Mn-based layered oxides(KMO)have emerged as one of the promising low-cost cathodes for potassiumion batteries(PIBs).However,due to the multiple-phase transitions and the distortion in the MnO6structure induced by the ...Mn-based layered oxides(KMO)have emerged as one of the promising low-cost cathodes for potassiumion batteries(PIBs).However,due to the multiple-phase transitions and the distortion in the MnO6structure induced by the Jahn-Teller(JT)effect associated with Mn-ion,the cathode exhibits poor structural stability.Herein,we propose a strategy to enhance structural stability by introducing robust metal-oxygen(M-O)bonds,which can realize the pinning effect to constrain the distortion in the transition metal(TM)layer.Concurrently,all the elements employed have exceptionally high crustal abundance.As a proof of concept,the designed K_(0.5)Mn_(0.9)Mg_(0.025)Ti_(0.025)Al_(0.05)O_(2)cathode exhibited a discharge capacity of approximately 100 mA h g^(-1)at 20 mA g^(-1)with 79%capacity retention over 50 cycles,and 73%capacity retention over 200 cycles at 200 mA g^(-1),showcased much better battery performance than the designed cathode with less robust M-O bonds.The properties of the formed M-O bonds were investigated using theoretical calculations.The enhanced dynamics,mitigated JT effect,and improved structural stability were elucidated through the in-situ X-ray diffractometer(XRD),in-situ electrochemical impedance spectroscopy(EIS)(and distribution of relaxation times(DRT)method),and ex-situ X-ray absorption fine structure(XAFS)tests.This study holds substantial reference value for the future design of costeffective Mn-based layered cathodes for PIBs.展开更多
随着人们出行需求日益提升,铁路行业面临着运营成本上升、基础设施老化等一系列挑战。为此,铁路行业积极探索应用数字孪生技术,推动全行业数字化智能化发展。以中国知网及Web of Science核心数据库中关于铁路行业数字孪生的国内外相关...随着人们出行需求日益提升,铁路行业面临着运营成本上升、基础设施老化等一系列挑战。为此,铁路行业积极探索应用数字孪生技术,推动全行业数字化智能化发展。以中国知网及Web of Science核心数据库中关于铁路行业数字孪生的国内外相关文献为研究对象,从国内外2方面整理和分析数字铁路应用规划及数字孪生底座相关技术在工程建设、基础设施运维、日常运营中的应用。综合分析目前理论研究与实践应用,结果表明:数字孪生技术在铁路行业中具有广阔的应用前景,将极大推动行业的发展和进步。展开更多
基金Foundation item:supported by Science and Technology Foundation of Shanghai Higher Education(01D01-2)and the Foundation of Ministry of Education for Core Teachers of Higher Education.
基金financially supported by the National Natural Science Foundation of China(NSFC)(52274295)the Natural Science Foundation of Hebei Province(E2021501029)+3 种基金the Fundamental Research Funds for the Central Universities(N2423051,N2423053,N2302016,N2423019,N2323013,N2423005)the Science and Technology Project of Hebei Education Department(QN2024238)the Basic Research Program Project of Shijiazhuang City for Universities Stationed in Hebei Province(241790937A)the Science and Technology Project of Qinhuangdao City in 2023.
文摘Mn-based layered oxides(KMO)have emerged as one of the promising low-cost cathodes for potassiumion batteries(PIBs).However,due to the multiple-phase transitions and the distortion in the MnO6structure induced by the Jahn-Teller(JT)effect associated with Mn-ion,the cathode exhibits poor structural stability.Herein,we propose a strategy to enhance structural stability by introducing robust metal-oxygen(M-O)bonds,which can realize the pinning effect to constrain the distortion in the transition metal(TM)layer.Concurrently,all the elements employed have exceptionally high crustal abundance.As a proof of concept,the designed K_(0.5)Mn_(0.9)Mg_(0.025)Ti_(0.025)Al_(0.05)O_(2)cathode exhibited a discharge capacity of approximately 100 mA h g^(-1)at 20 mA g^(-1)with 79%capacity retention over 50 cycles,and 73%capacity retention over 200 cycles at 200 mA g^(-1),showcased much better battery performance than the designed cathode with less robust M-O bonds.The properties of the formed M-O bonds were investigated using theoretical calculations.The enhanced dynamics,mitigated JT effect,and improved structural stability were elucidated through the in-situ X-ray diffractometer(XRD),in-situ electrochemical impedance spectroscopy(EIS)(and distribution of relaxation times(DRT)method),and ex-situ X-ray absorption fine structure(XAFS)tests.This study holds substantial reference value for the future design of costeffective Mn-based layered cathodes for PIBs.
文摘随着人们出行需求日益提升,铁路行业面临着运营成本上升、基础设施老化等一系列挑战。为此,铁路行业积极探索应用数字孪生技术,推动全行业数字化智能化发展。以中国知网及Web of Science核心数据库中关于铁路行业数字孪生的国内外相关文献为研究对象,从国内外2方面整理和分析数字铁路应用规划及数字孪生底座相关技术在工程建设、基础设施运维、日常运营中的应用。综合分析目前理论研究与实践应用,结果表明:数字孪生技术在铁路行业中具有广阔的应用前景,将极大推动行业的发展和进步。
