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This article describes a systematic study of the oxidative etching and regrowth behaviors of Pd nanocrystals, including single‐crystal cubes bounded by {100} facets, single‐crystal octahedra and tetrahedra enclosed by {111} facets; and multiple‐twinned icosahedra covered by {111} facets and twin boundaries. During etching, Pd atoms are preferentially oxidized and removed from the corners regardless of the type of nanocrystal, and the resultant Pd2+ ions are then reduced back to elemental Pd. For cubes and icosahedra, the newly formed Pd atoms are deposited on the {100} facets and twin boundaries, respectively, due to their relatively higher energies. For octahedra and tetrahedra, the Pd atoms self‐nucleate in the solution phase, followed by their growth into small particles. We can control the regrowth rate relative to etching rate by varying the concentration of HCl in the reaction solution. As the concentration of HCl is increased, 18‐nm Pd cubes are transformed into octahedra of 23, 18, and 13 nm, respectively, in edge length. Due to the absence of regrowth, however, Pd octahedra are transformed into truncated octahedra, cuboctahedra, and spheres with decreasing sizes whereas Pd tetrahedra evolve into truncated tetrahedra and spheres. In contrast, Pd icosahedra with twin boundaries on the surface are converted to asymmetric icosahedra, flower‐like icosahedra, and spheres. This work not only advances the understanding of etching and growth behaviors of metal nanocrystals with various shapes and twin structures but also offers an alternative method for controlling their shape and size. [ABSTRACT FROM AUTHOR]

Charge transfer in a semiconductor is crucial for photocatalytic pure water splitting. Herein, we construct a series of P-doped- g -C 3 N 4 /Fe 2 P/red-P (PCN/Fe 2 P/RP) ternary composite by in-situ phosphorization of a Fe 2 O 3 @C/ g -C 3 N 4 heterojunction. The as-prepared composite show substantially improved photocatalytic activity toward pure water splitting under visible light irradiation without adding any noble metal. The optimized composite containing 15 wt% Fe 2 P presents the best activity, with the H 2 production rate of 429 µmol g−1 h−1, which is 107 and 39 times higher than that of pristine g-C 3 N 4 and P doped g -C 3 N 4 (PCN), respectively. This noble-metal-free photocatalyst presents a solar-to-hydrogen conversion efficiency of about 0.2% for pure water splitting. It is found that water splitting proceeds via a two-electron pathway with simultaneous production of H 2 and H 2 O 2. The improvement relies on the formation of intermediate Fe 2 P for rapid Z-scheme electron transfer from the midgap state of PCN to the valence band of RP. This work provides a versatile method for fabricating noble-metal-free photocatalyst with controlled charge transfer behavior for efficient photocatalytic pure water splitting. [Display omitted] • Efficient P-doped- g -C 3 N 4 /Fe 2 P/red-P photocatalyst is successfully prepared. • Photocatalytic pure water splitting is achieved by two-election Z-scheme mechanism. • Fe 2 P acts as an intermediate layer for rapid Z-scheme electron transfer. • Solar-to-hydrogen conversion efficiency of the composite is about 0.2%. [ABSTRACT FROM AUTHOR]

Localized surface plasmon resonance (LSPR) has drawn much interest in photocatalysis due to the advantages in extending light-absorption and improving charge-separation efficiency. In this work, Au nanocubes with exposed {100} facets and Au nanotrioctahedrons with exposed {221} facets are synthesized via the seed-growth method with the aim of demonstrating the photocatalytic performance under the LSPR effect using a typical TiO2 photocatalyst. The modification of Au nanocrystals results in accelerated charge separation in the TiO2 photocatalyst, which is attributed to the synergetic effect of local electromagnetic field enhancement from the LSPR effect and the Schottky junction established in Au and TiO2. Consequently, the photocatalytic hydrogen-production from the TiO2 photocatalyst is greatly improved. Moreover, Au nanotrioctahedrons modified TiO2 exhibits superior photocatalytic performance due to the stronger local electromagnetic field of the LSPR and the more efficient electron trapping originated from the unique morphology with exposed {221} facets. [ABSTRACT FROM AUTHOR]

Z-scheme photocatalysis provides a promising solution to photocatalytic solar water splitting, yet restricted by inferior interfacial charge transfer. Here, we demonstrate a Z-scheme composite photocatalyst made of Fe 2 O 3 , a carbon layer, and g-C 3 N 4 that can achieve efficient hydrogen generation from solar water decomposition. The success relies on in-situ preparation of core-shell Fe 2 O 3 @C structure at the surface of g-C 3 N 4. Carbon as an intermediate layer thus acts as a bridge that significantly accelerates the migration of photogenerated electrons from Fe 2 O 3 conduction band to g-C 3 N 4 valence band. As a result, the highest rate of H 2 generation reaches 5.26 mmol h−1g−1. This activity is approximately 33-time greater than that achieved over pristine g-C 3 N 4 and about 4-time larger than that obtained over a Fe 2 O 3 /g-C 3 N 4 heterojunction without internal carbon layer. This work explicates the potential insight of the composite and paves a promising way to engineer the charge transfer behavior. [Display omitted] • A heterojunction made of Fe 2 O 3 , g-C 3 N 4 , and a carbon interlayer is obtained. • Photocatalytic water splitting proceeds via a Z-scheme mechanism over the catalyst. • The intermediate carbon layer acts as a channel for efficient electron transfer. • The photocatalytic activity for H 2 production is significantly improved. [ABSTRACT FROM AUTHOR]

The aggregate structures of photocatalyst particles are critical for their light absorption and scattering properties and thus significantly impact the photocatalytic performance toward solar hydrogen production. Herein, taking P25 TiO 2 nanoparticles as model photocatalysts, we calculate the optical properties of the aggregates of nanoparticles with the Discrete Dipole Approximation (DDA). A scattering phase function, which can reveal and predict the structural information of photocatalyst particles, is accordingly obtained. Specifically, it is found that the forward scattering is dominant when light is scattered on the particles, and this scattering mode becomes more intense with the increment of the particle size. Our results show that the scattering phase function is also in agreement with the Rayleigh-Gans-Debye (RGD) approximation. • Clusters of TiO 2 nanoparticles are established via fractal aggregation models. • Scattering properties are calculated via Discrete Dipole Approximation. • Forward-scattering dominates the phase function in modeling photocatalysis. • Phase functions agree with the prediction of Rayleigh-Gans-Debye approximation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ultrathin TiO 2 shell was coated on chalcogenide nanorod as a protecting layer. • The synthesis relies on kinetic control for layer-by-layer deposition of TiO 2. • The heterostructure enables superior activity and stability of solar H 2 evolution. • Charge transfer is controlled by type-II band alignment and tunneling effect. Abstract It has been a subject of intensive research on avoiding photocorrosion of sulfide photocatalysts while retaining their activity for visible-light-driven photocatalysis. Herein, using Cd 0.9 Zn 0.1 S (CZS) nanorod as an example, we report an effective strategy based upon conformal coating of an ultrathin pinhole-free TiO 2 shell, with controllable thickness from 2 to 7 nm, on the nanorod as protecting layer. The synthesis relies on the use of a syringe pump for kinetic control, by which, TiO 2 can grow on the surface of CZS in a layer-by-layer mode. The core–shell heterostructures were found with excellent photocatalytic performance toward solar hydrogen production from a Na 2 S-Na 2 SO 3 aqueous solution. The reaction can stably proceed for 200 h without notable decay of the hydrogen evolution rate. A volcano-type relationship between the mass activity and the shell thickness was gained either in the presence of a cocatalyst or not. The heterostructure with a shell thickness of 2 nm presented the highest H 2 -evolution activity with a quantum efficiency of 19%. However, the one with a shell thickness of 7 nm, instead, was found to be more active, with a quantum efficiency reaching 44%, when 1 wt% NiS x cocatalyst was introduced. It is believed that photogenerated electrons transfer from CZS to TiO 2 , while the holes vanish via quantum-tunneling-induced recombination with the electrons. This work suggests that sulfide photocatalysts with desirable efficiency and corrosion resistance could be achieved by introducing conformal atomic TiO 2 layers. [ABSTRACT FROM AUTHOR]

The feasibility of solar hydrogen production from water has long relied on the activity and stability of a given photocatalyst. In this study, using Cd x Zn 1-x S as a model photocatalyst, we demonstrated that the activity and stability of chalcogenide photocatalyst could be readily adjusted by changing the reaction conditions, including sacrificial reagents, reaction temperature. Our results showed that the combined use of proper sacrificial reagents play a key role against photocorrosion. Under optimized reaction conditions, the photocatalyst remained stable for more than 500 h. Under irradiation from a simulated sun light (light intensity: 789.92 W/m 2 ), the average rate of hydrogen evolution reached 1.43 mmol/h with an energy conversion efficiency from solar to hydrogen of 6.22%. [ABSTRACT FROM AUTHOR]

We offer new insights into the roles played by surface capping in controlling the pattern of growth involving Pd cubic seeds and a HAuCl4 precursor. The final products can take different surface structures (concave vs. flat side faces) depending on the presence or absence of surface capping. [ABSTRACT FROM AUTHOR]

Abstract: A series of CdS and CdS/CNTs photocatalysts were successfully prepared by hydrothermal method and they were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV–visible optical absorption spectra (UV–Vis), etc. By studying their photocatalytic properties, it is found that, for CdS, photocatalysts prepared in appropriate alkaline environment presented higher hydrogen production activity, reaching 794.6 μmol h−1 g−1; the photocatalytic activity of CdS was obviously enhanced by combining it with CNTs via a special two-step hydrothermal method, and the corresponding hydrogen production rate reached 1.771 mmol h−1 g−1; the photocatalytic activity was further improved by loading co-catalyst NiS, achieving 12.13 mmol h−1 g−1. [Copyright &y& Elsevier]

Abstract: A series of Mn2+ doped CdS photocatalysts were prepared by a co-precipitation method and characterized by XRD, DRS, TEM, and XPS techniques. While the band gap, crystal phase and the morphology of CdS nanocrystal were not found to be affected noticeably by Mn2+ doping, there was an optimal Mn2+ doping content of wt 0.5% where the hydrogen production was more than doubled compared to pure CdS. Calculations of density functional theory (DFT) with plane waves and pseudopotentials were used to characterize the doping effect of Mn in cubic CdS. It is assumed that Mn2+ serving as shallow trapping sites can separate e−/h+ pairs at surface of nanosized CdS, so as to greatly reduce their surface recombination and which in turn leads to improved hydrogen yield. [Copyright &y& Elsevier]

Abstract: Hydrogen production under visible light by photocatalytic reforming of glucose over an oxide solid solution photocatalyst BixY1−xVO4 (BYV) was demonstrated for the first time. It was found that a certain amount of Y doping would promote the transition of BiVO4 from monoclinic to tetragonal phase and finally lead to the formation of tetragonal BYV solid solution. BYV with a B/Y ratio of 1:1 showed the highest activity for hydrogen production. The amount of photoproduced hydrogen lowered after several hours of reaction. However, when the gas product was replaced with N2 atmosphere, hydrogen production recovered. It is supposed that the generated CO2 might participate in the redox reaction and in some way inhibit the hydrogen production. Therefore, for photocatalytic reforming of glucose, removal of gas product in time is indispensable. [ABSTRACT FROM AUTHOR]

Ni doped ZnInS microsphere with flower-like nanoscale petals were prepared by a hydrothermal method. There was an optimal Ni doping content of 0.3 wt% where hydrogen production reached the maximum. Higher Ni doping can hardly dope into the ZnInS lattice and just stay at ZnInS surface, leading to decreased activity. It was determined that Ni entering the ZnInS lattice instead of surface NiS dominated the enhanced photocatalytic activity. The experimental results were rationalized by assuming Ni serving as shallow trapping sites, greatly enhancing the activity of the photocatalyst. Graphical Abstract: Ni doped ZnInS microsphere with flower-like nanoscale petals were prepared by a hydrothermal method. There is an optimal Ni doping content of 0.3 wt% where hydrogen production reached the maximum. It is assumed that Ni serving as shallow trapping sites can separate the arrival time of e/h pairs at the petal surface of ZnInS, so as to greatly reduce their surface recombination and which, in turn, leads to improved hydrogen production.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: Decahedral Cu2WS4 was synthesized by a facile hydrothermal method and employed as photocatalyst for photocatalytic hydrogen production for the first time. The hydrothermal method avoids the traditional use of H2S for the preparation of such chalcogenide, which guarantees an environmental-friendly process. The properties of the Cu2WS4 samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–Vis reflectance spectra, etc. The results showed that the decahedral Cu2WS4 possessed a band gap of ca. 2.1ev. The photocatalyst was demonstrated to be very active under visible light for hydrogen production. Especially, Cu2WS4 synthesized at 200 °C for 72 h showed the highest activity with the apparent quantum yield of 11% at 425 nm. The correlation between the preparation parameters and the photocatalytic properties were investigated. It was expected this first report of W-based chalcogenide photocatalyst would add to the photocatalyst group and lead to the finding of new photocatalyst with much higher activity. [ABSTRACT FROM AUTHOR]

Abstract: A novel catalyst-fixed way is present. And two series of novel CdS-incorporated special glass composite photocatalysts working under visible light were successfully prepared in this way by a two-step thermal sulfidation procedure for the use of catalyst-fixed system. One was by a high temperature way, and the other was by a low temperature way. The composite photocatalysts with different content of CdS prepared by the methods were found to show a good activity for the decomposition of water under visible light. The highest rate of H2 revolution is 1549μmol/(hgCdS) with wt1%-Pt loaded. The composites prepared by high and low temperature were characterized by X-ray diffraction (XRD), diffuse reflectance UV–vis spectra and scanning electron microscopy (SEM). The as-prepared photocatalysts exhibited different photochemical and photophysical properties for the combined way between glass-base and CdS. The photochemical and photophysical properties were very important in the catalyst-fixed system used for large-scale hydrogen production. [Copyright &y& Elsevier]

Abstract: Dendritic cells (DCs) orchestrate a repertoire of immune responses that endows resistance to infection and tolerance to self. Understanding the principles by which DCs control immunity and tolerance has provided a rich basis for studying and improving clinical outcome of human disease treatment. Several features contribute to the complexity of the DC system. Among these, plasticity and existence of subsets are prominent determinants to the quality of the elicited immune responses. Indeed, different DC subsets are distributed in peripheral tissues and the blood and display different microbial receptors, surface molecules and cytokine expression, all of which influence the immunologic outcome. The biologic raison d''être for separate DC subsets has been the focus of many studies including our own and is being reviewed with an emphasis on human skin DCs. [Copyright &y& Elsevier]

• Monodispersed HCSs with tunable cavity size were synthesized through a thermal-etching process without template. • The "inside-out" oriented thermal etching process was induced by the "core-shell" differentiated chemical structures of CSs. • HCSs exhibited a SISG efficiency as high as 88.9%, which outperforms most of the previously reported carbon-based materials. • The delicate heat management contributes to the significantly improved SISG efficiency. Hollow carbon spheres (HCSs) with controllable morphology and structure have received considerable attention in the field of energy conversion and storage. Herein, monodispersed HCSs with cavity sizes tuned from 100 nm to 800 nm and shell thickness from 450 nm to 50 nm were successfully synthesized through a unique template-free thermal-etching method. It was evidenced that the dynamically controllable synthesis of HCSs was attributed to the "inside-out" oriented thermal oxidation etching of carbon spheres (CSs) induced by the differentiated "core-shell" chemical structures. Comparing to CSs, the obtained HCSs exhibited much increased efficiency for solar-driven interfacial steam generation (SISG), reaching as high as 88.9%, which outperforms most of the previously reported carbon-based materials. It was then demonstrated that the rational heat management for both photothermal and thermal-evaporation conversion is essential to achieve satisfying SISG efficiency. Depending on the increasing cavity sizes, HCSs presented gradual increases in both photothermal conversion and thermal-evaporation performances, mainly attributed to the improved light absorption and the delicate heat management, respectively. However, the further increase in cavity size resulted in excessive heat loss and presented decreased thermal-evaporation performance. This work provides an alternative and promising approach to the reasonable design of hollow nanostructures with delicate heat management for efficient SISG as well as other solar energy conversion applications. Hollow carbon spheres with tunable cavity was synthesized by an oriented thermal etching of hydrothermally synthesized carbon spheres, which exhibited excellent solar steam generation performances, with delicate heat management in both photothermal conversion and thermal-evaporation processes. [Display omitted] [ABSTRACT FROM AUTHOR]

We report a photocatalytic system that utilizes Cd 0.5 Zn 0.5 S nanotwins decorated with various Ni-based co-catalysts for solar-driven hydrogen production through lignocellulose reformation. In this noble-metal-free system, Ni(OH) 2 emerges as the most effective Ni form in enhancing the photocatalytic evolution of H 2. By optimizing the composition with 3 wt% Ni(OH) 2 loading, we achieved the highest activity, with the hydrogen production rates of 7.00 mmol g−1 h−1 and 1.97 mmol g−1 h−1 from α-cellulose and waste straw photoreforming, respectively. This optimized composition exhibited the highest quantum efficiency of 7.68%. In principle, the lower potential of Ni2+/Ni compared to the conduction band of Cd 0.5 Zn 0.5 S facilitates the transfer of electrons from the conduction band of Cd 0.5 Zn 0.5 S to Ni(OH) 2. Specifically, during the photocatalytic reaction, a fraction of surface Ni(OH) 2 is reduced to Ni. The in-situ formed Ni clusters, along with the Ni(OH) 2 , enhance the separation photogenerated electrons and facilitate their transfer to H+, leading to significantly improved photocatalytic activity. This work not only provides an effective strategy for developing more efficient photocatalysts, but also offers a direct means of harnessing clean energy from abundant waste biomass on Earth. • Ni(OH) 2 /Ni atoms or clusters can serve as co-catalysts enhance the hydrogen production activity of Cd 0.5 Zn 0.5 S. • The cellulose/lignocellulose photoreforming system exhibits exceptional H 2 production efficiency. • The photothermal effect of the Ni(OH) 2 /Cd 0.5 Zn 0.5 S photocatalyst enhances the reaction activity. [ABSTRACT FROM AUTHOR]

• SCN2A rs2304016 AG genotype more prevalent in the VPA-resistant group in Chinese children with epilepsy. • In subgroup of focal seizure, SCN1A rs2298771 AG carriers showed lower incidence of VPA resistance than AA carriers. • SCN2A rs2304016 and SCN1A rs2298771 polymorphisms might be associated with the VPA response in epileptic children. This study was conducted to explore the influence of genetic variations on responsiveness to valproic acid (VPA) monotherapy among Chinese children with epilepsy. One hundred and forty epileptic children taking VPA as monotherapy were enrolled, and at least one-year follow-up was obtained to assess the therapeutic outcome. Twenty-seven single nucleotide polymorphisms (SNPs) within twelve candidate genes correlated with the metabolic enzymes, transporters and targets of VPA were genotyped. The effects of selected polymorphisms on VPA efficacy were identified by binary logistic regression analysis adjusting for potential confounders. SCN2A rs2304016 (A > G) AG genotype was more common among the VPA-resistant patients in comparison with the VPA-responsive patients (OR = 3.18, 95 % CI = 1.10−9.14, P = 0.032), and in subgroup of focal seizure, lower frequency of VPA resistance was found in epileptic children with SCN1A rs2298771 AG genotype than those with AA genotype (OR = 0.11, 95 % CI = 0.01−0.91, P = 0.040). Our study indicated that SCN2A rs2304016 and SCN1A rs2298771 polymorphisms might be associated with the response to VPA monotherapy in Chinese epileptic children. Further and larger researches are required to validate these results. [ABSTRACT FROM AUTHOR]

Comprehensive Summary We present a facile synthetic strategy to create mesoporous Cu2O nanocrystals with tunable pore structures and surface functional groups of amine derivatives for efficient and preferable electrochemical conversion of CO2 into ethylene. The structural characteristics of these Cu2O nanocrystals can be manipulated using a set of amine derivatives, such as pyridine, 4,4'‐bipyridine, and hexamethylenetetramine, during the oxidative etching process of Cu nanocrystals by bubbling gaseous oxygen in N,N‐dimethylformamide solution. These amine derivatives not only serve as surface functional groups but also significantly affect the resulting pore structures. The synergistic effect of pore structure confinement and surface amine functionalization leads to the superb Faradaic efficiency (FE) of 51.9% for C2H4, respectively, together with the C2H4 partial current density of –209.4 mA·cm−2 at –0.8 V vs. reversible hydrogen electrode (RHE). The relatively high selectivity towards C2H4 was investigated using DFT simulations, where 4,4'‐bipyridine functionalized Cu2O seemed to favor the C2H4 formation with the low free energy of the intermediates. This study provides a feasible strategy to manipulate the pore structure and surface functionalization of mesoporous Cu2O nanocrystals by regulating the oxidative etching process, which sheds light on the rational preparation of high‐performance CO2RR electrocatalysts. [ABSTRACT FROM AUTHOR]

In the ZINC20 database, with the aid of maximum substructure searches, common substructures were obtained from molecules with high-strain-energy and combustion heat values, and further provided domain knowledge on how to design high-energy-density hydrocarbon (HEDH) fuels. Notably, quadricyclane and syntin could be topologically assembled through these substructures, and the corresponding assembled schemes guided the design of 20 fuel molecules (ZD-1 to ZD-20). The fuel properties of the molecules were evaluated by using group-contribution methods and density functional theory (DFT) calculations, where ZD-6 stood out due to the high volumetric net heat of combustion, high specific impulse, low melting point, and acceptable flash point. Based on the neural network model for evaluating the synthetic complexity (SCScore), the estimated value of ZD-6 was close to that of syntin, indicating that the synthetic complexity of ZD-6 was comparable to that of syntin. This work not only provides ZD-6 as a potential HEDH fuel, but also illustrates the superiority of learning design strategies from the data in increasing the understanding of structure and performance relationships and accelerating the development of novel HEDH fuels. [ABSTRACT FROM AUTHOR]

Noble-metal nanocrystals with structural features such as high-index facets and twin defects on the surface are desirable for various catalytic applications. Here we report an aqueous route to the facile synthesis of Pd–M (M = Pd, Pt, and Au) decahedra covered with concave facets by controlling the deposition and diffusion of M atoms on Pd decahedral seeds. Our mechanistic studies indicate that the preferential deposition of M atoms on the twin boundaries of Pd decahedral seeds under limited surface diffusion is instrumental to their evolution into decahedra enclosed by concave facets. Due to the presence of high-index facets and twin boundaries on the surface, the Pd concave decahedra show enhanced catalytic activity towards formic acid oxidation. The present work not only offers a general route to the facile synthesis of decahedral nanocrystals with concave facets but also provides an additional knob for enhancing the catalytic performance of noble-metal nanocrystals. [ABSTRACT FROM AUTHOR]

We report the design and synthesis of two kinds of amphiphilic Janus SiO 2 nanoparticles, including polyacrylic acid/polystyrene (PAA/PS) Janus SiO 2 and polyacrylic acid/polymethylmethacrylate (PAA/PMMA) Janus SiO 2. The amphiphilic Janus SiO 2 nanoparticles can effectively stabilize polystyrene butyl acrylate (P(St-BA)) composite microspheres, forming low-cost oil displacing systems to improve the oil recovery of heterogeneous and low-permeability reservoirs. Among them, the PAA/PS Janus SiO 2 stabilized P(St-BA) are demonstrated with good injection, migration, and plugging performance, as well as high temperature and salt resistance. These advantages enable the system an oil recovery increment of 32%. In addition, the microspheres also present good enhanced oil recovery potential in heterogeneous reservoirs, especially for cores with a permeability ratio of 2.0. In principle, the oil displacement of this system is achieved by the synergic effect of amphiphilic Janus SiO 2 nanoparticles and composite microspheres. This work thus provides a promising method for high-performance yet low-cost oil recovery improvement. [Display omitted] • Two kinds of amphiphilic Janus SiO 2 were designed and synthesized to stabilize P(St-BA) microspheres, forming low-cost oil displacing systems. • PAA/PS Janus SiO 2 stabilized P(St-BA) demonstrated excellent profile control and oil displacing performance with a 32% oil recovery increment. • The synergistic effect of composite microspheres and amphiphilic Janus SiO 2 nanoparticles in the aqueous dispersion achieved enhanced oil recovery. [ABSTRACT FROM AUTHOR]

We report the synthesis of a Z-scheme monolithic photocatalyst in the form of copper foam (CF) supported TiO 2 combining Cu 2 O and Ag nanoparticles (CF@TiO 2 /Cu 2 O-Ag). The designed catalysts with efficient charge separation show superior photocatalytic activity toward CO 2 reduction, with a maximum CO yielding rate of 25.58 μmol‧g-1‧h-1. More importantly, we develop a solar-wind energy complementary device, which enables the strong coupling of the magnetic field into the photocatalytic reaction. Specifically, the in-situ space electric field generated from the wind-driven induced electromotive force further enhances the separation and transportation of photogenerated charge carriers in the Z-scheme system. The productivity of CO in the proof-of-concept device based on the use of CF@TiO 2 /Cu 2 O-Ag catalyst reaches 71.66 μmol‧g-1‧h-1. This study provides an ideal approach for reinforcing photocatalytic CO 2 reduction through muti-field coupling and highlights the prospect of solar-wind energy coupled photocatalysis. [Display omitted] • Preparation of monolithic Z-scheme CF@TiO 2 /0.6Cu 2 O-0.6Ag photocatalyst. • Z-scheme heterostructure enables effective carrier transportation and separation. • Loading of Cu 2 O and Ag promotes photoreduction of CO 2 into CO. • Construction of environmental friendliness solar-wind photocatalytic reactor. • Induced electromotive force raised from magnetic field boosts charge separation. [ABSTRACT FROM AUTHOR]

Gold–silver (Au–Ag) nanocrystals with a combination of concave surface and hollow interior are of great interest due to their distinctive structural merits. Herein, we introduce a facile strategy based on seed surface doping to create concave Au@AuAg yolk–shell nanocubes with surface concavity (Au@AuAg YSCNCs), and examine their intriguing properties in optics and catalysis. In particular, the Au@Ag core–shell nanocubes are generated and reacted with sodium thiosulfate, followed by the addition of HAuCl4 to remove Ag atoms on the side walls and deposit Au/Ag atoms on the corners/edges via the galvanic replacement reaction. UV-vis extinction spectra show that compared to Au@Ag core–shell nanocubes, the current Au@AuAg YSCNCs enable a redshift in the major absorption peak, which should be attributed to the increase in charge polarization regions. Meanwhile, the structural advantage is validated using the reduction of 4-nitrophenol as the model reaction. In particular, the current Au@AuAg YSCNCs exhibit an enhanced catalytic efficiency compared to the Au@Ag core–shell nanocubes. Mechanism study using density functional theory reveals that the structural advantage boosts the catalytic activity by upshifting the d-band center and thus lowering the activation barrier. The current study provides a feasible strategy to integrate two structural features (e.g., concave surface and hollow interior) into one AuAg nano-entity, which could be potentially extended to other metals and/or alloys. [ABSTRACT FROM AUTHOR]

Ta3N5 is a promising material for photocatalytic hydrogen production from water because of its suitable band structure for both solar energy collection and overall water splitting, while its application is restricted by severe charge recombination as well as non‐equilibrium redox capabilities. Herein, atomic‐scale N‐doped NaTaO3@Ta3N5 (NNaTaO3@Ta3N5) core‐shell cubes prepared by nitridation of cubic NaTaO3 are reported. The core‐shell heterojunction cubes present efficient and stoichiometric evolution of H2 and O2 from photocatalytic overall water splitting, with a quantum efficiency of 2.18% at 550 nm without any cocatalyst. The success relies on the Ta3N5 shell having a thickness of only ≈5 nm which enables increased lifetimes of the photogenerated charges. Moreover, the core‐shell heterojunction shows a type‐I band alignment that can steer smooth charge flow from NNaTaO3 to Ta3N5, particularly with the assistance of the shared communal Ta atoms at the interface. This efficiency can be further improved to 6.28% by in situ deposition of a Rh@Cr2O3 core‐shell cocatalyst, which is among the highest reported values over Ta3N5‐based photocatalyst. This study offers a promising pathway for the construction of well‐defined heterojunctions with manipulated charge transfer behavior for photocatalytic overall water splitting. [ABSTRACT FROM AUTHOR]

The ability to create highly active and CO‐tolerant platinum‐free catalysts toward alkaline hydrogen oxidation reaction (HOR) represents a significant endeavor to enable commercialization of alkaline fuel cells. This, however, remains a grand challenge. Herein, a robust defective‐carbon‐supported Ru catalyst (denoted as Ru@C) is crafted to achieve efficient and CO‐tolerant HOR in alkaline media via delicately tailoring interfacial chemistry of catalyst. Notably, the degree of defects in the carbon support is the key to tune the interface chemistry. An integrated experimental and density functional theory calculations study demonstrates that the favorable interfacial chemical interaction between Ru and carbon support controlled by the covalently bonded Ru─O─C redistributes the d electrons of Ru and downshiftsits d‐band center, which in turn weakens the hydrogen adsorption and suppresses the Ru 4d→CO 2π* back donation. Consequently, the optimized Ru@C catalyst renders a 6.6‐fold enhancement in mass activity (@25 mV) for alkaline HOR over the conventional Ru/C counterpart, which also outperforms the state‐of‐the‐art catalysts. Intriguingly, the catalyst can tolerate 20 000 ppm CO, far exceeding that of commercial Pt/C and PtRu/C catalysts. This work elucidates the correlation between precisely tailored interfacial chemistry and HOR performance, and is expected to further enlighten the design of advanced catalysts. [ABSTRACT FROM AUTHOR]

Solar photocatalytic hydrogen production from water has been regarded as an ideal way addressing world energy and environmental crises. The technology has long relied on the development of an efficient photocatalyst. In addition to its photocatalytic performance, the large-scale production of certain photocatalyst from the viewpoint of particle application remains a challenge yet has received insufficient focus. Herein, we report an efficient and practical batch preparation system based upon hydrothermal method to the scalable production of chalcogenide nanoparticle photocatalyst. Taking the synthesis of Cd 0.5 Zn 0.5 S (CZS) twinned photocatalyst as an example, the outcome of CZS photocatalyst could reach ∼0.8 kg in this batched synthesis, which is about 390 times of the lab-scale production in mass amount. It was found that the twinned structure and visible-light absorption property were well maintained. Although further measurements toward the photocatalytic activity indicate slight decrement on solar H 2 generation compared to the lab-scale synthesized CZS photocatalyst, a high quantum efficiency of about 40.5% at 425 nm remained. The photocatalytic reaction could also stably proceed for 200 h without notable decay of H 2 -evolution rate. This work thus provides a powerful means for facile scaling up the chalcogenide nanoparticle photocatalyst at the kilogram level with both high quality and good reproducibility. [ABSTRACT FROM AUTHOR]

Controversies on the surface termination of α-Fe2O3 (0001) focus on its surface stoichiometry dependence on the oxygen chemical potential. Density functional theory (DFT) calculations applying the commonly accepted Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional to a strongly correlated system predict the best matching surface termination, but would produce a delocalization error, resulting in an inappropriate bandgap, and thus are not applicable for comprehensive hematite system studies. Besides, the widely applied PBE+U scheme cannot provide evidence for existence of some of the successfully synthesized stoichiometric α-Fe2O3 (0001) surfaces. Hence, a better scheme is needed for hematite DFT studies. This work investigates whether the strongly constrained and appropriately normed (SCAN) approximation reported by Perdew et al. could provide an improved result for the as-mentioned problem, and whether SCAN can be applied to hematite systems. By comparing the results calculated with the PBE, SCAN, PBE+U, and SCAN+U schemes, we find that SCAN and SCAN+U improves the description of the electronic structure of different stoichiometric α-Fe2O3 (0001) surfaces with respect to the PBE results, and that they give a consistent prediction of the surface terminations. Besides, the bulk lattice constants and the bulk density of states are also improved with the SCAN functional. This study provides a general characterization of the α-Fe2O3 (0001) surfaces and rationalizes how the SCAN approximation improves the results of hematite surface calculations. [ABSTRACT FROM AUTHOR]

An ideal model composite made of CuS nanosheet (photothermal material) and g-C 3 N 4 was constructed through in-situ assembly procedure, along with integration of dual photochemical effect and photothermal effect. Consequently, optimized CN/CuS composite approaches remarkable photocatalytic performance improved by 44.5 times with regarding to that of pristine CN. This superiority can be assignable to inherent characteristic of CuS as photochemical component, with improved charge separation and enriched surface active-sites. Additionally, the critical contribution of photothermal effect in boosting water photosplitting was also experimentally validated. CuS nanosheet as hot spots enables rapid temperature increment around photocatalysts under visible/near-infrared (NIR) light irradiation. The heat converted from solar is conducive to increase carrier density, accelerate carrier mobility, alleviate onset potential and facilitate surface redox kinetics, so as to promote photocatalytic activity. It is believed that synergetic incorporation of photothermal and photochemical conversion could be expanded to other photocatalytic systems towards effective solar energy conversion. • CuS hot spot was integrated with g-C 3 N 4 in 2D-2D contact by in-situ assembly method. • CuS induced photothermal effect plays a critical role in boosting photocatalytic rate. • Photochemical/photothermal synergistic catalysis boosts H 2 evolution by 44.5 times. [ABSTRACT FROM AUTHOR]

Shape-controlled synthesis of semiconductor nanocrystals enables fine manipulation over their physicochemical properties. In this paper, unique Cd 0.9 Zn 0.1 S tetrapod nanostructures consisting of two different polymorphisms, i.e. , wurtzite and zinc blende, were successfully synthesized via a simple ethylenediamine-assisted solvothermal route. It is found that the temperature determines the formation of the zinc blende-structured seeds, while the ethylenediamine facilitates the subsequent preferential growth of the wurtzite phase arms. Furthermore, the tetrapods, characterized by a type-II staggered band alignment, have shown enhanced photocatalytic performance for H 2 generation from an aqueous solution containing electron donors under visible light irradiation, in comparison to the nanocrystals with distinct morphologies. Our results indicate that coupling different polymorphisms in a nanocrystal may be advantageous for photocatalytic proton reduction over single-crystal photocatalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] Due to structural tunability, high surface area, abundant pore structures, and abundant active sites, covalent heptazine frameworks (CHFs) constructed from heptazine and other molecular blocks are especially prominent. Here, we proposed a reaction-dependent strategy for designing two dimensional CHFs including high-throughput precursors screening, structure generation, and performance evaluation. Assuming that oxamide-like precursors can undergo the same thermal polymerization reaction as producing C 6 N 7 , seven precursors were screened from more than 109 molecules in the ZINC20 database in terms of molecular weight, number of substructures, shape index, and symmetry. Furthermore, CHF-L1 to CHF-L7 were constructed from urea and the seven precursors according to the topologically assembling scheme in thermal polymerization. The designed CHFs had band gaps ranging from 1.89 to 3.10 eV. Among them, CHF-L3 assembled structurally by urea and 1,2,4,5-tetrazine-3,6-dicarboxamide with the smallest bandgap and an oxidative potential bias of 1.38 V for oxygen evolution reaction was screened as the candidate with high oxidative ability. The negative formation energy based on the synthesis route indicated the synthetic feasibility of CHF-L3, and negative cohesive energy as well as the stable structure under ab initio molecular dynamics simulations confirmed the stability of CHF-L3. The present work is expected to provide a powerful design strategy for two-dimensional CHFs design and is broadly applicable to various computational covalent organic framework design systems and experimental studies. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Heterojunction design in a two‐dimensional (2D) fashion has been deemed beneficial for improving the photocatalytic activity of g‐C3N4 because of the promoted interfacial charge transfer, yet still facing challenges. Herein, we construct a novel 2D/2D Cu3P nanosheet/P‐doped g‐C3N4 (PCN) nanosheet heterojunction photocatalyst (PCN/Cu3P) through a simple in‐situ phosphorization treatment of 2D/2D CuS/g‐C3N4 composite for photocatalytic H2 evolution. We demonstrate that the 2D lamellar structure of both CuS and g‐C3N4 could be well reserved in the phosphorization process, while CuS and g‐C3N4 in‐situ transformed into Cu3P and PCN, respectively, leading to the formation of PCN/Cu3P tight 2D/2D heterojunction. Owing to the large contact area provided by intimate face‐to‐face 2D/2D structure, the PCN/Cu3P photocatalyst exhibits significantly enhanced charge separation efficiency, thus achieving a boosted visible‐light‐driven photocatalytic behavior. The highest rate for H2 evolution reaches 5.12 μmol·h–1, nearly 24 times and 368 times higher than that of pristine PCN and g‐C3N4, respectively. This work represents an excellent example in elaborately constructing g‐C3N4‐based 2D/2D heterostructure and could be extended to other photocatalyst/co‐catalyst system. [ABSTRACT FROM AUTHOR]

Context: Isomerization processes between glucose and fructose catalyzed by four different organic ligands are investigated with quantum chemistry methods in this study. These organic ligands are the carboxylic pendant group, sulfonic pendant group, amino pendant group, and 1H-imidazole ligand. After guessing and verifying a variety of elementary reactions, transition states and energy barriers that are relevant to the optimum pathways have been confirmed. The effective barriers under the catalysis of the carboxylic pendant group, sulfonic pendant group, amino pendant group, and 1H-imidazole ligand are 97.5 kJ mol−1, 134.7 kJ mol−1, 146.7 kJ mol−1, and 167.7 kJ mol−1, respectively. Then, based on the conclusions of the non-solvation model, the effective barriers in solvents are briefly investigated. The implicit model predicts that solvents bring little improvement or setback to catalyzed reaction models. The explicit model shows that the proton transfer with the participant of water molecules can improve the catalytic performance of Lewis bases in these reactions. The detailed reaction mechanism combing and reliable reaction templates provided in this work will be useful for catalysis designs for glucose transformation to fructose. Methods: This work used the computational level of ωB97M-D3BJ/def2-SVP and the software package of ORCA 4.2. For solvent effects, energies of the gas phase were corrected by the combination of C-PCM and SMD. [ABSTRACT FROM AUTHOR]

Plasmonic semiconductor nanomaterials have been widely accepted as promising candidates for photothermal conversion, while the efficiency is yet to optimize. Herein, we report a facile synthesis of Au@Cu x O mesoporous nanospheres anchored with branched Ag nano-islands on the surface and explore their applications as photothermal conversion agent. Due to the intimate hybridization of two materials, the Au@Cu x O-Ag hybrid nanocomposites display a unique dual-plasmonic absorption that covers the visible-NIR range, benefiting the utilization efficiency of light energy. The synthesis is realized by reacting Au@Cu x O with Ag+, the galvanic replacement reaction between them enables a preferential depletion of Cu phase, leaving Ag and Cu 2 O as dominate crystal phases. The resulting hybrid nanocomposites are featured with a core-shell structure but incomplete coverage, as well as the mesoporous interior and dendritic outer shell. In addition to the enhanced photothermal conversion efficiency, the current nano-hybrids show excellent structural stability and no decay in conversion after five successive rounds of measurement. The advantages in both morphological and electronic structure aspects are discussed. The present study validates the promising synergetic use of distinct hot charge carriers originating from metal and semiconductor that are photoexcited in the same hybrid nanoparticle for photothermal conversion, shedding light on rational design of photothermal materials based on metal-semiconductor hybrid nanocomposites. Au@Cu x O mesoporous nanospheres anchored with branched Ag nano-islands are successfully prepared with dual plasmonic absorptions covering the vis-NIR region, exhibiting improved photothermal conversion efficiency and cycling stability. [Display omitted] [ABSTRACT FROM AUTHOR]

The deviations of gas phase enthalpy of formation predicted by density functional theory on the fluorine containing system are larger than those on other systems in most cases. Therefore, an enthalpy of formation test set composed of 41 organic fluorine containing compounds is proposed, and in this work it is called OFCC41 test set. Twenty exchange‐correlation functionals are estimated by CCSD(T)/CBS as benchmark. The first part of the results indicates that CAM‐B3LYP, ωB97X, and M06 are the most suitable functionals to predict enthalpies of formation for fluorine containing compounds. The remainder of this work is primarily concerned with diffuse basis sets and size‐dependent effects. Diffuse basis sets ma‐SVP and ma‐TZVP can generally improve the prediction performance. For very small molecules, using ma‐SVP is sufficient while for larger molecules more completed basis sets are demanded. Size‐dependent effect of prediction accuracy on different molecules is revealed by using a simple strategy, that the different sizes of molecules are distinguished with three intervals and given the corresponding mean absolute errors. This study provides a test set designed for organic fluorinated compounds and contributes to the selection of some functionals suitable for fluorine containing system. [ABSTRACT FROM AUTHOR]

[Display omitted] • A 2D/2D gC 3 N 4 /MoS 2 van der Waals heterojunction photocatalyst was prepared by a novel one-step method. • The type II band arrangement promotes an increase in photogenerated carrier concentration and separation of photogenerated charge carriers. • The in-situ formed heterojunction interface between gC 3 N 4 and MoS 2 boosts H 2 evolution by 3 times. Two-dimensional (2D) heterostructures have proven their efficiency in separating charges. Herein, a gC 3 N 4 /MoS 2 (CN/MoS 2) photocatalyst, in the form of 2D/2D van der Waals heterojunction with a type-II band alignment, was synthesized using a novel one-step method. The resulting in-situ formed heterojunction interface enhances electron transfer from gC 3 N 4 to MoS 2. The CN/MoS 2 photocatalyst exhibits exceptional activity in generating hydrogen from water under simulated solar light. Its hydrogen production rate was 1285 μmol/h/g, which was approximately 3 times higher compared to gC 3 N 4. This superiority is due to a significant increase in photogenerated carrier density and efficient charge separation facilitated by the type-II heterojunction. This study demonstrates a straightforward one-step approach for synthesizing 2D/2D composite photocatalysts, highlighting the effective synergy between different 2D materials in promoting hydrogen generation. [ABSTRACT FROM AUTHOR]

In this research, highly dispersed silica/water nanofluids of various particle sizes were successfully prepared using a facile one step sol–gel process. Nanofluids with particle sizes of 5 nm, 10 nm, 25 nm and 50 nm were confirmed by electron microscopy and light-scattering technique. The transmittance and thermal conductivity of the prepared nanofluids were measured. Our results showed that the transmittance of nanofluid with particle size of 5 nm and volume fraction of 2% can be as high as 97%, very close to pure water. Meanwhile, the thermal conductivity for this nanofluid showed ca. 20% enhancement. The good transmittance and high thermal conductivity of the prepared nanofluid enable us to de-couple the photovoltaic (PV) and thermal systems so that each can operate at an optimum temperature. In our design, the infrared part of the concentrated light, which cannot be converted to electricity by PV cell, was absorbed by nanofluid before arriving at PV cell surface. The additional heat generated by PV cell upon electivity generation could be removed by nanofluid flowing below it. The designed PV/T system was reduced to a 2-dimension (2D) physical model and numerically studied by CFD. This design is helpful to reduce the operation temperature of PV cell and thus is expected to improve its photoelectric efficiency. Exergetic efficiencies for PV/T model with various light concentrations versus the velocities of the nanofluid flow were investigated. When the concentration is 40 and the flow velocity is 0.015 m/s, the PV/T system has the highest exergetic efficiency and an enhancement of 7.0% exergetic efficiency was obtained by using nanofluid compared to using DI water. When the concentration is 100 and at the flow velocity of 0.1 m/s, an exergetic efficiency enhancement of 9.5% can be obtained. Considering the practical application of PV/T system, economic flow rate and low cost concentration are always favored. Concentration of 40 at flow velocity of 0.015 m/s was concluded to be the optimal operation parameters for our designed PV/T model using SiO 2 /water nanofluid (5 nm, 2 v%) as working fluid. [ABSTRACT FROM AUTHOR]

Controlled synthesis of two-dimensional noble metal nanomaterials with an in-plane branching morphology has been of great research interest recently, but has so far achieved limited success for AuAg-based nanocrystals. Herein, we report the fabrication of gold–silver (AuAg) nanosheets with abundant in-plane cracking and sub-10 nm thickness via one-pot kinetics-controlled synthesis. In particular, the dropwise addition of Au/Ag precursor solutions into a mixture of octadecyltrimethylammonium chloride and ascorbic acid, kept in an ice–water bath, leads to the formation of nanobelts/nanowires initially, followed by their growth into branched nanosheets. These AuAg products can further convert to AuAgM (M = Pd or Pt) nanosheets via galvanic replacement reaction under ambient conditions. Interestingly, the AuAgPd nanosheets are obtained with a Au@PdAg core–shell elemental distribution with many zigzag edges. In contrast, the AuAgPt nanosheets show a homogeneous distribution of all three metals, together with a highly stippled surface. All these AuAg-based nanosheets exhibit strong absorbance in the near-infrared region and thus show superb activities as photocatalysts for UV-vis light-assisted reduction of 4-nitrophenol due to the effect of plasmon enhancement. The present study provides a feasible route to generating AuAg-based multimetallic nanocrystals with a two-dimensional structure, in-plane branching morphology, and effective control over the elemental distribution, which could be potentially extended to other noble metals and/or alloys for the rational design of plasmonic photocatalysts. [ABSTRACT FROM AUTHOR]

Gold–palladium (AuPd) alloy nano-corolla are successfully prepared in high purity, followed by exploration as electrocatalysts for electroxidation of ethanol (EOR) in alkaline medium. Applying kinetics control on the one-pot formation process using a syringe pump is emphasized, where the Au/Pd precursor solution is dropwise titrated into the reaction mixture containing capping agent and reductant at an elevated temperature. We perform systematical investigation towards the morphology evolution pathway and effects of several key parameters. After loading on carbon black, the current AuPd alloy nano-corolla exhibit superb specific activity, reaction kinetics, and operation stability for EOR, showing morphological and structural merit. The present study provides insight into fabrication of bimetallic alloy nanocrystals with open structure, which could find important use in crystal engineering for multimetallic nanocrystals and rational design of fuel cell electrocatalyst. Gold–palladium (AuPd) alloy nanocrystals in the form of corolla are successfully prepared via kinetic-controlled synthesis in high purity, exhibit improved activity and stability as EOR electrocatalysts in KOH solution [ABSTRACT FROM AUTHOR]

Wavy gold@palladium-gold (Au@PdAu) core-shell nanoplates are successfully prepared via seeded growth. Starting with the use of plate-like Au nanocrystals with the thickness of ~10 nm as seeds, the preferential deposition of Pd atoms vertical to the upper/bottom surface plane allows the formation of the core-shell structure with tunable thickness, where the shell thickness can be limited to sub-10 nm. As confirmed by X-ray diffraction (XRD) analyses, further atomic diffusion allows the generation of PdAu alloy phase in the products, leading to the formation of Au@PdAu core-shell nanostructure. With the strong absorbance in near-infrared (NIR) region, they could work as efficient catalysts towards reduction of 4-nitrophenol under visible light irritation. In particular, the enhancement factor (the ratio of apparent rate constant in light to that in dark) reaches as high as 6.76 arising from the plasmonic-enhancement effect. The current work provides a feasible strategy to fabricate Pd-based bimetallic nanocrystals with plasmonic properties and validates their promising application in the plasmonic-enhanced catalysis. [ABSTRACT FROM AUTHOR]

Abstract: Na2Ti2O4(OH)2 nanotubes were obtained by hydrothermal reaction of TiO2 with concentrated NaOH solution. CdS nanoparticles were then decorated on Na2Ti2O4(OH)2 nanotubes through partial ion-exchange method. The composite photocatalysts were characterized by X-ray diffraction (XRD), ultraviolet–visible spectra (UV–vis), transmission electron microscope (TEM), etc. The results showed that CdS nanoparticles of 5–6nm were anchored on the surface of the Na2Ti2O4(OH)2 nanotubes. Under irradiation of visible light (λ ≥430nm), the prepared CdS/Na2Ti2O4(OH)2 showed high photoactivity for hydrogen production. [Copyright &y& Elsevier]

Summary: Little is known about the functional differences between the human skin myeloid dendritic cell (DC) subsets, epidermal CD207+ Langerhans cells (LCs) and dermal CD14+ DCs. We showed that CD14+ DCs primed CD4+ T cells into cells that induce naive B cells to switch isotype and become plasma cells. In contrast, LCs preferentially induced the differentiation of CD4+ T cells secreting T helper 2 (Th2) cell cytokines and were efficient at priming and crosspriming naive CD8+ T cells. A third DC population, CD14−CD207−CD1a+ DC, which resides in the dermis, could activate CD8+ T cells better than CD14+ DCs but less efficiently than LCs. Thus, the human skin displays three DC subsets, two of which, i.e., CD14+ DCs and LCs, display functional specializations, the preferential activation of humoral and cellular immunity, respectively. [Copyright &y& Elsevier]

Abstract: Ni2+ doped Cd1−x Zn x S microsphere photocatalysts were prepared by a new hydrothermal method. Experimental results showed that the doped Ni2+ can not only affect the crystal structure and morphology of Cd1−x Zn x S photocatalysts, but also greatly improve its photocatalytic activity. It was found that 0.1wt% Ni2+ doped Cd0.1Zn0.9S photocatalyst showed the highest activity with the apparent quantum yield of 15.9% at 420nm. The reason for the positive effects of Ni2+ was discussed. [Copyright &y& Elsevier]

Etching and regrowth are two typical processes involved during wet-chemical synthesis of noble-metal nanocrystals. In the present study, we demonstrate that by rationally manipulating the two processes, trimetallic nanocrystals with a unique multilayered structure can be successfully prepared in high purity, as well as with tunable sizes. In particular, by conducting co-reduction of Pd and Pt precursors in the presence of spherical Au seeds, the continuous etching of Pt(IV) ions as enabled by insufficient reducing power, together with the regrowth of Au and Pd atoms during the growth stage, allows the resultant products to exhibit a multi-layered elemental distribution, where Pd and Pt are in the inner shell while Au and Pt are dominant in the outer shell. When supported on carbon and used as electrocatalysts, these AuPdPt multilayered nanodendrites with controlled sizes in the range of 32–88 nm show an improved electrocatalytic activity and long-term durability for formic acid oxidation, as compared to commercial Pt/C. The present study offers a facile method to prepare tri-metallic nanocrystals with a controlled shape and spatial elemental distribution, which could be further extended to other noble metals or alloys. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Important progress has been made in the development of energetic molecules with high performance by computer‐aided molecular design in recent years, but structural novelty of organic scaffolds is insufficient. In this work, we propose an intra‐ring bridging strategy inspired by the known energetic nitramines to design novel polycyclic and cage energetic molecules. More than 100 energetic structures were designed by introducing the C—C bridges and increasing the ring size. The synthesis difficulty is considered besides the two most concerned properties of EMs, energy and safety. After a comprehensive estimation, a symmetric cage molecule labeled as 8U‐30 was finally selected because of its relatively high detonation performance, and comparable impact sensitivity as well as synthetic accessibility with CL‐20. Hopefully, the proposed strategy could be utilized in further molecular design to gain various scaffolds, especially cage structures, for different demands. [ABSTRACT FROM AUTHOR]

Strontium titanate (SrTiO3) is one of the most promising photocatalysts for overall water splitting (OWS). Strains can be commonly introduced in SrTiO3 during the synthetic processes, for example, in pulsed laser deposition. However, the effect of the strains on the catalytic performance of OWS is still unclear to date. Herein, first-principles calculations were performed to evaluate the impact of biaxial strains applied in SrTiO3 (001) surface on the oxygen evolution reaction (OER), the bottleneck of OWS. It was found that the applied strains, especially the compressive strains, significantly affect the free energy changes for H2O dissociation and *OOH deprotonation of OER on SrTiO3 (001). More interestingly, the tensile strains reduce the surface energy and lower the OER overpotential through reducing the free energy change for the rate-determining step, i.e., the second step of OER (*OH deprotonation), while the compressive strains increase the surface energy and the OER overpotential. Consequently, it is probable to introduce the tensile strains in the synthetic process to enhance the OER performance on SrTiO3 (001) surface. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis, in which solar energy drives CO2 to produce hydrocarbon fuels, is considered an effective way to solve the increasingly serious energy crisis and mitigate the greenhouse effect. Herein, layered porous Ru‐loaded and La‐doped g‐C3N4 nanosheets (Ru‐LGCNs) were prepared by one‐step calcination, followed by in situ photoreduction deposition of Ru. The layered Ru‐LGCN showed excellent photocatalytic CO2 reformation of methane performance under visible light, and the generation rates of CO, CH3CH3, CH3OH and CH3CH(OH)CH3 were 133, 154, 251 and 133 μmol h−1 g−1, respectively. The reason for the enhanced photocatalytic activity of Ru‐LGCN is the synergistic effect of bimetallic Ru and La. It is worth noting that the doped La can provide a good channel for charge transfer between LGCNs and CO2. This change in the charge behavior of the transport path is beneficial to break the C=O bonds on the active site La and generate methyl radicals on Ru, resulting in the generation of C2+ hydrocarbons. [ABSTRACT FROM AUTHOR]