Inspired by the recently predicted 2D MX_(2)Y_(6)(M=metal element;X=Si/Ge/Sn;Y=S/Se/Te),we explore the possible applications of alkaline earth metal(using magnesium as example)in this family based on the idea of eleme...Inspired by the recently predicted 2D MX_(2)Y_(6)(M=metal element;X=Si/Ge/Sn;Y=S/Se/Te),we explore the possible applications of alkaline earth metal(using magnesium as example)in this family based on the idea of element replacement and valence electron balance.Herein,we report a new family of 2D quaternary compounds,namely MgMX_(2)Y_(6)(M=Ti/Zr/Hf;X=Si/Ge;Y=S/Se/Te)monolayers,with superior kinetic,thermodynamic and mechanical stability.In addition,our results indicate that MgMX_(2)Y_(6)monolayers are all indirect band gap semiconductors with band gap values ranging from 0.870 to 2.500 eV.Moreover,the band edges and optical properties of 2D MgMX_(2)Y_(6)are suitable for constructing multifunctional optoelectronic devices.Furthermore,for comparison,the mechanical,electronic and optical properties of In_(2)X_(2)Y_(6)monolayers have been discussed in detail.The success of introducing Mg into the 2D MX_(2)Y_(6)family indicates that more potential materials,such as Caand Sr-based 2D MX_(2)Y_(6)monolayers,may be discovered in the future.Therefore,this work not only broadens the existing family of 2D semiconductors,but it also provides beneficial results for the future.展开更多
研究了不同烧结温度及恒温保持时间对富锂锰基正极材料Li1＋x[Ni0.35Mn0.65]O2＋y形貌、结构及电化学性能的影响。XRD及SEM研究结果表明：所合成的Li1＋x[Ni0.35Mn0.65]O2＋y正极材料为层状α-NaFeO2结构,类球形,单颗粒大小均匀。扣式...研究了不同烧结温度及恒温保持时间对富锂锰基正极材料Li1＋x[Ni0.35Mn0.65]O2＋y形貌、结构及电化学性能的影响。XRD及SEM研究结果表明：所合成的Li1＋x[Ni0.35Mn0.65]O2＋y正极材料为层状α-NaFeO2结构,类球形,单颗粒大小均匀。扣式电池测试结果表明：当电流密度为12.5 m A/g,测试电压在2.04.8 V时,Li1＋x[Ni0.35Mn0.65]O2＋y材料最高初始放电比容量为213.3 m A·h/g,首次放电效率为71.0%。扣电进行EIS测试,结果表明材料具有较小的电荷转移阻抗。展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 61974049, 62222404 61974050)National Key Research and Development Plan of China (Grant No. 2021YFB3601200)
文摘Inspired by the recently predicted 2D MX_(2)Y_(6)(M=metal element;X=Si/Ge/Sn;Y=S/Se/Te),we explore the possible applications of alkaline earth metal(using magnesium as example)in this family based on the idea of element replacement and valence electron balance.Herein,we report a new family of 2D quaternary compounds,namely MgMX_(2)Y_(6)(M=Ti/Zr/Hf;X=Si/Ge;Y=S/Se/Te)monolayers,with superior kinetic,thermodynamic and mechanical stability.In addition,our results indicate that MgMX_(2)Y_(6)monolayers are all indirect band gap semiconductors with band gap values ranging from 0.870 to 2.500 eV.Moreover,the band edges and optical properties of 2D MgMX_(2)Y_(6)are suitable for constructing multifunctional optoelectronic devices.Furthermore,for comparison,the mechanical,electronic and optical properties of In_(2)X_(2)Y_(6)monolayers have been discussed in detail.The success of introducing Mg into the 2D MX_(2)Y_(6)family indicates that more potential materials,such as Caand Sr-based 2D MX_(2)Y_(6)monolayers,may be discovered in the future.Therefore,this work not only broadens the existing family of 2D semiconductors,but it also provides beneficial results for the future.
文摘研究了不同烧结温度及恒温保持时间对富锂锰基正极材料Li1＋x[Ni0.35Mn0.65]O2＋y形貌、结构及电化学性能的影响。XRD及SEM研究结果表明：所合成的Li1＋x[Ni0.35Mn0.65]O2＋y正极材料为层状α-NaFeO2结构,类球形,单颗粒大小均匀。扣式电池测试结果表明：当电流密度为12.5 m A/g,测试电压在2.04.8 V时,Li1＋x[Ni0.35Mn0.65]O2＋y材料最高初始放电比容量为213.3 m A·h/g,首次放电效率为71.0%。扣电进行EIS测试,结果表明材料具有较小的电荷转移阻抗。
