Hydrogen technologies and fuel cells offer an alternative and improved solution for a decarbonised energy future.Fuel cells are electrochemical converters;transforming hydrogen (or energy sources containing hydrogen) ...Hydrogen technologies and fuel cells offer an alternative and improved solution for a decarbonised energy future.Fuel cells are electrochemical converters;transforming hydrogen (or energy sources containing hydrogen) and oxygen directly into electricity.The hydrogen fuel cell,invented in 1839,permits the generation of electrical energy with high efficiency through a non-combustion,electrochemical process and,importantly,without the emission ofits point of use.Hitherto,despite numerous efforts to exploit the obvious attractions of hydrogen technologies and hydrogen fuel cells,various challenges have been encountered,some of which are reviewed here.Now,however,given the exigent need to urgently seek low-carbon paths for humankind’s energy future,numerous countries are advancing the deployment of hydrogen technologies and hydrogen fuel cells not only for transport,but also as a means of the storage of excess renewable energy from,for example,wind and solar farms.Furthermore,hydrogen is also being blended into the natural gas supplies used in domestic heating and targeted in the decarbonisation of critical,large-scale industrial processes such as steel making.We briefly review specific examples in countries such as Japan,South Korea and the People’s Republic of China,as well as selected examples from Europe and North America in the utilization of hydrogen technologies and hydrogen fuel cells.展开更多
Sulfur and lanthanum hydrides under compression display superconducting states with high observed critical temperatures.It has been recently demonstrated that carbonaceous sulfur hydride displays room temperature supe...Sulfur and lanthanum hydrides under compression display superconducting states with high observed critical temperatures.It has been recently demonstrated that carbonaceous sulfur hydride displays room temperature superconductivity.However,this phenomenon has been observed only at very high pressure.Here,we theoretically search for superconductors with very high critical temperatures,but at much lower pressures.We describe two of such sodalite-type clathrate hydrides,YbH6 and LuH6.These hydrides are metastable and are predicted to superconduct with T_(c)~145 K at 70 GPa and T_(c)~273 K at 100 GPa,respectively.This striking result is a consequence of the strong interrelationship between the f states present at the Fermi level,structural stability,and the final T_(c) value.For example,TmH6,with unfilled 4f orbitals,is stable at 50 GPa,but has a relatively low value of T_(c) of 25 K.The YbH6 and LuH6 compounds,with their filled f-shells,exhibit prominent phonon"softening",which leads to a strong electron-phonon coupling,and as a result,an increase in T_(c).展开更多
Helium is the second most abundant element in the universe, and together with silica, they are important components of giant planets. Exploring the reactivity and state of helium and silica under high pressure is cruc...Helium is the second most abundant element in the universe, and together with silica, they are important components of giant planets. Exploring the reactivity and state of helium and silica under high pressure is crucial for understanding of the evolution and internal structure of giant planets. Here, using first-principles calculations and crystal structure predictions, we identify four stable phases of a helium-silica compound with seven/eight-coordinated silicon atoms at pressure of 600–4000 GPa, corresponding to the interior condition of the outer planets in the solar system. The density of He Si O2 agrees with current structure models of the planets.This helium-silica compound exhibits a superionic-like helium diffusive state under the high-pressure and hightemperature conditions along the isentropes of Saturn, a metallic fluid state in Jupiter, and a solid state in the deep interiors of Uranus and Neptune. These results show that helium may affect the erosion of the rocky core in giant planets and may help to form a diluted core region, which not only highlight the reactivity of helium under high pressure but also provide evidence helpful for building more sophisticated interior models of giant planets.展开更多
基金Professor Sir John Meurig Thomas FRS FREng,Department of Materials Science and Metallurgy,University of Cambridge.He is one of the founders of solid-state chemistry and the surface and materials chemistry of solids.He was one of the first chemists in the world to use electron microscopy as a chemical tool,which he initiated in the University of Wales(Bangor)in 1964.He has made numerous studies in heterogeneous catalysis and made significant contributions to the study of minerals,especially silicates,zeolites and clays as well as graphite and diamond.For his contributions to geochemistry,a new mineral,Meurigite,was named in his honour.He was once head of Physical Chemistry in the University of Cambridge and Director of the Royal Institution of Great BritainCorresponding author::Peter P.Edwards FRS ML holds the Statutory Chair of Inorganic Chemistry at Oxford and is the Co-Director of the KACST-Oxford Centre of Excellence in Petrochemicals,also at Oxford.He has previously held positions at Birmingham(Professor of Chemistry and of Materials),Cambridge(Lecturer in Chemistry and Director of Studies in Chemistry,Jesus College)and Cornell(British Fulbright Scholar and National Science Foundation Fellow).He was Co-Founder of the firstever UK Interdisciplinary Research Centre,that in Superconductivity at Cambridge and the UK Sustainable Hydrogen Energy Consortium(UKSHEC).He has been Chair of the European Research Council Advanced Investigators Award Panel on Chemical Synthesis and Advanced Materials.Edwards is Fellow of the Royal Society+1 种基金Einstein Professor of the Chinese Academy of SciencesMember,German Academy of Sciences,International Honorary Member of the US Academy of Arts and Sciences,International Member of the American Philosophical Society,and Member of the Academia Europaea.His current major interests include:Targeted reconstruction of plastic waste to hydrogen and starting monomers,converting carbon dioxide to carbon-neutral fuels and Green hydrogen from fossil hydrocarbon fuels,E-mail address:peter.edwards@chem.ox.ac.uk。
文摘Hydrogen technologies and fuel cells offer an alternative and improved solution for a decarbonised energy future.Fuel cells are electrochemical converters;transforming hydrogen (or energy sources containing hydrogen) and oxygen directly into electricity.The hydrogen fuel cell,invented in 1839,permits the generation of electrical energy with high efficiency through a non-combustion,electrochemical process and,importantly,without the emission ofits point of use.Hitherto,despite numerous efforts to exploit the obvious attractions of hydrogen technologies and hydrogen fuel cells,various challenges have been encountered,some of which are reviewed here.Now,however,given the exigent need to urgently seek low-carbon paths for humankind’s energy future,numerous countries are advancing the deployment of hydrogen technologies and hydrogen fuel cells not only for transport,but also as a means of the storage of excess renewable energy from,for example,wind and solar farms.Furthermore,hydrogen is also being blended into the natural gas supplies used in domestic heating and targeted in the decarbonisation of critical,large-scale industrial processes such as steel making.We briefly review specific examples in countries such as Japan,South Korea and the People’s Republic of China,as well as selected examples from Europe and North America in the utilization of hydrogen technologies and hydrogen fuel cells.
基金Supported by the National Natural Science Foundation of China(Grant Nos.12122405,51632002,and 11974133)the Program for Changjiang Scholars and Innovative Research Team in Universities(Grant No.IRT 15R23)+1 种基金financial support from the Engineering and Physical Sciences Research Council(Grant No.EP/P022596/1)。
文摘Sulfur and lanthanum hydrides under compression display superconducting states with high observed critical temperatures.It has been recently demonstrated that carbonaceous sulfur hydride displays room temperature superconductivity.However,this phenomenon has been observed only at very high pressure.Here,we theoretically search for superconductors with very high critical temperatures,but at much lower pressures.We describe two of such sodalite-type clathrate hydrides,YbH6 and LuH6.These hydrides are metastable and are predicted to superconduct with T_(c)~145 K at 70 GPa and T_(c)~273 K at 100 GPa,respectively.This striking result is a consequence of the strong interrelationship between the f states present at the Fermi level,structural stability,and the final T_(c) value.For example,TmH6,with unfilled 4f orbitals,is stable at 50 GPa,but has a relatively low value of T_(c) of 25 K.The YbH6 and LuH6 compounds,with their filled f-shells,exhibit prominent phonon"softening",which leads to a strong electron-phonon coupling,and as a result,an increase in T_(c).
基金the financial support from the National Natural Science Foundation of China (Grant Nos. 12125404, 11974162, and 11834006)the Fundamental Research Funds for the Central Universities。
文摘Helium is the second most abundant element in the universe, and together with silica, they are important components of giant planets. Exploring the reactivity and state of helium and silica under high pressure is crucial for understanding of the evolution and internal structure of giant planets. Here, using first-principles calculations and crystal structure predictions, we identify four stable phases of a helium-silica compound with seven/eight-coordinated silicon atoms at pressure of 600–4000 GPa, corresponding to the interior condition of the outer planets in the solar system. The density of He Si O2 agrees with current structure models of the planets.This helium-silica compound exhibits a superionic-like helium diffusive state under the high-pressure and hightemperature conditions along the isentropes of Saturn, a metallic fluid state in Jupiter, and a solid state in the deep interiors of Uranus and Neptune. These results show that helium may affect the erosion of the rocky core in giant planets and may help to form a diluted core region, which not only highlight the reactivity of helium under high pressure but also provide evidence helpful for building more sophisticated interior models of giant planets.
