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Conversion-type cathode materials for high energy density solid-state lithium batteries

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Journal of Energy Chemistry 2025年第1期100卷 409-425页

作者： yuhao Ma Shihong Qing Hongyu Liu Chuntao Ma Yuan Yu Chuang Yu Liping Wang School of Materials and Energy University of Electronic Science and Technology of China Zhejiang Provincial Key Laboratory of Fiber Materials and Manufacturing Technology Zhejiang Sci-Tech University State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology

Solid-state lithium batteries （SSLBs） are regarded as an essential growth path in energy storage systems due to their excellent safety and high energy *** particular,SSLBs using conversion-type cathode materials have received widespread attention because of their high theoretical energy densities,low cost,and *** the great progress in research and development of SSLBs based on conversiontype cathodes,their practical applications still face challenges such as blocked ionic-electronic migration pathways,huge volume change,interfacial incompatibility,and expensive processing *** review focuses on the advantages and critical issues of coupling conversion-type cathodes with solid-state electrolytes （SSEs）,as well as state-of-the-art progress in various promising cathodes （e.g.,FeS2,CuS,FeF3,FeF2,and S） in ***,representative research on conversion-type solid-state full cells is discussed to offer enlightenment for their practical ***,the energy density exhibited by the S cathode stands out impressively,while sulfide SSEs and halide SSEs have demonstrated immense potential for coupling with conversion-type ***,perspectives on conversion-type cathodes are provided at the material,interface,composite electrode,and battery levels,with a view to accelerating the development of conversion-type cathodes for high-energy–density SSLBs.

关键词： Sulfur compounds

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： yuhao Peng Yuefeng Song Ihar Razanau Juanxiu Xiao Wei Xiao Di Hu Guoxiong Wang College of Chemistry and molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

Spatiotemporal evolution of Ediacaran-Cambrian(ca. 551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年

作者： Yan YE Lei ZHANG Can CHEN Shan CHANG yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Wuhan) School of Earth Science China University of Geosciences(Wuhan) Department of Geology Lund University Institute of Sedimentary Geology Chengdu University of Technology Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of Technology Second Geological Brigade of Hubei Geological Bureau College of Urban and Environmental Sciences Hubei Normal University Exploration and Development Research Institute SINOPEC Jianghan Oilfield Company

The origin and evolution of sponges have attracted interest, not only because they are among the most basal metazoans, but also because they act as important ecological engineers in the ocean. Previous research suggested that sponge groups diversified quickly during the Cambrian Series 2, while Terreneuvian sponge fossils are conspicuously rare and poorly substantiated. Yet, an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C, ca.551–523 Ma) transitional carbonates/cherts worldwide, particularly in South China, which calls for updated discussions. Ocean oxygenation has been widely proposed to play a critical role in organismal evolution, but its relationship with sponges is unclear and falls into a “chicken-egg” dilemma. In this study, we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous sponges. According to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area, and then potentially expand to the continental shelf and deep basin in the lower Cambrian. In these sections, the abundance, size, and diversity of monaxons increase upwards,followed by the appearance of diaxons, triaxons and then polyactines. Despite the uncertain affinity of the sponge fossils, it is possible that siliceous hexactinellids evolved later than siliceous demosponges, given that the earliest spicule assemblages are exclusively composed of monaxons, which commonly form bundles comparable to modern demosponges. New geochemical data from the Sifangjing section, Guizhou Province and the Yanziqiao section, Hunan Province, South China show that the appearance of sponges usually corresponds to anoxic environment. In addition, we applied the recently proposed Biological Pump, Oxygen and Phosphorus(BPOP) model to trace the evolution of oceanic oxygen concentrations with the radiation of sponges. The results indic

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Orbitronics for energy-efficient magnetization switching

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Science China(Information Sciences) 2025年第1期68卷 398-399页

作者： Yuxuan YAO Daoqian ZHU Qingtao XIA Jianing LIANG yuhao JIANG Zhiyang PENG Jiaxu LI Chen XIAO Renyou XU Wenwen WANG Xiantao SHANG Shiyang LU Dapeng ZHU Hong-Xi LIU Kaihua CAO Weisheng ZHAO Fert Beijing Institute School of Integrated Circuit Science and Engineering Beihang University National Key Lab of Spintronics Institute of International Innovation Beihang University Qingdao Research Institute Beihang University Truth Memory Corporation

Spin-orbit torque （SOT）,as a promising writing method for magnetic random-access memory （MRAM）,has garnered widespread interest for over a decade [1].Heavy metals,such as β-W,have been broadly adopted as spin current sources,but suffer from phase change at a limited thickness,resulting in a dramatic reduction of the charge-tospin conversion efficiency θSH[2].The thickness limitation leads to stringent etching conditions and large distribution among devices,posing challenges for simultaneously satisfying SOT efficiency,etching-stop margins,and back-end-ofline （BEOL） compatibility.

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Electromagnetic three-dimensional vibration energy harvester based on an oblique cross-spring vibrator structure

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Science China Technological Sciences 2025年第1期 189-206页

作者： Yaohui AN Yimin FAN Kefan XU yuhao CHEN Yewei ZHANG Liqun CHEN School of Science Harbin Institute of Technology College of Aerospace Engineering Shenyang Aerospace University

This paper presents an electromagnetic three-dimensional vibration energy harvesting device that uses an oblique cross-spring vibrator structure to collect low-frequency vibration energy. The oblique cross-spring structure allowed the center vibrator to vibrate in any direction. Together with six-directional coils, this configuration senses and harvests environmental vibrations across all directions and levels. First, the dynamics of the oblique cross-spring vibrator structure were analyzed and a finite element simulation was performed for the magnet arrangement and mode shape of the structure. A prototype is designed,fabricated, and experimentally verified. The results showed that the efficiency of the three-dimensional energy output was higher under the same excitation, which was 2.7 times higher than that of the unidirectional output. The unidirectional output power with load is 0.94 mW at 11 Hz under 0.3 g base excitation. The highest total output power of the prototype was 50 mW when it was fixed to the leg at a running speed of 8 km/h. Consequently, the energy harvesting scheme proposed in this study has a considerable low-frequency output effect, which provides a novel means of improving the electrical performance of energy harvesting systems for self-powered IoT and sensor devices.

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Near-field wideband beam training for ELAA with uniform circular array

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Science China(Information Sciences) 2024年第6期67卷 370-383页

作者： yuhao CHEN Linglong DAI Department of Electronic Engineering Tsinghua UniversityBeijing National Research Center for Information Science and Technology (BNRist)

Extremely large-scale antenna array(ELAA) at millimeter wave(mmWave) and Terahertz(THz)band has been considered a key technology for combating high attenuation in high-frequency bands in future6G communications. Uniform circular arrays(UCAs) have attracted much attention because of their ability to provide flat beamforming gain at all angles. To realize efficient beamforming, beam training is widely used to acquire channel state information. However, with a large antenna number, the beam training overhead in ELAA systems becomes overwhelming. moreover, with a large bandwidth, the beam defocus effect severely degrades beam training accuracy. To address these issues, this paper proposes a frequency-dependent focusing(FDF)-based beam training scheme to realize effective beam training in near-field wideband ELAA systems with UCA. Specifically, we first analyze the FDF property of UCA, where signals at different subcarriers can simultaneously focus on different distances. Then, by exploiting the FDF property to search different distances using different subcarriers simultaneously, we design a hierarchical codebook and propose an FDFbased beam training scheme. To reveal the effectiveness of the proposed scheme, we compare its necessary beam training overhead with that of existing schemes. Finally, the simulation results demonstrate that the proposed scheme can achieve accurate beam training in near-field wideband UCA systems with a low beam training overhead.

关键词： extremely large-scale antenna array (ELAA) uniform circular array (UCA) near-field wideband beam training

An Azo-PDMS-based wearable UV sensor with the optimized photo response mode for dual sensing and synchronous detection

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Science China(Technological Sciences) 2022年第1期65卷 179-190页

作者： QI yuhao ZHENG JunPing Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

A wearable UV sensor is designed to realize UV detection and a warning effect on people’s excessive UV *** is noteworthy that the photoelectric system and supporting material of the most conventional sensor are *** unstable connection between the two components and the complicated construction method makes the sensor susceptible to external motion interference and prone to ***,we developed a unique photo response mode of the UV sensor based on a novel photo responsive *** azobenzene-containing polydimethylsiloxane(Azo-PDMS)film was prepared as the outer layer of the *** integrated the functions of photo response source,support and protection,which realized the direct contact and rapid response to the UV light *** nanotube(CNT),wrapped in the middle of Azo-PDMS films as an inner layer,transformed the photomechanical response signal into the photoelectric *** photo response mode endows the sensor with excellent anti-motion interference capabilities and a true sense of UV-strain synchronous monitoring performance,which is of great significance to the practical application of wearable *** addition,based on the excellent properties of Azo-PDMS,the sensor can also protect the human body from UV damage,self-repair after fracture,and realize personalized customization through 3 D *** makes a breakthrough in the design and construction of wearable UV sensors and paves a new way to optimize sensor photo response modes.

关键词： azobenzene polydimethylsiloxane wearable UV sensor synchronous detection

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基于位图表征与U-Att分类网络的恶意软件识别技术

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信息安全研究 2025年第1期11卷 28-34页

作者：屈梦楠靳宇浩张光华河北科技大学信息科学与工程学院石家庄050018

在计算机安全领域,恶意软件识别一直是一个具有挑战性的任务,当前基于深度学习的恶意软件检测技术存在泛化能力不足、性能损耗高等诸多问题.为解决上述问题,提出一种基于位图表征与U-Att分类网络恶意软件识别新技术.U-Att分类网络在残差... 详细信息

在计算机安全领域,恶意软件识别一直是一个具有挑战性的任务,当前基于深度学习的恶意软件检测技术存在泛化能力不足、性能损耗高等诸多问题.为解决上述问题,提出一种基于位图表征与U-Att分类网络恶意软件识别新技术.U-Att分类网络在残差U-Net网络的基础上,结合了注意力分类器,自适应地聚焦于恶意样本的重要区域,从而提高分类性能.实验中使用多个公开数据集进行了验证,并与其他方法进行了比较分析.实验结果表明,该网络在恶意软件识别任务中取得了优越的性能且拥有更少的参数量.

关键词：恶意软件识别图像处理残差U-Net网络注意力机制

Risk-averse Contextual Multi-armed Bandit Problem with Linear Payoffs

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Journal of Systems Science and Systems Engineering 2023年第3期32卷 267-288页

作者： Yifan Lin yuhao Wang Enlu Zhou School of Industrial and Systems Engineering Georgia Institute of TechnologyAtlantaGAUSA

In this paper we consider the contextual multi-armed bandit problem for linear payoffs under a risk-averse *** each round,contexts are revealed for each arm,and the decision maker chooses one arm to pull and receives the corresponding *** particular,we consider mean-variance as the risk criterion,and the best arm is the one with the largest mean-variance *** apply the Thompson sampling algorithm for the disjoint model,and provide a comprehensive regret analysis for a variant of the proposed *** T rounds,K actions,and d-dimensional feature vectors,we prove a regret bound of O((1+ρ+1/ρ)d In T ln K/δ√dKT^(1+2∈)ln K/δ1/e)that holds with probability 1-δunder the mean-variance criterion with risk tolerance p,for any 0monstrated via a portfolio selection problem.

关键词： Multi-armed bandit context risk-averse Thompson sampling