A TiO2/GO composite with a Ti-O-C interfacial channel creates a delocalized electron pathway and built-in electric field, facilitating charge separation and lowering activation energy. T-GO-0.5 achieves CO evolution of 189.3 µmol g-1 h-1, further boosted to 234.0 µmol g-1 h-1 at 70 °C via the photothermal effect.

Space nuclear reactors are pivotal for advancing deep space exploration, with the closed Brayton cycle being the most suitable power conversion technology for megawatt-scale systems. Unlike terrestrial reactors, space systems face unique challenges in achieving high thermal efficiency while minimizing mass and costs to ensure orbital launch feasibility. This study focuses on designing a Space Nuclear Energy Reactor system (SNER), evaluating its thermodynamic performance, mass characteristics, and economic implications. Key parameters such as turbine and compressor inlet temperatures, compressor pressure ratio, and recuperator efficiency were analyzed, revealing interdependence among system efficiency, specific mass, and levelized energy cost. Through multiobjective optimization, the theoretical performance limits of the SNER were established. The optimized configuration, compatible with Chinese and American heavy lift launch vehicles for geostationary transfer orbit (GTO), achieves a thermal efficiency of 40.64%, a specific mass of 11.67 t/MWe, and a levelized energy cost of 0.091 $/kWh. Notably, the radiator accounts for over 44% of the system mass, highlighting its importance in mass reduction efforts. This research provides valuable insights for the conceptual design and optimization of space nuclear reactor systems, offering both theoretical and practical significance for future advancements.

Natural chalcopyrite CuFeS2 is a promising sulfide electrode for lithium-ion batteries, yet its multiscale structural and chemical evolution during cycling remains insufficiently understood. Here, synchrotron X-ray absorption spectroscopy, Raman spectroscopy, operando synchrotron computed tomography (CT), molecular dynamics (MD), and density functional theory are combined to clarify its lithiation mechanism and stability origin. During the first discharge, CuFeS2 undergoes stepwise conversion: Li+ intercalation first induces amorphization, Cu extrusion, and formation of amorphous Li2FeS2, followed by further decomposition into amorphous Fe and Li2S. Thermodynamic calculations show that the amorphous pathway is more favorable than the crystalline route, confirming reaction-induced amorphization. Upon charging, amorphous Fe is re-sulfurized to form amorphous FeS2 with S2 2- dimers, whereas Cu remains irreversibly metallized. Subsequent cycles follow a lower-energy Fe/FeS2 redox pathway, which prevents chalcopyrite reconstruction. Operando CT and impedance analysis reveal that, despite severe particle fragmentation, the retained metallic Cu network maintains electronic transport, while the absence of soluble polysulfides suppresses parasitic reactions. These findings explain the cycling stability of natural chalcopyrite electrodes and guide the design of durable sulfide-based materials.

To investigate the unsteady aerodynamic characteristics of rotor with Variable Trailing-Edge Camber (VTEC), an unsteady rotor flowfield simulation method is established based on the URANS equation by introducing a deformable moving-embedded grid method. The influence mechanisms of variable-camber amplitude Am, frequency k, and phase φ0 on the unsteady aerodynamic characteristics of rotor are analyzed thoroughly, and whereby a VTEC optimization method is proposed through cross-iteration of variable-camber parameters to achieve the dual objectives of hub load suppression and trim maintenance. The numerical experiments indicate that the k=3 harmonic plays a dominant role in controlling the fluctuation of vertical hub load, which corresponds to the three-bladed rotor. The feasibility of dual load suppression/trim maintenance of VTEC is demonstrated, in which the fluctuation amplitudes of hub loads increments exhibit quasi-linear relationships with Am for k=0-4 and the fluctuation phase of vertical hub load variation shifts synchronously with the adjustment of φ0 for k=2-4. The results demonstrate that the proposed load suppression method can effectively decrease the fundamental 3/rev vertical hub load and simultaneously maintain the rotor trim state.

Solar-driven dry reforming of methane (DRM) presents a sustainable path to close the carbon cycle but suffers from low solar-fuel efficiency and coke-induced instability. Here, we propose the synergy of plasmonic meta-nanoalloy catalysts with butterfly wing-inspired foam reactors to achieve ordered, scalable solar-driven DRM. Developed NiCoZn/MgAlOx catalysts exhibit a benchmark solar-fuel efficiency of 42.4%, a high H2/CO ratio of 0.95, and a CO2 conversion rate that surpasses thermodynamic equilibrium values. The underlying mechanism is attributed to plasmonic activation of the initial C-H bonding of CH4 and C-O bonding of CO2 while suppressing complete methane cracking, steering the reaction toward an ordered pathway (*CH + *O = *CHO) instead of disordered route (*CH = *C + *H). Further depositing plasmonic catalysts on biomimetic dual-gradient foam reactors enables the synergy of plasmonic catalysis with light transport, reactants flow, and fluid-solid energy exchange. A bench-scale solar-driven DRM system demonstrates a remarkable solar-fuel efficiency of 41.11% and durable performance of nearly 10,000 min.

Research into cuprous oxide (Cu2O) is continually expanding. This traditional antifouling material is now being widely applied as a photocatalytic nanomaterial. This review comprehensively summarizes recent breakthroughs in Cu2O photocatalytic nanomaterials, focusing on their antifouling mechanisms and expanding applications. The main contents include: preparation technology innovations, antifouling mechanism analyses, performance optimization strategies, and application scenario expansion. Firstly, it overviews advanced preparation methods such as liquid-phase reduction, hydrothermal synthesis, and electrochemical deposition, along with regulatory effects on the microstructure, particle size, crystal facets, and crystalline structure of Cu2O. Secondly, the multiple antibacterial mechanisms of Cu2O were revealed from three dimensions: copper ion release-mediated biocidal action, reactive oxygen species (ROS) generation and cell membrane destruction. Subsequently, the optimization strategies for the antifouling performance of Cu2O materials through interface matching regulation by nanomaterials of different dimensions were reviewed. Fourth, this review thoroughly analyzes application prospects of Cu2O in diverse scenarios, including ship maintenance, sensing technology, water purification, and aquaculture. Finally, future development prospects are outlined. Based on the existing technical bottlenecks, this review proposes that Cu2O will develop in the direction of intelligence, environmental protection and high efficiency in the future.

Efficient, stable, low costs and environmentally friendly electrocatalysts are crucial for hydrogen evolution reactions. Multi-dimensional porous coatings containing NiO2/Ni2O3 heterostructures were fabricated by laser spraying through regulating spray distance. The surface morphology, oxygen content and microstructures of the coatings were characterized. The electrochemical performance of the coatings was evaluated and the density functional theory (DFT) calculations were employed to explore the electrocatalytic mechanism. The results indicate that increasing the spray distance benefited the formation of multi-dimensional porous coatings. The bonding mechanism of the coatings involved metallurgical bonding and mechanical interlocking. The oxygen content of the coatings increased as the spraying distance increased, and the NiO2/Ni2O3 heterostructure was found due to the rapid solidification of the melted particles. Specifically, the catalytic electrode with the NiO2/Ni2O3 heterostructure exhibited better performance. The charge density difference from DFT calculations indicates electron transfer at the interface of the NiO2/Ni2O3 heterostructure. Furthermore, the NiO2/Ni2O3 heterostructure exhibited higher density of states and lower Gibbs free energy compared to the individual NiO2 and Ni2O3 structures, which benefited the enhancement of hydrogen adsorption and reaction rates. This work provides a new technology for hydrogen production catalysts with the advantages of porous structures, low costs and simple operation.

Solar spectral conversion using fluorophores offers a promising way to tailor solar light for photo-fermentative hydrogen production (PFHP). This study aimed to improve light conversion efficiency for photo-fermentative hydrogen production from giant reed by precisely matching the absorption peak of photosynthetic bacteria to the solar spectrum. Seven color fluorophores with different emission wavelengths (λem) were manufactured into solar spectral converters to evaluate the effects on cell growth and biohydrogen production. All converters could shift UV to visible light. The converter with λem = 482 nm significantly (p < 0.05) increased the photosynthetic rate (PR) by 91 % during cell growth process, while the converters with λem = 596 nm and λem = 603 nm enhanced hydrogen yield by 37 % and 35 %, respectively. Moreover, the converter with λem = 596 nm enhanced the light conversion efficiency (LCE) by 34 % and the nitrogenase activity by 144 %. This study provides a new sight for further enhanced outdoor biohydrogen production driving by solar energy.

The chemical inertness of CO2 molecules makes their adsorption and activation on a catalyst surface one of the key challenges in recycling CO2 into chemical fuels. However, the traditional template synthesis and chemical modification strategies used to tackle this problem face severe structural collapse and modifier deactivation issues during the often-needed post-processing procedure. Herein, a CO2 self-selective hydrothermal growth strategy is proposed for the synthesis of CeO2 octahedral nanocrystals that participate in strong physicochemical interactions with CO2 molecules. The intense affinity for CO2 molecules persists during successive high-temperature treatments required for Ni deposition. This demonstrates the excellent structural heredity of the CO2 self-selective CeO2 nanocrystals, which leads to an outstanding photothermal CH4 productivity exceeding 9 mmol h(-1) m(cat)(-2) and an impressive selectivity of >99%. The excellent performance is correlated with the abundant oxygen vacancies and hydroxyl species on the CeO2 surface, which create many frustrated Lewis-pair active sites, and the strong interaction between Ni and CeO2 that promotes the dissociation of H-2 molecules and the spillover of H atoms, thereby greatly benefitting the photothermal CO2 methanation reaction. This self-selective hydrothermal growth strategy represents a new pathway for the development of effective catalysts for targeted chemical reactions.

Numerous studies have focused on efficient CO2 photoreduction on short notice. However, more hours of efficient and selective CO2 and pure water photoconversion without precious metals or sacrificing reagents should be emphasized. Herein, a multilayer (SrTiO3/Ce:CaF2/CuNi/Ce:CaF2/TiN) is utilized with a high selectivity of 87 % for healable photocatalytic CO2 and pure water conversion without sacrificial reagents and the longest service life for the Cu nanolayers, to the best of our knowledge. Meanwhile, the photocatalytic activity, optical absorption, and charge separation ability of SrTiO3/Ce:CaF2/CuNi/Ce:CaF2/TiN can be recovered after regeneration. The deactivation and healable mechanism are illuminated that the adsorption of CO2 molecules at the photocatalyst surface is changed from M-CO2 to MO-CO2, due to the oxidation of active sites, resulting in the deactivation of CO2 reduction. The Ce:CaF2 nanolayers can accommodate oxygen atoms effectively to heal the photocatalyst. The article proposes a feasible way for commercial CO2 and pure water photoconversion.

Photoelectrocatalytic (PEC) reduction of nitrobenzene (NB) is an extremely promising technology for renewable energy utilization and conversion. PEC reduction of NB to produce higher-value azobenzene (AZB) instead of aniline (AN), which is now commonly reported, is not currently achievable. In this work, we fabricated Ag nanoparticles (AgNPs)-decorated silicon nanocone (SiNC) array photocathodes with which the PEC reduction of NB to azobenzene (AZB) was realized for the first time. The SiNC array structure constructed by cryogenic dry etching greatly improved the light absorption ability of the photoelectrode. Ag was chosen as the cocatalyst because of its larger potential difference for the NB reduction reaction and the competing side reaction hydrogen evolution reaction. The Schottky junction formed by AgNPs with Si facilitates the rapid extraction of photogenerated electrons to participate in the PEC reaction. Under the optimized conditions, the PEC reduction of NB was achieved with a conversion of more than 90 %, with the reduction products being mainly AZB (9 : 1 ratio of AZB to AN) as well as excellent stability. The present work provides a photoelectrode that highly selectively PEC reduction of NB to AZB, and also provides insights into the design and preparation of high-performance silicon-based photoelectrodes. A silicon nanocone (SiNC) arrays photocathode decorated with silver nanoparticles (AgNPs) was fabricated and applied to photoelectrocatalytic (PEC) nitrobenzene reduction reaction (NBRR). The SiNC arrays endow the photocathode with excellent anti-light reflection performance. And the photocathode exhibits superior stability, outstanding nitrobenzene reduction activity and AZB selectivity. image

In a recent issue of Cell Reports Physical Science, Bent and co-workers studied the electrochemical conversion of four typical nickel-based precatalysts toward alkaline oxygen evolution reaction and the effect of iron impurities on their conversion and catalytic activity. This is undoubtedly a key guide for designing alkaline oxygen evolution precatalysts.

The thermochromic effect of modified VO2 enhances photocatalytic CO2 reduction, and its dynamic change process is monitored by a series of in situ experimental verifications and theoretical calculations.

The using of reductive cocatalysts to dictate the transfer path of electrons towards targeting products is indispensable for photocatalytic CO2 reduction reaction (CRR). However, the development of low-cost and highly selective cocatalysts for photocatalytic CRR remains a daunting challenge. Herein, a functional molecule decoration strategy is proposed to tune the surface electronic structures of semiconductor photocatalysts, in order to promote their photocatalytic performance in CRR. We employ cyanamide groups as the chemical modifiers to regulate the CRR performance of solid solution metal sulphide photocatalysts. The synthesized photocatalysts exhibit excellent photocatalytic performance in CRR, and the highest CO evolution rate exceeds 1400 mu mol g(-1)h(-1), being among the best results reported to date. Multiple characterizations in combination with theoretical simulations further demonstrate that the decorated cyanamides do not act as active sites, but changes the electronic structures of the neighboring surface lattice metal atoms and decreases the kinetic barrier of the rate determining *CO2 ->*COOH step, thereby making the surface much more active for photocatalytic CRR. These findings explicitly verify the effectiveness of the functional molecule decoration strategy in promoting the CRR performance of photocatalysts, and also open up a new pathway for the development of highly efficient and selective catalysts for specific catalytic reactions.

Improving the water-splitting performance of hematite (a-Fe2O3) is still hindered due to its severe charge recombination and poor water oxidation kinetics. Herein, borate-treated Ti -Fe2O3 combined with a FexNi1-xOOH cocatalyst (FexNi1-xOOH/B/Ti-Fe2O3) greatly improved the performance of Ti-Fe2O3, and reached a notable photocurrent density of 3.39 mA/cm2 at 1.23 V vs. RHE. Transient surface photovoltage spectroscopy (TPV) directly reveals that [B(OH)4]- as a Lewis base can selectively passivate acceptor surface states on Ti -Fe2O3 photoanode surface, efficiently enhancing the charge separation efficiency. Moreover, the FexNi1-xOOH thin layer is devoted to further facilitate holes injection into the electrolyte, accelerating the water oxidation kinetics of Ti-Fe2O3 photoanode. The synergetic integration of acceptor surface states passivation and FexNi1-xOOH cocatalyst provides a novel strategy for the construction of efficient photoanodes by surface engineering. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Atomically dispersed NiO 6 clusters decorated on sulphide photocatalysts effectively activate the surface lattice atoms of sulphide semiconductors, resulting in a remarkable improvement in hydrogen production at a loading amount as low as 0.05 wt%.

The photocatalytic conversion of CO2 to fuel and valuable carbon compounds is a feasible method for the large-scale reuse of CO2. However, it involves complex multi-processes and physical phenomena, limiting the enhanced performance of photocatalysis. Consequently, building a comprehensive model is necessary. Herein, we present a multi-process computational framework for simulating the whole photocatalytic CO2 reduction process. In this work, the physical and chemical properties of the catalysts were determined by density functional theory (DFT). Specifically, we employed a framework consisting of an optical absorption and carrier transport model to simulate the conversion process from photons to carriers, a micro-kinetic model to describe the surface catalytic reaction process, and a continuum transport model to calculate the mass transfer process between the solution and surface. Using this multiscale model, we simulated and analyzed the photocatalytic processes of rGO-MoS2/PPy (MoS2 and polymer polypyrrole on reduced graphene oxide). The simulation clarified the key factors affecting the catalyst activity and selectivity. Moreover, the energy loss in different processes was also clarified, which showed that the model can be a theoretical analysis tool for analyzing and improving the photocatalytic performance of materials.

随着无人机数量的增长,无人机间飞行冲突的自动解脱研究成为热点.针对冲突无人机数量变化的多机冲突解脱问题,采用一个集中式的深度多智能体强化学习算法——BiCNet算法.BiCNet算法包含参数共享机制和双向循环神经网络,使得冲突解脱模型可以支持动态扩展,即能够使用不同数量UAV的多机冲突场景进行训练,并理论上可以解脱任意数量冲突无人机的多机冲突,进而提高冲突解脱模型的训练效率.此外,基于微软面向无人机的开源仿真环境AirSim,设计了大量高密度的无人机多机冲突场景,并对冲突解脱模型进行了训练和测试.从实验的结果来看,训练曲线和测试结果表明解脱模型在求解时间和解脱率方面有很好的表现.

CuGaS2(CGS) is effectively synthesized by a one-step solid-phase sintering method. The conduction band maximum, valence band maximum and flat band potential of the obtained CGS are -1.14, 1.21 and 0.33 V vs RHE, respectively. When the Cu to Ga atom ratio is 1: 1.4 in the raw material, the prepared CuGaS2 exhibits the highest visible-light (lambda.420 nm) H-2 production activity. The hydrogen production rate of CuGaS2 reaches 1.12 mmol g(-1) h(-1) under visible-light radiation. When Ruthenium is loaded as cocatalyst, the H-2 production rate of CuGaS2@Ru is promoted to 3.38 mmol g(-1) h(-1). At the same, the interior component of photo-induced carries transfer among photoharvestor and cocatalyst has been revealed. This research provides a facile strategy to fabricate CuGaS2 with excellent photocatalytic performance for H-2 production. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

ZnS-CuInS2 (CIZS) solid solution is synthesized via a chitosan gel-assisted method. The bandgap of the obtained CIZS semiconductor is 1.68 eV, and the position of the flat potential is 0.86 eV. When Ru is selected as the cocatalyst, the photocatalytic hydrogen evolution rate of CIZS@Ru reaches 4.86 mmol g- 1h- 1 under visible-light (lambda>420 nm) radiation, and it presents good stability. Besides, CIZS@Ru also shows good CO2 reducibility, where the product contains hydrogen, methane, and a small amount of formate. The photoelectrochemical tests also suggest that Ru is the optimum cocatalyst compared with Rh, Pt and Ni. Meanwhile, the internal mechanism of photogenerated charge transfer between semiconductors and cocatalyst has been revealed by the band bending concept. This work provides a novel and facile strategy to fabricate p-type CIZS semiconductor with high visiblelight photocatalytic reduction performance.