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Light-driven bioethanol dehydration offers attractive outlooks for the sustainable production of ethylene. Herein, a surface-hydrogenated CrMnO x is coupled with GaN nanowires (GaN@CMO-H) for light-driven ethanol dehydration to ethylene. Through combined experimental and computational investigations, a surface hydrogen-replenishment mechanism is proposed to disclose the ethanol dehydration pathway over GaN@CMO-H. Moreover, the surface-hydrogenated GaN@CMO-H can significantly lower the reaction energy barrier of the C 2 H 5 OH-to-C 2 H 4 conversion by switching the rate-determining reaction step compared to both GaN and GaN@CMO. Consequently, the surface-hydrogenated GaN@CMO-H illustrates a considerable ethylene production activity of 1.78 mol·g cat -1 ·h -1 with a high turnover number of 94,769 mole ethylene per mole CrMnO x . This work illustrates a new route for sustainable ethylene production with the only use of bioethanol and sunlight beyond fossil fuels., Competing Interests: Competing interests: The authors declare no competing interests, (© 2025. The Author(s).)

Solar-powered lignin reforming offers a carbon-neutral route for syngas production. This study explores a dual non-precious iron-manganese cocatalyst to simultaneously activate both C-C and C-O bonds for maximizing the utilization of various substituents of native lignin to yield syngas. The cocatalyst, integrated with InGaN nanowires on a Si wafer, affords a measurable syngas evolution rate of 42.4 mol g cat -1  h -1 from native lignin in distilled water with a high selectivity of 93 % and tunable H 2 /CO ratios under concentrated light, leading to a considerable light-to-fuel efficiency of 11.8 %. The high FeMn atom efficiency arising from the 1-dimensional nanostructure of InGaN enables the achievement of a high turnover frequency (TOF) of 220896 mol syngas per mol FeMn per hour. Combined experimental and theoretical investigations reveal that the synergetic iron-manganese cocatalyst supported by InGaN nanowires enables simultaneous activation of C-C and C-O bonds with comparable minimized dissociation energies, thus promising to maximally utilize different substituents of -OCH 3 , and -CH 2 CH 2 CH 3 in lignin for syngas production. Moreover, the dual Fe-Mn cocatalyst demonstrates a most energetically favorable route for the consecutive release of hydrogen from •CH 3 and •OH by the oxidative holes while inhibiting the reversion of hydrogen and hydroxyl into water., (© 2024 Wiley-VCH GmbH.)

The exploration of a new conceptual strategy for improving the oxygen evolution reaction (OER) of earth-abundant electrocatalysts is critical. In this study, chiral copper oxide nanoflower is explored by a self-assembly method. The characterization suggests the chiral structure originates from the crystal plane-level helical stack of the secondary nanosheets. Of note, the assembly illustrates a record-high degree of spin polarization of 96%, indicating the ideal alignment of electron spin. Moreover, density function theory calculations show the chiral structure reducing the reaction energy barrier (REB) while switching the potential-determining step from *O→*OOH to *OH→*O. Together with the enhanced electrochemical active surface area and accelerated charge transfer, the production of ground-state triplet O 2 is improved via a spin-forbidden route that involves the singlet H 2 O/OH•. Consequently, the chiral nanoflower shows a overpotential of 308 mV at 10 mA cm -2 and a Tafel slope of 93.5 mV dec -1 , which is even superior to the commercial RuO 2 (310 mV, 101 mV dec -1 ). This study presents a new strategy for improving the OER activity by simultaneously enhancing electronic properties and lowering the REB of an non-noble electrocatalyst via chirality engineering., (© 2024 Wiley‐VCH GmbH.)

Solar-driven overall conversion of CO 2 and H 2 O into fuels and chemicals shows an ultimate strategy for carbon neutrality yet remains a huge challenge. Herein, an integrated photocatalytic redox architecture of Zn NPs/GaN Nanowires (NWs)/Si is explored for light-driven overall conversion of CO 2 and H 2 O into CH 4 and H 2 O 2 simultaneously without any external sacrificial agents and additives. The as-designed architecture affords a benchmark CH 4 activity of 189 mmol g cat -1  h -1 with a high selectivity of 93.6%, in the synchronized formation of H 2 O 2 at a considerable rate of 25 m g -1  h -1 . Moreover, a considerable turnover number of 27,280 mol CH 4 per mol Zn was achieved over a long-term operation of 80 h. By operando spectroscopic characterizations, isotope experiments, and density functional theory calculations, it is unraveled that Zn sites are synergetic with GaN to drive CO 2 -to-CH 4 conversion with a lowered energy barrier of 0.27 eV while inhibiting hydrogen evolution reaction with a relatively high energy barrier of 0.93 eV. Notably, owing to the unique surface properties of GaN, water is split into *OH and *H, followed by the formation of H 2 O 2 because of the alleviated adsorption strength of *OH by Zn NPs. Together, the hierarchical architecture enables the achievement of high activity and high selectivity of CH 4 from CO 2 reduction in distilled water along with the generation of H 2 O 2 . This work provides an integrated photocatalytic redox architecture for the synchronized production of CH 4 and H 2 O 2 with the only inputs of CO 2 , distilled water, and light., (Copyright © 2024 Science China Press. All rights reserved.)

Transformation of lignin to syngas can turn waste into treasure yet remains a tremendous challenge because of its naturally evolved stubborn structure. In this work, light-driven reforming of natural lignin in water for green syngas production is explored using Pt-decorated InGaN nanowires. The spectroscopic characterizations, isotope, and model compound experiments, as well as density function theory calculation, disclose that among a variety of groups including aromatic ring, -OH, -OCH 3 , -C 3 H 7 with complex chemical bonds of O-H, C-H, C-C, C-O, etc., InGaN nanowires are cooperative with Pt for preferably breaking the C-O bond of the rich O-CH 3 group in lignin to liberating ⋅CH 3 by photogenerated holes with a minimum dissociation energy of 2.33 eV. Syngas are subsequently yielded from the continuous evolution of ⋅CH 3 and ⋅OH from photocatalytic reforming of lignin in water. Together with the superior optoelectronic attributes of Pt-decorated InGaN nanowires, the evolution rate of syngas approaches 43.4 mol ⋅ g -1  ⋅ h -1 with tunable H 2 /CO ratios and a remarkable turnover number (TON) of 150, 543 mol syngas per mol Pt. Notably, the architecture demonstrates a high light efficiency of 12.1 % for syngas generation under focused light without any extra thermal input. Outdoor test ascertains the viability of producing syngas with the only inputs of natural lignin, water, and sunlight, thus presenting a low-carbon route for synthesizing transportation fuels and value-added chemicals., (© 2024 Wiley-VCH GmbH.)

Photo-thermal-coupling ammonia decomposition presents a promising strategy for utilizing the full-spectrum to address the H 2 storage and transportation issues. Herein, we exhibit a photo-thermal-catalytic architecture by assembling gallium nitride nanowires-supported ruthenium nanoparticles on a silicon for extracting hydrogen from ammonia aqueous solution in a batch reactor with only sunlight input. The photoexcited charge carriers make a predomination contribution on H 2 activity with the assistance of the photothermal effect. Upon concentrated light illumination, the architecture significantly reduces the activation energy barrier from 1.08 to 0.22 eV. As a result, a high turnover number of 3,400,750 is reported during 400 h of continuous light illumination, and the H 2 activity per hour  is nearly 1000 times higher than that under the pure thermo-catalytic conditions. The reaction mechanism is extensively studied by coordinating experiments, spectroscopic characterizations, and density functional theory calculation. Outdoor tests validate the viability of such a multifunctional architecture for ammonia decomposition toward H 2 under natural sunlight., (© 2024. The Author(s).)

Hydrogen (H 2 ) has emerged as a clean and versatile energy carrier to power a carbon-neutral economy for the post-fossil era. Hydrogen generation from low-cost and renewable biomass by virtually inexhaustible solar energy presents an innovative strategy to process organic solid waste, combat the energy crisis, and achieve carbon neutrality. Herein, the progress and breakthroughs in solar-powered H 2 production from biomass are reviewed. The basic principles of solar-driven H 2 generation from biomass are first introduced for a better understanding of the reaction mechanism. Next, the merits and shortcomings of various semiconductors and cocatalysts are summarized, and the strategies for addressing the related issues are also elaborated. Then, various bio-based feedstocks for solar-driven H 2 production are reviewed with an emphasis on the effect of photocatalysts and catalytic systems on performance. Of note, the concurrent generation of value-added chemicals from biomass reforming is emphasized as well. Meanwhile, the emerging photo-thermal coupling strategy that shows a grand prospect for maximally utilizing the entire solar energy spectrum is also discussed. Further, the direct utilization of hydrogen from biomass as a green reductant for producing value-added chemicals via organic reactions is also highlighted. Finally, the challenges and perspectives of photoreforming biomass toward hydrogen are envisioned., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

On-site hydrogen production from liquid organic hydrogen carriers e.g., methanol provides an emerging strategy for the safe storage and transportation of hydrogen. Herein, a catalytic architecture consisting of nickel-cobalt nanoclusters dispersed on gallium nitride nanowires supported by silicon for light-driven hydrogen production from methanol is reported. By correlative microscopic, spectroscopic characterizations, and density functional theory calculations, it is revealed that NiCo nanoclusters work in synergy with GaN nanowires to enable the achievement of a significantly reduced activation energy of methanol dehydrogenation by switching the potential-limiting step from *CHO → *CO to *CH 3 O → *CH 2 O. In combination with the marked photothermal effect, a high hydrogen rate of 5.62 mol·gcat-1·h-1 with a prominent turnover frequency of 43,460 h-1 is achieved at 5 Wcm-2 without additional energy input. Remarkably, the synergy between Co and Ni, in combination with the unique surface of GaN, renders the architecture with outstanding resistance to sintering and coking. The architecture thereby exhibits a high turnover number of >16,310,000 over 600 h. Outdoor testing validates the viability of the architecture for active and robust hydrogen evolution under natural concentrated sunlight. Overall, this work presents a promising architecture for on-site hydrogen production from CH 3 OH by virtually unlimited solar energy., (© 2024 Wiley‐VCH GmbH.)

Light-driven dry reforming of methane toward syngas presents a proper solution for alleviating climate change and for the sustainable supply of transportation fuels and chemicals. Herein, Rh/InGaN 1- x O x nanowires supported by silicon wafer are explored as an ideal platform for loading Rh nanoparticles, thus assembling a new nanoarchitecture for this grand topic. In combination with the remarkable photo-thermal synergy, the O atoms in Rh/InGaN 1- x O x can significantly lower the apparent activation energy of dry reforming of methane from 2.96 eV downward to 1.70 eV. The as-designed Rh/InGaN 1- x O x NWs nanoarchitecture thus demonstrates a measurable syngas evolution rate of 180.9 mmol g cat -1 h -1 with a marked selectivity of 96.3% under concentrated light illumination of 6 W cm -2 . What is more, a high turnover number (TON) of 4182 mol syngas per mole Rh has been realized after six reuse cycles without obvious activity degradation. The correlative 18 O isotope labeling experiments, in-situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) and in-situ diffuse reflectance Fourier transform infrared spectroscopy characterizations, as well as density functional theory calculations reveal that under light illumination, Rh/InGaN 1- x O x NWs facilitate releasing *CH 3 and H + from CH 4 by holes, followed by H 2 evolution from H + reduction with electrons. Subsequently, the O atoms in Rh/InGaN 1- x O x can directly participate in CO generation by reacting with the *C species from CH 4 dehydrogenation and contributes to the coke elimination, in concurrent formation of O vacancies. The resultant O vacancies are then replenished by CO 2 , showing an ideal chemical loop. This work presents a green strategy for syngas production via light-driven dry reforming of methane., (Copyright © 2024 Science China Press. Published by Elsevier B.V. All rights reserved.)

Photo-thermal-synergistic hydrogenation is a promising strategy for upcycling carbon dioxide into fuels and chemicals by maximally utilizing full-spectrum solar energy. Herein, by immobilizing Pt-Rh bimetal onto a well-developed GaN NWs/Si platform, CO 2 was photo-thermo-catalytically hydrogenated towards CO under concentrated light illumination without extra energies. The as-designed architecture demonstrates a considerable CO evolution rate of 11.7 mol g GaN -1 h -1 with a high selectivity of 98.5% under concentrated light illumination of 5.3 W cm -2 , leading to a benchmark turnover frequency of 26 486 mol CO per mol PtRh per hour. It is nearly 2-3 orders of magnitude higher than that of pure thermal catalysis under the same temperature by external heating without light. Control experiments, various spectroscopic characterization methods, and density functional theory calculations are correlatively conducted to reveal the origin of the remarkable performance as well as the photo-thermal enhanced mechanism. It is found that the recombination of photogenerated electron-hole pairs is dramatically inhibited under high temperatures arising from the photothermal effect. More critically, the synergy between photogenerated carriers arising from ultraviolet light and photoinduced heat arising from visible- and infrared light enables a sharp reduction of the apparent activation barrier of CO 2 hydrogenation from 2.09 downward to 1.18 eV. The evolution pathway of CO 2 hydrogenation towards CO is also disclosed at the molecular level. Furthermore, compared to monometallic Pt, the introduction of Rh further reduces the desorption energy barrier of *CO by optimizing the electronic properties of Pt, thus enabling the achievement of excellent activity and selectivity. This work provides new insights into CO 2 hydrogenation by maximally utilizing full-spectrum sunlight via photo-thermal synergy., Competing Interests: The authors state that there are no competing interests., (This journal is © The Royal Society of Chemistry.)

Light-driven hydrogen production from biomass derivatives offers a path towards carbon neutrality. It is often however operated with the limitations of sluggish kinetics and severe coking. Herein, a disruptive air-promoted strategy is explored for efficient and durable light-driven hydrogen production from ethanol over a core/shell Cr 2 O 3 @GaN nanoarchitecture. The correlative computational and experimental investigations show ethanol is energetically favorable to be adsorbed on the Cr 2 O 3 @GaN interface, followed by dehydrogenation toward acetaldehyde and protons by photoexcited holes. The released protons are then consumed for H 2 evolution by photogenerated electrons. Afterward, O 2 can be evolved into active oxygen species and promote the deprotonation and C-C cleavage of the key C 2 intermediate, thus significantly lowering the reaction energy barrier of hydrogen evolution and removing the carbon residual with inhibited overoxidation. Consequently, hydrogen is produced at a high rate of 76.9 mole H 2 per gram Cr 2 O 3 @GaN per hour by only feeding ethanol, air, and light, leading to the achievement of a turnover number of 266,943,000 mole H 2 per mole Cr 2 O 3 over a long-term operation of 180 hours. Notably, an unprecedented light-to-hydrogen efficiency of 17.6 % is achieved under concentrated light illumination. The simultaneous generation of aldehyde from ethanol dehydrogenation enables the process more economically promising., (© 2024 Wiley‐VCH GmbH.)

Acute myeloid leukemia (AML) with internal tandem duplication (ITD) mutations in the FLT3 tyrosine kinase tend to have a poor prognosis. FLT3-ITD can promote the progress of AML by activating the PI3K/AKT/mTOR pathway. Paclitaxel (PTX) is a natural anticancer drug that has been widely used in chemotherapy for multiple malignancies. The present study used the CCK-8 assay, flow cytometry, PCR and western blotting to explore the anti-leukemia effect and possible mechanisms of PTX on MV4-11 cells with the FLT3-ITD mutation and the underlying mechanism. As a result, it was found that PTX could inhibit proliferation of MV4-11 cells and promoted apoptosis by inhibiting the PI3K/AKT/mTOR pathway., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 Su et al.)

Upcycling of CO 2 into fuels by virtually unlimited solar energy provides an ultimate solution for addressing the substantial challenges of energy crisis and climate change. In this work, we report an efficient nanostructured Ru/MnO x catalyst composed of well-defined Ru/MnO/Mn 3 O 4 for photo-thermal catalytic CO 2 hydrogenation to CH 4 , which is the result of a combination of external heating and irradiation. Remarkably, under relatively mild conditions of 200 °C, a considerable CH 4 production rate of 166.7 mmol g -1 h -1 was achieved with a superior selectivity of 99.5% at CO 2 conversion of 66.8%. The correlative spectroscopic and theoretical investigations suggest that the yield of CH 4 is enhanced by coordinating photon energy with thermal energy to reduce the activation energy of reaction and promote formation of key intermediate COOH* species over the catalyst. This work opens up a new strategy for CO 2 hydrogenation toward CH 4 ., (© 2024. The Author(s).)

Prior to the eventual arrival of carbon neutrality, solar-driven syngas production from methane steam reforming presents a promising approach to produce transportation fuels and chemicals. Simultaneous activation of the two reactants, i.e. methane and water, with notable geometric and polar discrepancy is at the crux of this important subject yet greatly challenging. This work explores an exceptional semiconducting hybrid of RhO x /GaN@InGaN nanowires for overcoming this critical challenge to achieve efficient syngas generation from methane steam reforming by photocatalysis. By coordinating density functional theoretical calculations and microscopic characterizations, with in situ spectroscopic measurements, it is found that the multifunctional RhO x /GaN interface is effective for simultaneously activating both CH 4 and H 2 O by stretching the C-H and O-H bonds because of its unique Lewis acid/base attribute. With the aid of energetic charge carriers, the stretched C-H and O-H bonds of reactants are favorably cleaved, resulting in the key intermediates, i.e. *CH 3 , *OH, and *H, to sit on Rh sites, Rh sites, and N sites, respectively. Syngas is subsequently produced via energetically favored pathway without additional energy inputs except for light. As a result, a benchmarking syngas formation rate of 8.1 mol·g cat -1 ·h -1 is achieved with varied H 2 /CO ratios from 2.4 to 0.8 under concentrated light illumination of 6.3 W·cm -2 , enabling the achievement of a superior turnover number of 10,493 mol syngas per mol Rh species over 300 min of long-term operation. This work presents a promising strategy for green syngas production from methane steam reforming by utilizing unlimited solar energy., (© The Author(s) 2023. Published by Oxford University Press on behalf of National Academy of Sciences.)

Solar photoelectrochemical reactions have been considered one of the most promising paths for sustainable energy production. To date, however, there has been no demonstration of semiconductor photoelectrodes with long-term stable operation in a two-electrode configuration, which is required for any practical application. Herein, we demonstrate the stable operation of a photocathode comprising Si and GaN, the two most produced semiconductors in the world, for 3,000 hrs without any performance degradation in two-electrode configurations. Measurements in both three- and two-electrode configurations suggest that surfaces of the GaN nanowires on Si photocathode transform in situ into Ga-O-N that drastically enhances hydrogen evolution and remains stable for 3,000 hrs. First principles calculations further revealed that the in-situ Ga-O-N species exhibit atomic-scale surface metallization. This study overcomes the conventional dilemma between efficiency and stability imposed by extrinsic cocatalysts, offering a path for practical application of photoelectrochemical devices and systems for clean energy., (© 2023. The Author(s).)

Production of hydrogen fuel from sunlight and water, two of the most abundant natural resources on Earth, offers one of the most promising pathways for carbon neutrality 1-3 . Some solar hydrogen production approaches, for example, photoelectrochemical water splitting, often require corrosive electrolyte, limiting their performance stability and environmental sustainability 1,3 . Alternatively, clean hydrogen can be produced directly from sunlight and water by photocatalytic water splitting 2,4,5 . The solar-to-hydrogen (STH) efficiency of photocatalytic water splitting, however, has remained very low. Here we have developed a strategy to achieve a high STH efficiency of 9.2 per cent using pure water, concentrated solar light and an indium gallium nitride photocatalyst. The success of this strategy originates from the synergistic effects of promoting forward hydrogen-oxygen evolution and inhibiting the reverse hydrogen-oxygen recombination by operating at an optimal reaction temperature (about 70 degrees Celsius), which can be directly achieved by harvesting the previously wasted infrared light in sunlight. Moreover, this temperature-dependent strategy also leads to an STH efficiency of about 7 per cent from widely available tap water and sea water and an STH efficiency of 6.2 per cent in a large-scale photocatalytic water-splitting system with a natural solar light capacity of 257 watts. Our study offers a practical approach to produce hydrogen fuel efficiently from natural solar light and water, overcoming the efficiency bottleneck of solar hydrogen production., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Development of a new and green strategy for C(sp 3 )-N bond cleavage is very interesting. Herein, photocatalytic cleavage of the C(sp 3 )-N bond of trialkylamines was achieved, with concurrent formation of dialkylamines and olefins. It was found that a rationally designed 2D-Bi 2 WO 6 @1D-LaPO 4 heterostructure was very efficient for the reaction due to its high light collection efficiency and unique catalytic properties. The strategy could be used for different trialkylamines, including triethylamine, tri-n-propylamine, and ethyl-di-isopropylamine. The mechanistic investigation indicated that the catalyst with heterostructure was not only favorable for charge carrier separation but also rendered excited electrons with high reduction capacity. This work opens a way for C(sp 3 )-N bond cleavage of trialkylamines., (© 2022 Wiley-VCH GmbH.)

Upcycling of carbon dioxide towards fuels and value-added chemicals poses an opportunity to overcome challenges faced by depleting fossil fuels and climate change. Herein, combining highly controllable molecular beam epitaxy growth of gallium nitride (GaN) under a nitrogen-rich atmosphere with subsequent air annealing, a tunable platform of gallium oxynitride (GaN 1-x O x ) nanowires is built to anchor rhodium (Rh) nanoparticles for carbon dioxide hydrogenation. By correlatively employing various spectroscopic and microscopic characterizations, as well as density functional theory calculations, it is revealed that the engineered oxynitride surface of GaN works in synergy with Rh to achieve a dramatically reduced energy barrier. Meanwhile, the potential-determining step is switched from *COOH formation into *CO desorption. As a result, significantly improved CO activity of 127 mmol‧g cat -1 ‧h -1 is achieved with high selectivity of >94% at 290 °C under atmospheric pressure, which is three orders of magnitude higher than that of commercial Rh/Al 2 O 3 . Furthermore, capitalizing on the high dispersion of the Rh species, the architecture illustrates a decent turnover frequency of 270 mol CO per mol Rh per hour over 9 cycles of operation. This work presents a viable strategy for promoting CO 2 refining via surface engineering of an advanced support, in collaboration with a suitable metal cocatalyst., (© 2022. The Author(s).)

The carbon-neutral synthesis of syngas from CO 2 and H 2 O powered by solar energy holds grand promise for solving critical issues such as global warming and the energy crisis. Here we report photochemical reduction of CO 2 with H 2 O into syngas using core/shell Au@Cr 2 O 3 dual cocatalyst-decorated multistacked InGaN/GaN nanowires (NWs) with sunlight as the only energy input. First-principle density functional theory calculations revealed that Au and Cr 2 O 3 are synergetic in deforming the linear CO 2 molecule to a bent state with an O-C-O angle of 116.5°, thus significantly reducing the energy barrier of CO 2 RR compared with that over a single component of Au or Cr 2 O 3 . Hydrogen evolution reaction was promoted by the same cocatalyst simultaneously. By combining the cooperative catalytic properties of Au@Cr 2 O 3 with the distinguished optoelectronic virtues of the multistacked InGaN NW semiconductor, the developed photocatalyst demonstrated high syngas activity of 1.08 mol/g cat /h with widely tunable H 2 /CO ratios between 1.6 and 9.2 under concentrated solar light illumination. Nearly stoichiometric oxygen was evolved from water splitting at a rate of 0.57 mol/g cat /h, and isotopic testing confirmed that syngas originated from CO 2 RR. The solar-to-syngas energy efficiency approached 0.89% during overall CO 2 reduction coupled with water splitting. The work paves a way for carbon-neutral synthesis of syngas with the sole inputs of CO 2 , H 2 O, and solar light.

Design of active catalysts for chemical utilization of methane under mild conditions is of great importance, but remains a challenging task. Here, we prepared a Ag/AgCl with SiO 2 coating (Ag/AgCl@SiO 2 ) photocatalyst for methane oxidation to carbon monoxide. High carbon monoxide production (2.3 μmol h -1 ) and high selectivity (73%) were achieved. SiO 2 plays a key role in the superior performance by increasing the lifetime of the photogenerated charge carriers. Based on a set of semi in situ infrared spectroscopy, electron paramagnetic resonance, and electronic property characterization studies, it is revealed that CH 4 is effectively and selectively oxidized to CO by the in situ formation of singlet 1 O 2 via the key intermediate of COOH*. Further study showed that the Ag/AgCl@SiO 2 catalyst could also drive valuable conversion using real sunlight under ambient conditions. As far we know, this is the first work on the application of SiO 2 modified Ag/AgCl in the methane oxidation reaction., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

The carbon-free production of hydrogen from water splitting holds grand promise for the critical energy and environmental challenges. Herein, few-atomic-layers iron (Fe FAL ) anchored on GaN nanowire arrays (NWs) is demonstrated as a highly active hydrogen evolution reaction catalyst, attributing to the spatial confinement and the nitrogen-terminated surface of GaN NWs. Based on density functional theory calculations, the hydrogen adsorption on Fe FAL :GaN NWs is found to exhibit a significantly low free energy of -0.13 eV, indicative of high activity. Meanwhile, its outstanding optoelectronic properties are realized by the strong electronic coupling between atomic iron layers and GaN(10ī0) together with the nearly defect-free GaN NWs. As a result, Fe FAL :GaN NWs/n + -p Si exhibits a prominent current density of ∼ -30 mA cm -2 at an overpotential of ∼0.2 V versus reversible hydrogen electrode with a decent onset potential of +0.35 V and 98% Faradaic efficiency in 0.5 mol/L KHCO 3 aqueous solution under standard one-sun illumination., Competing Interests: Some IP related to GaN nanowire synthesis was licensed to NS Nanotech, Inc., which was co-founded by Z.M., (© 2020.)

A rational design of an electrocatalyst presents a promising avenue for solar fuels synthesis from carbon dioxide (CO 2 ) fixation but is extremely challenging. Herein, we use density functional theory calculations to study an inexpensive binary copper-iron catalyst for photoelectrochemical CO 2 reduction toward methane. The calculations of reaction energetics suggest that Cu and Fe in the binary system can work in synergy to significantly deform the linear configuration of CO 2 and reduce the high energy barrier by stabilizing the reaction intermediates, thus spontaneously favoring CO 2 activation and conversion for methane synthesis. Experimentally, the designed CuFe catalyst exhibits a high current density of -38.3 mA⋅cm -2 using industry-ready silicon photoelectrodes with an impressive methane Faradaic efficiency of up to 51%, leading to a distinct turnover frequency of 2,176 h -1 under air mass 1.5 global (AM 1.5G) one-sun illumination., Competing Interests: The authors declare no competing interest.

The combination of earth-abundant catalysts and semiconductors, for example, molybdenum sulfides and planar silicon, presents a promising avenue for the large-scale conversion of solar energy to hydrogen. The inferior interface between molybdenum sulfides and planar silicon, however, severely suppresses charge carrier extraction, thus limiting the performance. Here, we demonstrate that defect-free gallium nitride nanowire is ideally used as a linker of planar silicon and molybdenum sulfides to produce a high-quality shell-core heterostructure. Theoretical calculations revealed that the unique electronic interaction and the excellent geometric-matching structure between gallium nitride and molybdenum sulfides enabled an ideal electron-migration channel for high charge carrier extraction efficiency, leading to outstanding performance. A benchmarking current density of 40 ± 1 mA cm -2 at 0 V vs. reversible hydrogen electrode, the highest value ever reported for a planar silicon electrode without noble metals, and a large onset potential of +0.4 V were achieved under standard one-sun illumination.

Photoelectrochemical (PEC) reduction of CO 2 with H 2 O not only provides an opportunity for reducing net CO 2 emissions but also produces value-added chemical feedstocks and fuels. Syngas, a mixture of CO and H 2 , is a key feedstock for the production of methanol and other commodity hydrocarbons in industry. However, it is challenging to achieve efficient and stable PEC CO 2 reduction into syngas with controlled composition owing to the difficulties associated with the chemical inertness of CO 2 and complex reaction network of CO 2 conversion. Herein, by employing a metal/oxide interface to spontaneously activate CO 2 molecule and stabilize the key reaction intermediates, we report a benchmarking solar-to-syngas efficiency of 0.87% and a high turnover number of 24 800, as well as a desirable high stability of 10 h. Moreover, the CO/H 2 ratios in the composition can be tuned in a wide range between 4:1 and 1:6 with a total unity Faradaic efficiency. On the basis of experimental measurements and theoretical calculations, we present that the metal/oxide interface provides multifunctional catalytic sites with complementary chemical properties for CO 2 activation and conversion, leading to a unique pathway that is inaccessible with the individual components. The present approach opens new opportunities to rationally develop high-performance PEC systems for selective CO 2 reduction into valuable carbon-based chemicals and fuels.

The preparation of functional materials and value-added chemicals using biomass-derived feedstocks is an interesting topic. Herein, we propose a method to prepare Ru/graphene catalyst using glucose as the carbon source. The catalyst was characterized by scanning and transmission electron microscopies, Raman and X-ray photoelectron spectroscopies, and X-ray diffraction. It was found that Ru particles of 2-6 nm were supported uniformly on high-quality graphene. The performance of the Ru/graphene for hydrogenation of levulinic acid to γ-valerolactone was studied. The Ru/graphene had much higher activity for the hydrogenation reaction than commercial Ru/C, and was active even at room temperature. The high activity was partially due to the unique structure of graphene, which resulted in an electron-enriched Ru nanocatalyst. In addition, the Ru/graphene could be reused at least four times without considerable decrease in activity, indicating the excellent stability of the catalyst under our conditions., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Direct utilization of the abundant hydrogen and oxygen in water for organic reactions is very attractive and challenging in chemistry. Herein, we report the first work on the utilization of the hydrogen in water for the hydrogenation of various organic compounds to form valuable chemicals and the oxygen for the oxidation of glucose, simultaneously by photocatalysis. It was discovered that various unsaturated compounds could be efficiently hydrogenated with high conversion and selectivity by the hydrogen from water splitting and glucose reforming over Pd/TiO 2 under UV irradiation (350 nm). At the same time, glucose was oxidated by the hydroxyl radicals from water splitting and the holes caused by UV irradiation to form biomass-derived chemicals, such as arabinose, erythrose, formic acid, and hydroxyacetic acid. Thus, the hydrogen and oxygen were used ideally. This work presents a new and sustainable strategy for hydrogenation and biomass conversion by using the hydrogen and oxygen in water.

The utilization of compounds from natural sources to prepare functional materials is of great importance. Herein, we describe for the first time the preparation of organic-inorganic hybrid catalysts by using natural phytic acid as building block. Zirconium phosphonate (Zr-PhyA) was synthesized by reaction of phytic acid and ZrCl4 and was obtained as a mesoporous material with pore sizes centered around 8.5 nm. Zr-PhyA was used to catalyze the mild and selective Meerwein-Ponndorf-Verley (MPV) reduction of various carbonyl compounds, e.g., of levulinic acid and its esters into γ-valerolactone. Further studies indicated that both Zr and phosphate groups contribute significantly to the excellent performance of Zr-PhyA., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)