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  • Scientists use shape-fixing nanoreactor to make a better fuel cell catalyst
    further improve upon the new method in the future such as by finding new polymer precursors that may perform better than polyaniline Explore further Single atom gold catalysts may offer path to low cost production of fuel and chemicals More information Wei Ding et al Shape Fixing via Salt Recrystallization A Morphology Controlled Approach To Convert Nanostructured Polymer to Carbon Nanomaterial as a Highly Active Catalyst for Oxygen Reduction Reaction Journal of the American Chemical Society DOI 10 1021 jacs 5b00292 Journal reference Journal of the American Chemical Society 2081 shares feedback to editors 2015 Phys org Tweet Favorites Email Print PDF Featured Last comments Popular Detection of gravitational waves would open new window on universe Feb 10 2016 58 Gravitational waves detected 100 years after Einstein s prediction Feb 11 2016 144 Physicists create first photonic Maxwell s demon 15 hours ago 3 GPS tracking down to the centimeter Feb 11 2016 10 A metal that behaves like water Feb 11 2016 2 more Phys org on facebook Relevant PhysicsForums posts When is ΔH ΔU 6 hours ago Which group has greater steric hindrance Feb 11 2016 Comparison Calibration Method Feb 11 2016 Which compound will be extracted in organic layer Feb 10 2016 Kinetic vs thermodynamics control Feb 10 2016 Electroplating with mixed metal electrodes Feb 10 2016 More from Chemistry Related Stories Single atom gold catalysts may offer path to low cost production of fuel and chemicals November 27 2014 New catalysts designed and investigated by Tufts University School of Engineering researchers and collaborators from other university and national laboratories have the potential to greatly reduce processing costs in future Kitchen sponge supercapacitor has many porous benefits February 6 2015 By dipping small pieces of an ordinary kitchen sponge into solutions of nanoscale electrode materials scientists have created a light weight low cost supercapacitor that benefits from the sponge s porous structure The Researchers bring clean energy a step closer February 27 2015 For nearly half a century scientists have been trying to replace precious metal catalysts in fuel cells Now for the first time researchers at Case Western Reserve University have shown that an inexpensive metal free catalyst Aerogel catalyst shows promise for fuel cells March 2 2015 Phys org Graphene nanoribbons formed into a three dimensional aerogel and enhanced with boron and nitrogen are excellent catalysts for fuel cells even in comparison to platinum according to Rice University researchers New nanomaterials will boost renewable energy March 9 2015 Global energy consumption is accelerating at an alarming rate There are three main causes rapid economic expansion population growth and increased reliance on energy based appliances across the world Inexpensive efficient bi metallic electrocatalysts may open floodgates for hydrogen fuel March 17 2015 University of Delaware researchers have discovered a cheap and efficient catalyst for converting water to hydrogen fuel known as hydrogen evolution a vital step in making hydrogen a viable and sustainable energy source Recommended for you A new form of frozen water Scientists reveal

    Original URL path: http://phys.org/news/2015-05-scientists-shape-fixing-nanoreactor-fuel-cell.html (2016-02-13)
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  • Na-ion batteries get closer to replacing Li-ion batteries
    into an outdoor ice rink a University of Nebraska Lincoln led research team has predicted a new molecular form of the slippery stuff that even Mother Nature has never borne New experimental test detects signs of Lyme disease near time of infection February 12 2016 When it comes to early diagnosis of Lyme disease the insidious tick borne illness that afflicts about 300 000 Americans annually finding the proverbial needle in the haystack might be a far easier challenge until now Visible blue light induces copper catalyzed C N cross couplings February 12 2016 Phys org A small team of researchers at California Institute of Technology has found a way to use visible blue light to induce copper catalyzed C N cross couplings In their paper published in the journal Science the Mussel mimicking adhesive polymer shown to be non toxic to cells February 12 2016 Purdue University researchers have shown that a synthetic version of a high strength adhesive produced by mussels is non toxic to living cells suggesting its potential suitability for surgical and other biomedical applications Researchers discover new glass technology February 11 2016 Imagine if the picture window in your living room could double as a giant thermostat or big screen TV A discovery by researchers at the University of British Columbia has brought us one step closer to this becoming a reality Cotton candy machines may hold key for making artificial organs February 8 2016 Cotton candy machines may hold the key for making life sized artificial livers kidneys bones and other essential organs 23 comments 2 5 Adjust slider to filter visible comments by rank Display comments newest first tadchem 1 8 5 5 Mar 03 2015 United American Air France and Delta Airlines no longer accept bulk packages of rechargeable lithium batteries for shipment by air due to the risk of fire TheGhostofOtto1923 2 5 5 8 Mar 03 2015 I wonder if Musks 5B Li ion battery factory can accomodate developments like this Peter Mortensen 3 8 5 5 Mar 03 2015 It s great we have so much R D taking place in battery chemistry I disagree that we need to be so concerned about the Lithium resources Even if every car in the world became an EV with the amount of Lithium as in a Model S with currently known resources we would still have plenty more I believe the key to ensure long term sustainability of Lithium based batteries is to ensure that the metal gets maximally recycled Unlike fossil fuels Lithium doesn t burn up inside the batteries But if Na Ion can beat Li Ion then that s only wonderful But always remember that most news from research labs about battery technology have one sole purpose secure additional funding And in the efforts of getting funding for energy related projects you can find a lot of deception out there It s a high stake area of R D and groundbreaking research can get lots of money Telling the positive side and avoiding the negative is common practice holoman 3 7 5 3 Mar 03 2015 Interesting no discussion on discarding batteries re cycling etc I think good technology but concerned with safety and environment antialias physorg 4 2 5 5 Mar 03 2015 But if Na Ion can beat Li Ion then that s only wonderful I don t see it as one beating the other Each will have their uses Even slow charge discharge batteries can be immensely useful if they are dirt cheap e g as stabilizing batteries for the grid and as intermediate energy storage Interesting no discussion on discarding batteries Sodium is environmentally benign But as with all batteries a recycling scheme is certainly a good idea Scottingham 4 7 5 3 Mar 03 2015 The electrodes sound complex and delicate to manufacture The cost would still likely remain quite high even if the raw materials themselves are cheap B Fast 4 3 5 3 Mar 03 2015 and more abundant than lithium A bit of an understatement yes The only thing that frustrates me about this report is that I have read so very many reports of new science revolutionizing batteries but I have seen little real change in the last decade monterino 3 5 2 Mar 03 2015 MIT freshman to news gathering rookie We may may may possibly be able to turn horse manure into a battery that could possibly be 0001 better than other batteries I was at lunch with my prof and some big thinkers when the idea was discussed News gathering rookie Great I think I have my headline Horse poop battery that will kill Li ion just around the corner Bob Wallace 5 5 1 Mar 03 2015 Increased use of lithium means that we could run short on processed lithium if we don t mine and process more lithium Thing is we are opening more lithium mines Tesla Panasonic will be getting the lithium for their gigafactory from a newly opened mine in Nevada At 20 mg lithium per kg of Earth s crust lithium is the 25th most abundant element Nickel and lead have about the same abundance There are approximately 39 million tonnes of accessible lithium in the Earth s crust The Nissan Leaf contains 4 kg of lithium Assume we use 3x as much for each EV in the future 39 million tonnes 3 250 000 000 EVs At some point we start recycling And if we re still using lithium further down the road there are approximately 208 652 550 000 tonnes of lithium in seawater Frosted Flake 3 7 5 3 Mar 04 2015 Oh NOOOOO We are running out of LITHIUM Won t someone please PLEASE kick me in the balls What What does hyperbole mean JoeBlue not rated yet Mar 04 2015 Oh NOOOOO We are running out of LITHIUM Won t someone please PLEASE kick me in the balls What What does hyperbole mean It means you

    Original URL path: http://phys.org/news/2015-03-na-ion-batteries-closer-li-ion.html (2016-02-13)
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  • Red light goes green: Metal-free organic sensitizers portend significant advance in artificial photosynthesis
    system worked under red light wavelengths longer than 590 nm that is so that absorption was occurring only in the Q band region because most of the photon flux in sunlight is in the red and near infrared part of the spectrum Previously he points out only metal containing sensitizers that absorb in the blue at wavelengths shorter than 500 nm had been used in this kind of water splitting cell A significant challenge the Arizona State part of the team faced was to design and synthesize porphyrin molecules that were sufficiently oxidizing to drive the rapid oxidation of water as well as sufficiently reducing in their excited state to rapidly inject an electron into the titanium dioxide conduction band We tuned the oxidizing power of the porphyrins by placing appropriate substituents on the porphyrin ring Mallouk recounts In addition the porphyrins needed to be designed with specific functional groups that would allow attachment to the oxide electrode surface To that end the Penn State part of the team had to determine the right conditions for adsorbing these molecules on the electrode surface which was made easier by their already having worked out the testing conditions and the methods for determining electron transfer rate constants from earlier studies with other dye molecules The Z scheme electron transport chain links the two photosystems found in plants algae and cyanobacteria Credit Wikimedia Commons Licensed under GFDL CC BY SA 3 0 The paper also notes that while the open circuit photovoltages and integrated photocurrents are quite similar for most of the free base porphyrin sensitizers the scientists deeper analysis of the spectral and electrochemical properties of the sensitizers reveals significant differences We found that changing the substituents on the porphyrin ring had a relatively small effect on the energy of the excited state which correlates with the difference between the excited and ground state oxidation potentials Mallouk explains However changing the substituents did significantly shift these potentials relative to the oxygen water potential For example with electron withdrawing substituents the oxidized form of the molecule was a more powerful oxidant but the excited state was a weaker reductant There s a tradeoff between these properties since one would like both electron injection from the excited state and oxidation of water from the oxidized form of the dye to be fast processes and the rates of these processes depend on and are sensitive to the electrochemical driving force for electron transfer In the paper the scientists discuss their ideas on developing a kinetic picture to enable rational design strategies for improving the system Previously they had developed 2 a model for dye sensitized water splitting photoelectrochemical cells that incorporates the kinetics of all the electron transfer reactions in the system These processes Mallouk tells Phys org include electron injection from the excited state molecule into the TiO 2 semiconductor electron transfer from the water oxidation catalyst to the oxidized dye electron transport in the TiO 2 electrode electron hopping between sensitizer molecules and two parasitic recombination processes that is back electron transfer from TiO 2 to the oxidized dye and electron scavenging by the water oxidation catalyst While the recombination processes are winning the battle so the overall quantum yield of water splitting is low we know that all the electron transfer rates depend strongly on the distance between redox partners so we hope to slow down the parasitic reactions using core shell electrode structures a strategy already demonstrated with ruthenium containing sensitizers by our team and by Prof Thomas J Meyer s group at the University of North Carolina at Chapel Hill We re also investigating molecular catalysts in order to shorten the electron hopping pathway from the dye to the catalyst What s critical is that each of these design ideas can be tested by measuring the kinetic rate constants which the scientists obtain from the time dependent photocurrent and photovoltage in the cell A central point made in the paper is that the utilization of red light to drive water splitting represents a significant step forward for molecular photoelectrochemical water splitting systems Yes it s an important step Mallouk explains because red light accounts for most of the energy in the solar spectrum In addition there are other macrocyclic compounds that are structurally related to porphyrins that while being a bit more challenging to synthesize are much stronger red light absorbers We hope to investigate those molecules in the future In addition to developing core shell structures and molecular catalysts as discussed above the scientists are creating sensitizer molecules that should absorb more strongly in the red visible spectrum Moreover the Arizona State team has made linked sensitizer mediator molecules that speed up electron transfer between the catalyst and the sensitizer molecule We re also working on a molecular photocathode assembly that should develop sufficient photovoltage to generate hydrogen without applying a bias voltage to the cell Mallouk adds Together with the photoanode assembly this will make a photoelectrochemical Z scheme in which two photons are absorbed one at the anode the other at the cathode for each electron transferred in the cell The so called Z scheme typically refers to oxidation reduction processes in reactions to light during natural photosynthesis As part of this project Mallouk concludes we and other groups have begun to develop membranes for use in water splitting solar cells 3 4 5 We believe that the membrane results could be broadly applicable to electrolyzers and related technologies for solar fuels including systems that reduce CO 2 to carbon containing fuels Explore further Efficient Catalysts for Making Oxygen for Artificial Photosynthesis More information Metal free organic sensitizers for use in water splitting dye sensitized photoelectrochemical cells Proceedings of the National Academy of Sciences Published online before print January 12 2015 doi 10 1073 pnas 1414901112 Related 1 Limiting and realizable efficiencies of solar photolysis of water Nature 1985 316 495 500 doi 10 1038 316495a0 2 Effects of electron trapping and protonation on the efficiency of

    Original URL path: http://phys.org/news/2015-02-red-green-metal-free-sensitizers-portend.html (2016-02-13)
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  • Materials Science News - Chemistry News(... continued page 2)
    as that of metals are still very scarce Aug 19 2014 in Materials Science feature 1328 0 Four color theorem linked to crystal s magnetic properties Phys org Sometimes mathematical theories have implications that extend far beyond their original purpose This situation holds true for the four color theorem which was originally used by cartographers hundreds of years Jun 09 2014 in Materials Science feature 1025 3 Perovskite solar cells become even more promising with cheaper materials Phys org Due to their rapid improvements in a short amount of time perovskite solar cells have become one of today s most promising up and coming photovoltaic technologies Currently the record efficiency for a perovskite Jan 07 2014 in Materials Science report 0 1 New view of dendrites in Li batteries gets to the root of the problem Phys org One of the biggest challenges facing rechargeable batteries with lithium Li electrodes is the growth of dendrites which can short circuit the batteries and cause complete failure Although dendrites do their Dec 09 2013 in Materials Science feature 1 1 Peanut particles could be used to build micro scale factories Phys org One of the main components of a factory is the robots that transport and assemble objects of varying shapes and sizes When scaling down to the micro level the steel and wiring that these robots are made of Nov 08 2013 in Materials Science feature 0 1 Chemical passwords could lead to unbreakable molecular lock Phys org If you re in the business of cracking codes it would be pretty difficult to break into a security system that you don t even know is there That s one of the advantages of molecular keypad locks whose small Oct 22 2013 in Materials Science feature 0 1 Delicate oxidation can transform

    Original URL path: http://phys.org/chemistry-news/materials-science/sort/rank/all/page2.html (2016-02-13)
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  • Materials Science News - Chemistry News(... continued page 3)
    second largest is the more often overlooked cement industry which accounts for 5 6 of all anthropogenic CO2 Apr 10 2012 in Materials Science report 0 22 Rational design can improve hydrogen fuel cell efficiency PhysOrg com Hydrogen fuel cells in which the chemical energy of hydrogen is converted into electricity offer the potential for a wide variety of applications especially in transportation and power generation Although Feb 29 2012 in Materials Science feature 0 0 Millions of molecules screened in search for the ideal organic solar cell material PhysOrg com Currently the cost of electricity from commercial silicon solar cells is about 10 times higher than the cost of utility scale electricity In order to make solar cells cost competitive with currently available Sep 12 2011 in Materials Science feature 0 12 Artificial light harvesting method achieves 100 energy transfer efficiency PhysOrg com In an attempt to mimic the photosynthetic systems found in plants and some bacteria scientists have taken a step toward developing an artificial light harvesting system LHS that meets one of the crucial Sep 01 2011 in Materials Science feature 0 22 Cheap abundant cathode material found for producing hydrogen fuel w video PhysOrg com By replacing catalysts made of expensive noble metals like platinum with cheaper earth abundant materials researchers have taken a step toward enabling the large scale production of hydrogen from sunlight May 10 2011 in Materials Science feature 0 60 Chemists fabricate impossible material PhysOrg com When atoms combine to form compounds they must follow certain bonding and valence rules For this reason many compounds simply cannot exist But there are some compounds that although they follow the bonding Apr 25 2011 in Materials Science feature 0 9 Lithium ion battery with new chemistry could power electric vehicles PhysOrg com While car

    Original URL path: http://phys.org/chemistry-news/materials-science/sort/rank/all/page3.html (2016-02-13)
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  • Materials Science News - Chemistry News(... continued page 4)
    used to increase the efficiency of an inexpensive type of solar cell In Oct 30 2009 in Materials Science feature 0 1 Scientists Make Ink Disappear Make Paper Reusable PhysOrg com Despite ongoing efforts to save the trees many offices print high volumes of paper documents on a daily basis Although many companies encourage paper recycling both disposing of and recycling paper have Oct 27 2009 in Materials Science feature 0 4 A new form of frozen water Scientists reveal new ice with record low density Amid the season known for transforming Nebraska into an outdoor ice rink a University of Nebraska Lincoln led research team has predicted a new molecular form of the slippery stuff that even Mother Nature has never borne 5 hours ago in Materials Science 1421 0 Synthetic strategy for enantioselective aldol reactions with fluoroacetate Phys org Fluorine the most electronegative atom on the periodic table has some interesting applications in organic and medicinal chemistry Replacing hydrogen with fluorine can often boost biological activity and carbon fluorine Jan 27 2016 in Materials Science report 718 1 Team devises easier way to make bijels a complex new form of liquid matter Oil and water famously don t mix but finely dispersing one in the other produces a liquid mixture with many useful properties An emulsion consisting of tiny droplets of one of those liquids immersed in the other is the Jan 27 2016 in Materials Science 806 0 First materials to be woven at the atomic and molecular levels created There are many different ways to make nanomaterials 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 Jan 21 2016 in Materials Science 4788 3 New

    Original URL path: http://phys.org/chemistry-news/materials-science/sort/rank/all/page4.html (2016-02-13)
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  • Materials Science News - Chemistry News(... continued page 5)
    inside the body and diagnose ailments but they needed a certain type of molecule to improve the imaging depth They invented a long wavelength near infrared fluorescent molecule and it works Dec 24 2015 in Materials Science 1210 0 Exceptionally strong and lightweight new metal created A team led by researchers from the UCLA Henry Samueli School of Engineering and Applied Science has created a super strong yet light structural metal with extremely high specific strength and modulus or stiffness to weight Dec 23 2015 in Materials Science 7205 18 Toward liquid fuels from carbon dioxide In the quest for sustainable alternative energy and fuel sources one viable solution may be the conversion of the greenhouse gas carbon dioxide CO2 into liquid fuels Dec 23 2015 in Materials Science 1474 13 Study clarifies the role of the leaving group in gas phase bimolecular reaction One of the first reaction mechanisms students learn in undergraduate organic chemistry is the SN2 reaction Named because it involves the collision of two molecules its energy barrier is related to the nucleophile the solvent Dec 18 2015 in Materials Science weblog 793 0 New hydrogel gives clues to mechanism behind stress stiffening mediated mesenchymal stem cell fate Phys org Several properties of the extracellular matrix affect cellular interaction including stem cell differentiation Some of these are physical properties such as topography and matrix stiffness In an effort to Dec 17 2015 in Materials Science report 508 0 Transparent metal films for smart phone tablet and TV displays A new material that is both highly transparent and electrically conductive could make large screen displays smart windows and even touch screens and solar cells more affordable and efficient according to the Penn State Dec 15 2015 in Materials Science 4223 3 Chemical state thought to be unobservable

    Original URL path: http://phys.org/chemistry-news/materials-science/sort/rank/all/page5.html (2016-02-13)
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  • Materials Science News - Chemistry News(... continued page 7)
    and oxygen and then harvest Oct 30 2015 in Materials Science 5750 5 Team hacks off the shelf 3 D printer towards rebuilding the heart As of this month over 4 000 Americans are on the waiting list to receive a heart transplant With failing hearts these patients have no other options heart tissue unlike other parts of the body is unable to heal itself Oct 23 2015 in Materials Science 1613 1 Cobalt ligand catalyst successfully converts carboxylic acids and esters into alcohols Phys org Researchers report the discovery of a cobalt ligand catalyst system that serves as a homogeneous catalyst for the hydrogenation of esters and carboxylic acids to alcohols Ties J Korstanje Jarl Ivar van der Oct 23 2015 in Materials Science report 2213 1 Super slick material makes steel better stronger cleaner Steel is ubiquitous in our daily lives We cook in stainless steel skillets ride steel subway cars over steel rails to our offices in steel framed building Steel screws hold together broken bones steel braces straighten Oct 20 2015 in Materials Science 894 6 Covalent organic framework that has highest reported stability and can be modified for organocatalysis Phys org A group of researchers from the Institute for Molecular Science National Institutes of Natural Sciences in Japan report a novel covalent organic framework COF that is crystalline highly stable in water strong Oct 06 2015 in Materials Science report 1324 0 Researchers print inside gels to create unique shapes Phys org A team of researchers at the University of Florida has taken the technique of printing objects inside of a gel a step further by using a highly shear rate sensitive gel In their paper published in the journal Sep 30 2015 in Materials Science report 619 0 Discovery of a highly efficient catalyst

    Original URL path: http://phys.org/chemistry-news/materials-science/sort/rank/all/page7.html (2016-02-13)
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