed to 33 percent energy from renewable resources by 2020. With that deadline fast approaching, researchers across the state are busy exploring options.

Solar energy is attractive but for widespread adoption, it requires transformation into a storable form. This week in ACS Central Science, researchers report that nanowires made from multiple metal oxides could put solar ahead in this race.

One way to harness solar power for broader use is through photoelectrochemical (PEC) water splitting that provides hydrogen for fuel cells. Many materials that can perform the reaction exist, but most of these candidates suffer from issues, ranging from efficiency to stability and cost.

Peidong Yang and colleagues designed a system where nanowires from one of the most commonly used materials (TiO2) acts as a “host” for “guest” nanoparticles from another oxide called BiVO4. BiVO4 is a newly introduced material that is among the best ones for absorbing light and performing the water splitting reaction, but does not carry charge well while TiO2 is stable, cheap and an efficient charge carrier but does not absorb light well.

Together with a unique studded nanowire architecture, the new system works better than either material alone.

The authors state their approach can be used to improve the efficiencies of other photoconversion materials.

Synopsis

We report the use of Ta:TiO2|BiVO4 as a photoanode for use in solar water splitting cells. This host−guest system makes use of the favorable band alignment between the two semiconductors. The nanowire architecture allows for simultaneously high light absorption and carrier collection for efficient solar water oxidation.

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Metal oxides that absorb visible light are attractive for use as photoanodes in photoelectrosynthetic cells. However, their performance is often limited by poor charge carrier transport. We show that this problem can be addressed by using separate materials for light absorption and carrier transport. Here, we report a Ta:TiO2|BiVO4 nanowire photoanode, in which BiVO4 acts as a visible light-absorber and Ta:TiO2 acts as a high surface area electron conductor. Electrochemical and spectroscopic measurements provide experimental evidence for the type II band alignment necessary for favorable electron transfer from BiVO4 to TiO2. The host–guest nanowire architecture presented here allows for simultaneously high light absorption and carrier collection efficiency, with an onset of anodic photocurrent near 0.2 V vs RHE, and a photocurrent density of 2.1 mA/cm2 at 1.23 V vs RHE.

Introduction


Harnessing energy from sunlight is a means of meeting the large global energy demand in a cost-effective and environmentally benign manner. However, to provide constant and stable power on demand, it is necessary to convert sunlight into an energy storage medium.(1) An example of such a method is the production of hydrogen by photoelectrochemical (PEC) water splitting. The direct splitting of water can be achieved using a single semiconductor; however, due to the voltage requirement of the water splitting reaction and the associated kinetic overpotentials, only wide-band-gap materials can perform overall water splitting, limiting the efficiency due to insufficient light absorption.(2) To address this issue, a dual-band-gap z-scheme system can be utilized, with a semiconductor photoanode and photocathode to perform the respective oxidation and reduction reactions.(3) This approach allows for the use of lower-band-gap materials that can absorb complementary portions of the solar spectrum and yield higher solar-to-fuel efficiencies.(4, 5) In this integrated system, the charge flux is matched in both light absorbers of the photoelectrochemical cell. Therefore, the overall performance is determined by the limiting component. In most photoelectrosynthetic cells, this limiting component is the semiconductor photoanode.(6)
Metal oxides have been heavily researched as photoanode materials since few conventional light absorber materials are stable at the highly oxidizing conditions required for water oxidation.(7) However, the most commonly studied binary oxide, TiO2, has a band gap that is too large to absorb sunlight efficiently (∼3.0 eV), consequently limiting its achievable photocurrent.(8) While promising work has recently been done on stabilizing conventional light absorbers such as Si,(9) GaAs,(10) and InP,(11) the photovoltage obtained by these materials thus far has been insufficient to match with smaller-band-gap photocathode materials such as Si and InP in a dual absorber photoelectrosynthetic cell.(12, 13) Additionally, these materials have high production and processing costs. Small-band-gap metal oxides that absorb visible light and can be inexpensively synthesized, such as WO3, Fe2O3, and BiVO4, are alternative materials that hold promise to overcome these limitations.(14-16) Among these metal oxides, BiVO4 has emerged as one of the most promising materials due to its relatively small optical band gap of ∼2.5 eV and its negative conduction band edge (∼0 V versus RHE).(17, 18) Under air mass 1.5 global (AM1.5G) solar illumination, the maximum achievable photocurrent for water oxidation using BiVO4 is ∼7 mA/cm2.(16) However, the water oxidation photocurrent obtained in practice for BiVO4 is substantially lower than this value, mainly due to poor carrier transport properties, with electron diffusion lengths shorter than the film thickness necessary to absorb a substantial fraction of light.(17)
One approach for addressing this problem is to use two separate materials for the tasks of light absorption and carrier transport. To maximize performance, a conductive and high surface area support material (“host”) is used, which is coated with a highly dispersed visible light absorber (“guest”). This architecture allows for efficient use of absorbed photons due to the proximity of the semiconductor liquid junction (SCLJ). This strategy has been employed in dye sensitized (DSSC) and quantum dot sensitized solar cells (QDSSC).(19, 20) Using a host–guest scheme can improve the performance of photoabsorbing materials with poor carrier transport but relies upon appropriate band alignment between the host and guest. Namely, the electron affinity of the host should be larger, to favor electron transfer from guest to host without causing a significant loss in open-circuit voltage.(21) Nanowire arrays provide several advantages for use as the host material as they allow high surface area loading of the guest material, enhanced light scattering for improved absorption, and one-dimensional electron transport to the back electrode.(22) Therefore, nanowire arrays have been used as host materials in DSSCs, QDSSCs, and hybrid perovskite solar cells.(23-25) In photoelectrosynthetic cells, host–guest architectures have been utilized for oxide photoanodes such as Fe2O3|TiSi2,(26) Fe2O3|WO3,(27) Fe2O3|SnO2,(28) and Fe2TiO5|TiO2.(29) For BiVO4, it has been studied primarily with WO3|BiVO4,(30-32) ZnO|BiVO4,(33) and anatase TiO2|BiVO4.(34) While attractive for its electronic transport properties, ZnO is unstable in aqueous environments, and WO3 has the disadvantage of having a relatively positive flatband potential (∼0.4 V vs RHE)(14) resulting in potential energy losses for electrons as they are transferred from BiVO4 to WO3, thereby limiting the photovoltage of the combined system. Performance in the low potential region is critical for obtaining high efficiency in photoelectrosynthetic cells when coupled to typical p-type photocathode materials such as Si or InP.(12, 13) TiO2 is stable in a wide range of pH and has a relatively negative flat band potential (∼0.2 V vs RHE)(7) which does not significantly limit the photovoltage obtainable from BiVO4, while still providing a driving force for electron transfer. While TiO2 has intrinsically low mobility, doping TiO2 with donor type defects could increase the carrier concentration and thus the conductivity. Indeed, niobium and tantalum doped TiO2 have recently been investigated as potential transparent conductive oxide (TCO) materials.(35, 36) A host material with high carrier concentration could also ensure low contact resistance with the guest material.(37)
Using a solid state diffusion approach based on atomic layer deposition (ALD), we have previously demonstrated the ability to controllably and uniformly dope TiO2.(38) In this study we demonstrate a host–guest approach using Ta-doped TiO2 (Ta:TiO2) nanowires as a host and BiVO4 as a guest material. This host–guest nanowire architecture allows for simultaneously high light absorption and carrier collection efficiency, with an onset of anodic photocurrent near 0.2 V vs RHE, and a photocurrent of 2.1 mA/cm2 at 1.23 V vs RHE. We show that the synergistic effect of the host–guest structure results in higher performance than either pure TiO2 or BiVO4. We also experimentally demonstrate thermodynamically favorable band alignment between TiO2 and BiVO4 using spectroscopic and electrochemical methods, and study the band edge electronic structure of the TiO2 and BiVO4 using X-ray absorption and emission spectroscopies.

Article adapted from a American Chemical Society news release. To Read the FULL release, please click on the link provided below.

Publication: TiO2/BiVO4 Nanowire Heterostructure Photoanodes Based on Type II Band Alignment. Resasco, J et al. ACS Central Science (3 February, 2016): Click here to view.

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Sun Solar 061015 Fusion BBkFITY

Video Interview with Professor Ted Sargent at the University of Toronto

With global climate change on the rise, finding ways to capture renewable energy sources is becoming more urgent. Today, our energy needs are largely being met by fossil fuels, such as oil and coal, but we are rapidly depleting these natural resources, and damaging our environment by burning them for fuel. One sustainable alternative is solar energy. Prof. Ted Sargent, an electrical engineer at the University of Toronto, is working on making a new paint-based solar cell that would be low-cost, lightweight, portable, and efficient, bringing sustainable electricity anywhere that it is needed.

We picture a world in which solar cells are so convenient. They are on a carpet that you can roll out onto your roof, or they are on a decal that you can stick on the side of a streetcar or stick on your car, you can stick on your airplane wing. And they can be kind of adhered to any surface. And they can be used to meet the power needs of that automobile or plane or helicopter or home or tent; and they are ubiquitous.

Unlike fossil fuels, Sargent explains, “the sun is this incredible, vast resource. We get more sun reaching the Earth’s surface everyday than we need to power the world’s energy needs. In fact, in an hour, we get enough to meet our energy needs for a year; it’s that abundant.” To achieve a better solar cell, Prof. Sargent is working at the interface of chemistry, physics, materials science, and electrical engineering to understand the relationships between light and electrons. He is developing a liquid for solar capture that can be applied as a paint, and that can be printed using roll-to-roll processes similar to those used to print newspapers. These paints would absorb sunlight and use it to generate electricity.

Prof. Sargent envisions solar cells that are so minimal that installing one might be as simple as unrolling a sheet onto a rooftop, or applying a decal to a streetcar or phone. “We picture a world in which solar cells are so convenient… They are so little in their consumption of materials that we change the paradigm of solar energy from one that takes planning, major capital investment, to one where it’s all over the place because it’s so compelling and convenient,” says Sargent.

How do you envision the future of energy and power? Let us know in the comments.


Prof. Ted Sargent
Prof. Ted Sargent holds the Canada Research Chair in Nanotechnology at the University of Toronto, where he also serves as Vice Dean for Research for the Faculty of Applied Science and Engineering. He is a Fellow of the Royal Society of Canada, a Fellow of the AAAS “for distinguished contributions to the development of solar cells and light sensors based on solution-processed semiconductors” and a Fellow of the IEEE “for contributions to colloidal quantum dot optoelectronic devices.” He is CTO of InVisage Technologies of Menlo Park, CA; and is a co-founder of Xagenic Inc.

QD Images Scale and Size quantum_dots_c

 

Readers’ Note: Dr. Alivisatos (Berkeley) has been a pioneer of ‘nano-cystals’ and their potential applications. Most recently these ‘crystals’ or Quantum Dots have found their way into commercial application for Display Screens. However the much larger vision for QD’s has significant (“game changing”) implications for: Solar Energy, Bio-Medicine, Drug Theranostics & Delivery, Lighting and Hybrid-Materials (Coatings, Paints, Security Inks as examples).  Enjoy the Video ~ Team GNT

Nanosys scientific co-founder and Director of the Lawerence Berkeley National Lab, Dr. Paul Alivisatos, takes NBC Learn on a tour of Nanosys’ Silicon Valley Quantum Dot manufacturing facility.

The section on Nanosys begins at 2:16 – enjoy!

Watch: NanoSys: Quantum Dot Video

Dr Alivisatos, who recently received the 2016 National Medal of Science, talks with NBC reporter Kate Snow about how this amazing nanotechnology that he helped pioneer is changing the way our TVs work today:

SNOW: When quantum dots of different sizes are grouped together by the billions, they produce vivid colors that have changed the way we look at display screens. The initial research, funded by the NSF, has found its way into many applications, including a nanotechnology company called Nanosys, which produces 25 tons of quantum dot materials every year, enough for approximately 6 million 60 inch TVs.

ALIVISATOS: What we have here is a plastic film that contains inside of it quantum dots, very tiny, tiny crystals made out of semiconductors. It actually contains two sizes of nanoparticle – a very small size that emits a green color and a slightly larger size that emits a red color of light.

SNOW: This film is embedded into tablets, televisions, and laptops to enhance their displays with brilliant color.

ALIVISATOS: One of the things that we’ve learned about vision is that we have receptors in our eyes for green, red and blue colors. And if we want a really high quality display, we need to match the light emission from our display to the receptors in our eyes.

Tour De Ice graphenecomp

Rice University scientists embedded graphene nanoribbon-infused epoxy in a section of helicopter blade to test its ability to remove ice through Joule heating. Credit: Tour Group/Rice University 

A thin coating of graphene nanoribbons in epoxy developed at Rice University has proven effective at melting ice on a helicopter blade.

The coating by the Rice lab of chemist James Tour may be an effective real-time de-icer for aircraft, , transmission lines and other surfaces exposed to winter weather, according to a new paper in the American Chemical Society journal ACS Applied Materials and Interfaces.

In tests, the lab melted centimeter-thick ice from a static helicopter rotor blade in a minus-4-degree Fahrenheit environment. When a small voltage was applied, the coating delivered electrothermal heat – called Joule heating – to the surface, which melted the ice.

The nanoribbons produced commercially by unzipping nanotubes, a process also invented at Rice, are highly conductive. Rather than trying to produce large sheets of expensive graphene, the lab determined years ago that nanoribbons in composites would interconnect and conduct electricity across the material with much lower loadings than traditionally needed.

Previous experiments showed how the nanoribbons in films could be used to de-ice radar domes and even glass, since the films can be transparent to the eye.

Graphene composite may keep wings ice-free
Lab tests at Rice University on a section of a helicopter rotor chilled to minus-4 degrees Fahrenheit show that a thin coat of nanoribbon-infused epoxy can be used as a de-icer. The composite, imbedded between an abrasion shield and the …more

“Applying this composite to wings could save time and money at airports where the glycol-based chemicals now used to de-ice aircraft are also an environmental concern,” Tour said.

In Rice’s lab tests, nanoribbons were no more than 5 percent of the composite. The researchers led by Rice graduate student Abdul-Rahman Raji spread a thin coat of the composite on a segment of rotor blade supplied by a helicopter manufacturer; they then replaced the thermally conductive nickel abrasion sleeve used as a leading edge on . They were able to heat the composite to more than 200 degrees Fahrenheit.

For wings or blades in motion, the thin layer of water that forms first between the heated composite and the surface should be enough to loosen ice and allow it to fall off without having to melt completely, Tour said.

The lab reported that the remained robust in temperatures up to nearly 600 degrees Fahrenheit.

As a bonus, Tour said, the coating may also help protect aircraft from lightning strikes and provide an extra layer of electromagnetic shielding.

Explore further: Researchers create sub-10-nanometer graphene nanoribbon patterns

More information: Abdul-Rahman O. Raji et al. Composites of Graphene Nanoribbon Stacks and Epoxy for Joule Heating and Deicing of Surfaces, ACS Applied Materials & Interfaces (2016). DOI: 10.1021/acsami.5b11131

Nano Weaving RD_COF

There are many different ways to make nano-materials but weaving, the oldest and most enduring method of making fabrics, has not been one of them – until now. An international collaboration led by scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley, has woven the first three-dimensional covalent organic frameworks (COFs) from helical organic threads. The woven COFs display significant advantages in structural flexibility, resiliency and reversibility over previous COFs – materials that are highly prized for their potential to capture and store carbon dioxide then convert it into valuable chemical products.

“We have taken the art of weaving into the atomic and molecular level, giving us a powerful new way of manipulating matter with incredible precision in order to achieve unique and valuable mechanical properties,” says Omar Yaghi, a chemist who holds joint appointments with Berkeley Lab’s Materials Sciences Division and UC Berkeley’s Chemistry Department, and is the co-director of the Kavli Energy NanoScience Institute (Kavli-ENSI).

“Weaving in chemistry has been long sought after and is unknown in biology,” Yaghi says. “However, we have found a way of weaving organic threads that enables us to design and make complex two- and three-dimensional organic extended structures.”

Yaghi is the corresponding author of a paper in Science reporting this new technique. The paper is titled “Weaving of organic threads into a crystalline covalent organic framework.” The lead authors are Yuzhong Liu, Yanhang Ma and Yingbo Zhao. Other co-authors are Xixi Sun, Felipe Gándara, Hiroyasu Furukawa, Zheng Liu, Hanyu Zhu, Chenhui Zhu, Kazutomo Suenaga, Peter Oleynikov, Ahmad Alshammari, Xiang Zhang and Osamu Terasaki.

COFs and their cousin materials, metal organic frameworks (MOFs), are porous three-dimensional crystals with extraordinarily large internal surface areas that can absorb and store enormous quantities of targeted molecules. Invented by Yaghi, COFs and MOFs consist of molecules (organics for COFs and metal-organics for MOFs) that are stitched into large and extended netlike frameworks whose structures are held together by strong chemical bonds. Such frameworks show great promise for, among other applications, carbon sequestration.

Through another technique developed by Yaghi, called “reticular chemistry,” these frameworks can also be embedded with catalysts to carry out desired functions: for example, reducing carbon dioxide into carbon monoxide, which serves as a primary building block for a wide range of chemical products including fuels, pharmaceuticals and plastics.

In this latest study, Yaghi and his collaborators used a copper(I) complex as a template for bringing threads of the organic compound “phenanthroline” into a woven pattern to produce an immine-based framework they dubbed COF-505. Through X-ray and electron diffraction characterizations, the researchers discovered that the copper(I) ions can be reversibly removed or restored to COF-505 without changing its woven structure. Demetalation of the COF resulted in a tenfold increase in its elasticity and remetalation restored the COF to its original stiffness.

“That our system can switch between two states of elasticity reversibly by a simple operation, the first such demonstration in an extended chemical structure, means that cycling between these states can be done repeatedly without degrading or altering the structure,” Yaghi says. “Based on these results, it is easy to imagine the creation of molecular cloths that combine unusual resiliency, strength, flexibility and chemical variability in one material.”

Yaghi says that MOFs can also be woven as can all structures based on netlike frameworks. In addition, these woven structures can also be made as nanoparticles or polymers, which means they can be fabricated into thin films and electronic devices.

“Our weaving technique allows long threads of covalently linked molecules to cross at regular intervals,” Yaghi says. “These crossings serve as points of registry, so that the threads have many degrees of freedom to move away from and back to such points without collapsing the overall structure, a boon to making materials with exceptional mechanical properties and dynamics.”

Source: Lawrence Berkeley National Laboratory

Nano Hydrogen 012216 iuscientists

Scientists at Indiana University have created a highly efficient biomaterial that catalyzes the formation of hydrogen—one half of the “holy grail” of splitting H2O to make hydrogen and oxygen for fueling cheap and efficient cars that run on water.

A modified enzyme that gains strength from being protected within the protein shell—or “capsid”—of a bacterial virus, this new material is 150 times more efficient than the unaltered form of the enzyme.

The process of creating the material was recently reported in “Self-assembling biomolecular catalysts for hydrogen production” in the journal Nature Chemistry.

“Essentially, we’ve taken a virus’s ability to self-assemble myriad genetic building blocks and incorporated a very fragile and sensitive enzyme with the remarkable property of taking in protons and spitting out hydrogen gas,” said Trevor Douglas, the Earl Blough Professor of Chemistry in the IU Bloomington College of Arts and Sciences’ Department of Chemistry, who led the study. “The end result is a virus-like particle that behaves the same as a highly sophisticated material that catalyzes the production of hydrogen.”

Other IU scientists who contributed to the research were Megan C. Thielges, an assistant professor of chemistry; Ethan J. Edwards, a Ph.D. student; and Paul C. Jordan, a postdoctoral researcher at Alios BioPharma, who was an IU Ph.D. student at the time of the study.

IU scientists create 'nano-reactor' for the production of hydrogen biofuel
Illustration showing the release of NiFe-hydrogenase from inside the virus shell, or ‘capsid’, of bacteriophage P22. Credit: Indiana University

The genetic material used to create the enzyme, hydrogenase, is produced by two genes from the common bacteria Escherichia coli, inserted inside the protective capsid using methods previously developed by these IU scientists. The genes, hyaA and hyaB, are two genes in E. coli that encode key subunits of the hydrogenase enzyme. The capsid comes from the known as bacteriophage P22.

The resulting biomaterial, called “P22-Hyd,” is not only more efficient than the unaltered enzyme but also is produced through a simple fermentation process at room temperature.

The material is potentially far less expensive and more environmentally friendly to produce than other materials currently used to create fuel cells. The costly and rare metal platinum, for example, is commonly used to catalyze hydrogen as fuel in products such as high-end concept cars.

“This material is comparable to platinum, except it’s truly renewable,” Douglas said. “You don’t need to mine it; you can create it at room temperature on a massive scale using fermentation technology; it’s biodegradable. It’s a very green process to make a very high-end sustainable material.”

In addition, P22-Hyd both breaks the chemical bonds of water to create hydrogen and also works in reverse to recombine hydrogen and oxygen to generate power. “The reaction runs both ways—it can be used either as a catalyst or as a fuel cell catalyst,” Douglas said.

The form of hydrogenase is one of three occurring in nature: di-iron (FeFe)-, iron-only (Fe-only)- and nickel-iron (NiFe)-hydrogenase. The third form was selected for the new material due to its ability to easily integrate into biomaterials and tolerate exposure to oxygen.

NiFe-hydrogenase also gains significantly greater resistance upon encapsulation to breakdown from chemicals in the environment, and it retains the ability to catalyze at room temperature. Unaltered NiFe-hydrogenase, by contrast, is highly susceptible to destruction from chemicals in the environment and breaks down at temperatures above —both of which make the unprotected enzyme a poor choice for use in manufacturing and commercial products such as cars.

These sensitivities are “some of the key reasons enzymes haven’t previously lived up to their promise in technology,” Douglas said. Another is their difficulty to produce.

“No one’s ever had a way to create a large enough amount of this hydrogenase despite its incredible potential for biofuel production. But now we’ve got a method to stabilize and produce high quantities of the material—and enormous increases in efficiency,” he said.

The development is highly significant according to Seung-Wuk Lee, professor of bioengineering at the University of California-Berkeley, who was not a part of the study.

“Douglas’ group has been leading protein- or virus-based nanomaterial development for the last two decades. This is a new pioneering work to produce green and clean fuels to tackle the real-world energy problem that we face today and make an immediate impact in our life in the near future,” said Lee, whose work has been cited in a U.S. Congressional report on the use of viruses in manufacturing.

Beyond the new study, Douglas and his colleagues continue to craft P22-Hyd into an ideal ingredient for hydrogen power by investigating ways to activate a catalytic reaction with sunlight, as opposed to introducing elections using laboratory methods.

“Incorporating this material into a solar-powered system is the next step,” Douglas said.

Explore further: Temporary storage for electrons: Natural method of producing hydrogen

More information: Paul C. Jordan et al. Self-assembling biomolecular catalysts for hydrogen production, Nature Chemistry (2015). DOI: 10.1038/nchem.2416

 

 

Perovskite New Materials 20 plus id42356EPFL scientists have developed a solar-panel material that can cut down on photovoltaic costs while achieving competitive power-conversion efficiency of 20.2%.
Some of the most promising solar cells today use light-harvesting films made from perovskites – a group of materials that share a characteristic molecular structure. However, perovskite-based solar cells use expensive “hole-transporting” materials, whose function is to move the positive charges that are generated when light hits the perovskite film. Publishing in Nature Energy (“A molecularly engineered hole-transporting material for e cient perovskite solar cells”), EPFL scientists have now engineered a considerably cheaper hole-transporting material that costs only a fifth of existing ones while keeping the efficiency of the solar cell above 20%.
FDT on a Perovskite Surface
This is a 3-D illustration of FDT molecules on a surface of perovskite crystals. (Image: Sven M. Hein / EPFL)
As the quality of perovskite films increases, researchers are seeking other ways of improving the overall performance of solar cells. Inadvertently, this search targets the other key element of a solar panel, the hole-transporting layer, and specifically, the materials that make them up. There are currently only two hole-transporting materials available for perovskite-based solar cells. Both types are quite costly to synthesize, adding to the overall expense of the solar cell.
To address this problem, a team of researchers led by Mohammad Nazeeruddin at EPFL developed a molecularly engineered hole-transporting material, called FDT, that can bring costs down while keeping efficiency up to competitive levels. Tests showed that the efficiency of FDT rose to 20.2% – higher than the other two, more expensive alternatives. And because FDT can be easily modified, it acts as a blueprint for an entire generation of new low-cost hole-transporting materials.
“The best performing perovskite solar cells use hole transporting materials, which are difficult to make and purify, and are prohibitively expensive, costing over €300 per gram preventing market penetration,” says Nazeeruddin. “By comparison, FDT is easy to synthesize and purify, and its cost is estimated to be a fifth of that for existing materials – while matching, and even surpassing their performance.”
Source: Ecole Polytechnique Fédérale de Lausanne
Super Oxide Battery id42324While lithium-ion batteries have transformed our everyday lives, researchers are currently trying to find new chemistries that could offer even better energy possibilities. One of these chemistries, lithium-air, could promise greater energy density but has certain drawbacks as well.
Now, thanks to research at the U.S. Department of Energy’s (DOE’s) Argonne National Laboratory, one of those drawbacks may have been overcome (Nature, “A lithium–oxygen battery based on lithium superoxide”).
text
The lattice match between LiO2 and Ir3Li may be responsible for the LiO2 discharge product found for the Ir-rGO cathode material.
All previous work on lithium-air batteries showed the same phenomenon: the formation of lithium peroxide (Li2O2), a solid precipitate that clogged the pores of the electrode.
In a recent experiment, however, Argonne battery scientists Jun Lu, Larry Curtiss and Khalil Amine, along with American and Korean collaborators, were able to produce stable crystallized lithium superoxide (LiO2) instead of lithium peroxide during battery discharging. Unlike lithium peroxide, lithium superoxide can easily dissociate into lithium and oxygen, leading to high efficiency and good cycle life.
“This discovery really opens a pathway for the potential development of a new kind of battery,” Curtiss said. “Although a lot more research is needed, the cycle life of the battery is what we were looking for.”
The major advantage of a battery based on lithium superoxide, Curtiss and Amine explained, is that it allows, at least in theory, for the creation of a lithium-air battery that consists of what chemists call a “closed system.” Open systems require the consistent intake of extra oxygen from the environment, while closed systems do not — making them safer and more efficient.
“The stabilization of the superoxide phase could lead to developing a new closed battery system based on lithium superoxide, which has the potential of offering truly five times the energy density of lithium ion,” Amine said.
Curtiss and Lu attributed the growth of the lithium superoxide to the spacing of iridium atoms in the electrode used in the experiment. “It looks like iridium will serve as a good template for the growth of superoxide,” Curtiss said.
“However, this is just an intermediate step,” Lu added. “We have to learn how to design catalysts to understand exactly what’s involved in lithium-air batteries.”
Source: Argonne National Laboratory

WEF 2016 wef_1810917bGENEVA—

World Economic Forum founder Klaus Schwab says the fusion of different technological advances, which are changing the world as never before, will be a major focus at the for Fundamental changes ahead

Taking center stage will be an in-depth discussion about what Klaus Schwab, the founder of the World Economic Forum, calls the Fourth Industrial Revolution. Schwab says the revolution is being driven by advances in artificial intelligence, robotics, autonomous vehicles, 3-D printing, nanotechnology and other areas of science.

“This fourth revolution comes on us like a tsunami. The speed is not to be compared with last revolutions and… the speed of this revolution is so fast that it makes it difficult or even impossible for the political community to follow up with the necessary regulatory and legislative frameworks.”

Impact on employment

Schwab says robotics, with new innovations such as self-guided cars, will destroy employment and wipe out much of the middle class, a major pillar of democratic systems.

“My fear is, if we are not prepared…and we have a concentration of jobs in the high level, more innovative areas and in the low service areas, this could lead to a new problem of social exclusion, which we absolutely have to avoid,” he said.

Read the Full Article Here:

“World Unprepared to Deal with Fourth Industrial Revolution”

Do you agree with WEF Founder Klaus Schwab?  OR …

Do you believe that new Technologies, Materials, Abundant Renewable Energy Sources, Access to Clean Water and Advanced Health Care will propel mankind and our ‘Blue Planet’ … into a new era of Human accomplishment?hydrogen-earth-150x150

Please send us your thoughts and comments. We will post the results and some of the best comments we receive.

Read about Genesis Nanotechnology and ‘Our Vision’ here:

Genesis Nanotechnology Vision


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