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A DFT study on Pt single atom loaded COF for efficient photocatalytic CO_(2)reduction

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Journal of Materials Science & Technology 2024年第3期170卷 87-94页

作者： Fei Xie Chuanbiao Bie Jian Sun zhenyi zhang Bicheng Zhu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430078China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian116600China

Photocatalytic CO_(2)reduction provides a promising strategy for the alleviation of greenhouse effect and energy shortage problem.Metal single atom modification is an effective method to improve the CO_(2)reduction performance of covalent organic framework(COF)photocatalysts,while the intrinsic mechanism is not revealed in depth.Herein,a Pt-COF photocatalytic system was constructed by embedding Pt single atom in TFPT-TMT-COF(TFPT:1,3,5-tris(4-formylphenyl)-triazine,TMT:2,4,6-trimethyl-1,3,5-triazine).Based on density functional theory(DFT)calculation,the geometric structure and electronic property of Pt-COF were investigated,and the CO_(2)adsorption and reduction reaction process on Pt-COF were simulated.The results show that the Pt atom can be steadily anchored in COF via the formation of Pt-N and Pt-C bonds.Moreover,there is strong electronic interaction between Pt and COF.The incorporation of Pt atom benefits the CO_(2)reduction activity of COF from multiple aspects:(ⅰ)reducing the band gap and improving light absorption;(ⅱ)enhancing CO_(2)adsorption and activating the CO_(2)molecule;(ⅲ)decreasing the energy barrier in the hydrogenation step of CO_(2)→COOH,thus facilitating CO_(2)conversion to CO;(ⅳ)inhibiting the hydrogenation of CO,thereby increasing the selectivity of CO.This work brings a novel insight into the excellent CO_(2)reduction performance of Pt modified COF,and provides useful references for the design of single atom photocatalysts.

关键词： Photocatalysis Carbon dioxide reduction Covalent organic framework Pt single atom Theoretical calculation

Recent progress in CdS-based S-scheme photocatalysts

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Journal of Materials Science & Technology 2024年第4期171卷 162-184页

作者： Yajing Ren Yunfeng Li Guixu Pan Ning Wang Yan Xing zhenyi zhang College of Environmental and Chemical Engineering Xi’an Polytechnic UniversityXi’an 710048China Jilin Provincial Key Laboratory of Advanced Energy Materials Department of ChemistryNortheast Normal UniversityChangchun 130024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Photocatalytic technology with sunlight as driving force can convert solar energy into other energy sources for storage and further use.Cadmium sulfide(CdS),as a typical reducing semiconductor of metal sulfides,represents an interesting research hotspot in photocatalysis due to its suitable bandgap(2.4 eV)for utilizing visible light and strong reducing ability for inducing surface catalytic reactions.Unfortunately,the photocatalytic performance of CdS is still limited by its fast carrier recombination and serious pho-tocorrosion.So far,CdS semiconductor has been widely developed as a typical reducing photocatalyst in constructing novel S-scheme heterojunction to overcome the above drawbacks.In this review,the de-sign concepts,basic principles,and charge transfer characteristics of CdS-based S-scheme heterojunction photocatalysts have been comprehensively introduced.Several advanced and effective characterization methods for studying the mechanism of CdS-based S-scheme heterojunction are analyzed in detail.Fur-thermore,we also summarize the typical applications of CdS-based S-scheme heterojunctions for water splitting,CO_(2) reduction,pollutant degradation,etc.Eventually,according to the current investigation sta-tus,some drawbacks in the current synthetic strategy,mechanism exploration,and application prospect of CdS-based S-scheme heterojunction are proposed,which need to be addressed by further expansion and innovative research.

关键词： Photocatalysis CdS semiconductor Heterojunction S-scheme Metal sulfide

Behavioral control task supervisor with memory based on reinforcement learning for human-multi-robot coordination systems

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Frontiers of Information Technology & Electronic Engineering 2022年第8期23卷 1174-1188页

作者： Jie HUANG Zhibin MO zhenyi zhang Yutao CHEN School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China G+Industrial Internet Institute Fuzhou UniversityFuzhou 350108China Key Laboratory of Industrial Automation Control Technology and Information Processing of Fujian Province Fuzhou UniversityFuzhou 350108China

In this study,a novel reinforcement learning task supervisor(RLTS)with memory in a behavioral control framework is proposed for human–multi-robot coordination systems(HMRCSs).Existing HMRCSs suffer from high decision-making time cost and large task tracking errors caused by repeated human intervention,which restricts the autonomy of multi-robot systems(MRSs).Moreover,existing task supervisors in the null-space-based behavioral control(NSBC)framework need to formulate many priority-switching rules manually,which makes it difficult to realize an optimal behavioral priority adjustment strategy in the case of multiple robots and multiple tasks.The proposed RLTS with memory provides a detailed integration of the deep Q-network(DQN)and long short-term memory(LSTM)knowledge base within the NSBC framework,to achieve an optimal behavioral priority adjustment strategy in the presence of task conflict and to reduce the frequency of human intervention.Specifically,the proposed RLTS with memory begins by memorizing human intervention history when the robot systems are not confident in emergencies,and then reloads the history information when encountering the same situation that has been tackled by humans previously.Simulation results demonstrate the effectiveness of the proposed RLTS.Finally,an experiment using a group of mobile robots subject to external noise and disturbances validates the effectiveness of the proposed RLTS with memory in uncertain real-world environments.

关键词： Human-multi-robot coordination systems Null-space-based behavioral control Task supervisor Reinforcement learning Knowledge base

Reinforcement Learning Behavioral Control for Nonlinear Autonomous System

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IEEE/CAA Journal of Automatica Sinica 2022年第9期9卷 1561-1573页

作者： zhenyi zhang Zhibin Mo Yutao Chen Jie Huang the College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108 the Key Laboratory of Industrial Automation Control Technology and Information Processing Education Department of Fujian ProvinceFuzhou 350108 G+Industrial Internet Institute Fuzhou UniversityFuzhou 350108China

Behavior-based autonomous systems rely on human intelligence to resolve multi-mission conflicts by designing mission priority rules and nonlinear controllers.In this work,a novel twolayer reinforcement learning behavioral control(RLBC)method is proposed to reduce such dependence by trial-and-error learning.Specifically,in the upper layer,a reinforcement learning mission supervisor(RLMS)is designed to learn the optimal mission priority.Compared with existing mission supervisors,the RLMS improves the dynamic performance of mission priority adjustment by maximizing cumulative rewards and reducing hardware storage demand when using neural networks.In the lower layer,a reinforcement learning controller(RLC)is designed to learn the optimal control policy.Compared with existing behavioral controllers,the RLC reduces the control cost of mission priority adjustment by balancing control performance and consumption.All error signals are proved to be semi-globally uniformly ultimately bounded(SGUUB).Simulation results show that the number of mission priority adjustment and the control cost are significantly reduced compared to some existing mission supervisors and behavioral controllers,respectively.

关键词： Behavioral control mission supervisor nonlinear autonomous system reinforcement learning

Electrospun Semiconductor-Based Nano-Heterostructures for Photocatalytic Energy Conversion and Environmental Remediation:Opportunities and Challenges

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Energy & Environmental Materials 2023年第2期6卷 212-238页

作者： Na Lu Mingyi zhang Xuedong Jing Peng zhang Yongan Zhu zhenyi zhang Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 45001China

Harvesting solar energy to drive the semiconductor photocatalysis offers a promising tactic to address ever-growing challenges of both energy shortage and environmental pollution.Design and synthesis of nano-heterostructure photocatalysts with controllable components and morphologies are the key factors for achieving highly efficient photocatalytic processes.Onedimensional(1D)semiconductor nanofibers produced by electrospinning possess a large ratio of length to diameter,high ratio of surface to volume,small grain sizes,and high porosity,which are ideally suited for photocatalytic reactions from the viewpoint of structure advantage.After the secondary treatment of these nanofibers through the solvothermal,gas reduction,in situ doping,or assembly methods,the multi-component nanofibers with hierarchical nano-heterostructures can be obtained to further enhance their light absorption and charge carrier separation during the photocatalytic processes.In recent years,the electrospun semiconductorbased nano-heterostructures have become a“hot topic”in the fields of photocatalytic energy conversion and environmental remediation.This review article summarizes the recent progress in electrospinning synthesis of various kinds of high-performance semiconductor-based nano-heterostructure photocatalysts for H2 production,CO_(2) reduction,and decomposition of pollutants.The future perspectives of these materials are also discussed.

关键词： electrospun nanofibers energy conversion environmental remediation photocatalysis semiconductor heterojunction

Regulating the dopant clustering in LiZnAs-based diluted magnetic semiconductor

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Chinese Physics B 2024年第5期33卷 617-623页

作者：贾子航周波姜振益张小东 Institute of Modern Physics Northwest UniversityXi'an 710069China Shaanxi Key Laboratory for Theoretical Physics Frontiers Northwest UniversityXi'an 710069China Department of Physics Chinese University of Hong KongHong Kong SARChina Beijing Computational Science Research Center Beijing 100193China

Tuning of the magnetic interaction plays the vital role in reducing the clustering of magnetic dopant in diluted magnetic semiconductors(DMS).Due to the not well understood magnetic mechanism and the interplay between different magnetic mechanisms,no efficient and universal tuning strategy is proposed at present.Here,the magnetic interactions and formation energies of isovalent-doped(Mn) and aliovalent(Cr)-doped LiZnAs are studied based on density functional theory(DFT).It is found that the dopant–dopant distance-dependent magnetic interaction is highly sensitive to the carrier concentration and carrier type and can only be explained by the interplay between two magnetic mechanisms,i.e.,superexchange and Zener’s p–d exchange model.Thus,the magnetic behavior and clustering of magnetic dopant can be tuned by the interplay between two magnetic mechanisms.The insensitivity of the tuning effect to U parameter suggests that our strategy could be universal to other DMS.

关键词： diluted magnetic semiconductor dopant distribution first-principles calculations

Sulfonate-Functionalized Polyoxovanadate-Based Metal-Organic Polyhedra for Enhanced Proton Conduction via the Synergy of Linker and Metal Cluster Vertex

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Chinese Journal of Structural Chemistry 2022年第8期41卷 12-17页

作者： Yu zhang Shan-Shan Liu Bo Li Hanqi You Longxi zhang zhenyi zhang Hong-Ying Zang Qi Zheng Weimin Xuan College of Chemistry Chemical Engineering and Biotechnology&State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsDonghua UniversityShanghai 201620China Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education at Universities of Jilin Province Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Bruker(Beijing)Scientific Technology Co. Ltd 9FBuilding No.1Lane 2570Hechuan RdMinhang DistrictShanghai 200233China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Metal-organic polyhedra(MOPs)have emerged as novel porous platforms for proton conduction,however,the concerted employment of both linker and metal cluster vertex is rarely applied for the fabrication of MOPs-based high conducting materials.Herein we report the synthesis of sulfonate-functionalized polyoxovanadate-based MOPs for enhanced proton conduction via the synergistic effect from linker and metal cluster node.MOPs 1 and 2 exhibit octahedral cage configuration constructed from{V_(5)O_(9)Cl}vertex and 5-sulfoisophthalate linker.Owing to the ordered packing of octahedral cages along three axes,3D interpenetrated open channels that are lined with high-density sulfonates are thus formed within 2.Coupled with the proton-conductive{V_(5)O_(9)Cl}vertexs as well as protonated counterions,an extensive H-bonded network is therefore generated for facile proton transfer.2 exhibits high proton conductivity of 3.02×10^(-2)S cm^(-1)at 65℃under 90%RH,recording the highest value for MOPs pellet sample.This value is enhanced~1order of magnitude compared with that of carboxylate-functionalized analogue 3,clearly illustrating the advantage of combining linker and metal cluster node for enhanced proton conduction.This work will further promote the exploitation of high proton conductive MOPs-based materials by the synergy design strategy.

关键词： metal-organic polyhedra proton conduction polyoxovanadate synergistic effect

基于行为的多差速机器人强化学习任务监管器设计

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机器人 2024年第4期46卷 397-413,424页

作者：张祯毅黄捷福州大学电气工程与自动化学院福建福州350108 福州大学5G+工业互联网研究院福建福州350108

针对多差速机器人系统提出了一种基于试错学习的多智能体强化学习任务监管器。此方法解决了基于行为的多智能体系统总是依赖人的智能设计切换规则以决策行为优先级的问题。首先,在零空间行为控制框架下引入了差速模型代替质点模型,首次... 详细信息

针对多差速机器人系统提出了一种基于试错学习的多智能体强化学习任务监管器。此方法解决了基于行为的多智能体系统总是依赖人的智能设计切换规则以决策行为优先级的问题。首先,在零空间行为控制框架下引入了差速模型代替质点模型,首次推导了具有非完整约束的零空间行为控制范式,从而提升了系统对最小极值状态的鲁棒性。然后,首次将行为优先级切换问题建模为协作式马尔可夫博弈问题,学习了一个最优的联合策略以动态且智能地决策行为优先级,不仅避免了人工设计切换规则,而且降低了在线计算和存储负担。仿真结果显示,所提出多智能体强化学习任务监管器具有优越的行为优先级切换性能。在AgileX Limo系列多差速机器人系统上的成功应用,验证了该任务监管器的实用性。

关键词：差速机器人行为控制强化学习任务监管器智能决策

A likely paleo-autotetraploidization event shaped the high conservation of Nyssaceae genome

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Horticultural Plant Journal 2024年第3期10卷 911-930页

作者： Yishan Feng zhenyi Wang Qimeng Xiao Jia Teng Jianyu Wang Zijian Yu Jiaqi Wang Qiang Xu Yan zhang Shaoqi Shen Shoutong Bao Yu Li Zimo Yan Yue Ding Zihan Liu Yuxian Li Tianyu Lei Min Yuan Xiu-Qing Li Jinpeng Wang Department of Bioinformatics School of Life SciencesNorth China University of Science and TechnologyTangshanHebei 063000China Fredericton Research and Development Centre Agriculture and Agri-Food CanadaFrederictonNew Brunswick E3B 4Z7Canada State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of ScienceBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

Scientific knowledge about the ancestral genome of core eudicot plant kingdom can potentially have profound impacts on both basic and applied research,including evolution,genetics,genomics,ecology,agriculture,forestry,and global climate.To investigate which plant conserves best the core eudicots common ancestor genome,we compared Arcto-Tertiary relict Nyssaceae and 30 other eudicot plant families.The genomes of Davidia involucrata(a known living fossil),Camptotheca acuminata and Nyssa sinensis,one per existent genus of Nyssaceae,were performed comparative genomic analysis.We found that Nyssaceae originated from a single Nyssaceae common tetraploidization event(NCT)-autotetraploidization 28-31 Mya after the core eudicot common hexaploidization(ECH).We identified Nyssaceae orthologous and paralogous genes,determined its chromosomal evolutionary trajectory,and reconstructed the Nyssaceae most recent ancestor genome.D.involucrata genome contained the entire seven paleochromosomes and 17 ECH-generated eudicot common ancestor chromosomes and was the slowest in mutation among the analyzed 42 species of 31 plant families.Combing both its high retention of paleochromosomes and its low mutation rate,D.involucrata provides the best case in conservation of the core eudicot paleogenome.

关键词： Nyssaceae Polyploidization Multigenome alignment Evolutionary rate Autotetraploidization Karyotype evolution