MXene材料由于其独特的二维结构在储能领域受到了广泛的关注.通过对V 2AlC陶瓷粉体中Al层原子的选择性刻蚀可以制备出V2CTx二维纳米材料,其作为锂离子电池负极材料具有高的理论比容量,然而其刻蚀过程较为困难,且刻蚀产物表面的官能团显...MXene材料由于其独特的二维结构在储能领域受到了广泛的关注.通过对V 2AlC陶瓷粉体中Al层原子的选择性刻蚀可以制备出V2CTx二维纳米材料,其作为锂离子电池负极材料具有高的理论比容量,然而其刻蚀过程较为困难,且刻蚀产物表面的官能团显著影响其电化学性能.本论文采用HF以及HCl/NaF这两种刻蚀剂制备出了V2CTx二维材料,利用XRD、SEM、EDS和电化学工作站研究了其晶相、形貌结构和电化学性能.结果表明,采用HF做刻蚀剂得到的V2CTx在大电流密度下具有较好的循环性能,在0.1 A g-1的电流密度下循环100次,放电比容量分别为248 mAh g-1;在1A g-1的电流密度下循环1000次,可逆比容量分别为94 mAh g-1.展开更多
A self-powered ultraviolet photodetector(UV PD)with van der Waals(vdW)Schottky junction based on TiO_(2) nanorod arrays/Au-modulated V2 CTx MXene is reported.The Schottky junction enables the device to operate in self...A self-powered ultraviolet photodetector(UV PD)with van der Waals(vdW)Schottky junction based on TiO_(2) nanorod arrays/Au-modulated V2 CTx MXene is reported.The Schottky junction enables the device to operate in self-powered mode.The dangling bond-free surface of V2 CTx MXene reduces the charge recombination at the junction interface.Meanwhile,V2 CTx MXene,with the work function(WF)increasing to 5.35 eV,forms a hole transport layer by contacting with Au electrode,which facilitates the carrier extraction.The electron lifetime in the device has prolonged to 8.95μs.As a result,the responsivity and detectivity of the PD have achieved 28 mA/W and 1.2×10^(11) cm Hz1/2/W(340 nm,65 mW/cm2,0 V),respectively.In addition,the presence of the Au electrode prevents the vanadium from coming into contact with oxygen and oxidizing,preserving the properties of the V2 CTx films.After 180 days of exposure to the atmosphere,the device performance remained at a particularly high level,indicating enhanced durability.This work points out an effective approach to modulate the properties of V2 CTx to obtain the high performance and stability of the UV PD.展开更多
Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we id...Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we identify 63 genes significantly associated with maize embryo/kernel weight ratio using a genome-wide association study(GWAS).The peak GWAS signal shows that the natural variation in Zea mays COMPACT PLANT2(CT2),encoding the heterotrimeric G proteinαsubunit,is significantly associated with the Embryo/Kernel Weight Ratio(EKWR).Further analyses show that a missense mutation of CT2 increases its enzyme activity and associates with EKWR.The function of CT2 on affecting embryo/kernel weight ratio is further validated by the characterization of two ct2 mutants,for which EKWR is significantly decreased.Subsequently,the key downstream genes of CT2 are identified by combining the differential expression analysis of the ct2 mutant and quantitative trait transcript analysis in the GWAS population.In addition,the allele frequency spectrum shows that CT2 was under selective pressure during maize domestication.This study provides important genetic insights into the natural variation of maize embryo/kernel weight ratio,which could be applied in future maize breeding programs to improve grain yield and nutritional content.展开更多
文摘MXene材料由于其独特的二维结构在储能领域受到了广泛的关注.通过对V 2AlC陶瓷粉体中Al层原子的选择性刻蚀可以制备出V2CTx二维纳米材料,其作为锂离子电池负极材料具有高的理论比容量,然而其刻蚀过程较为困难,且刻蚀产物表面的官能团显著影响其电化学性能.本论文采用HF以及HCl/NaF这两种刻蚀剂制备出了V2CTx二维材料,利用XRD、SEM、EDS和电化学工作站研究了其晶相、形貌结构和电化学性能.结果表明,采用HF做刻蚀剂得到的V2CTx在大电流密度下具有较好的循环性能,在0.1 A g-1的电流密度下循环100次,放电比容量分别为248 mAh g-1;在1A g-1的电流密度下循环1000次,可逆比容量分别为94 mAh g-1.
基金supported by the National Natural Science Foun-dation of China(NSFC,52072207)Guizhou Provincial Science and Technology Projects(Grant Nos.ZK[2023]YB145,ZK[2023]YB149,and ZK[2022]214)+1 种基金Science and Technology Project of Guizhou Provincial Education Department(Grant Nos.[2022]143,[2022]150,and KY[2022]173)Science and Technology Foundation of Guizhou Minzu University(Grant Nos.GZMUZK[2022]YB21 and GZ-MUSYS[2021]02)。
文摘A self-powered ultraviolet photodetector(UV PD)with van der Waals(vdW)Schottky junction based on TiO_(2) nanorod arrays/Au-modulated V2 CTx MXene is reported.The Schottky junction enables the device to operate in self-powered mode.The dangling bond-free surface of V2 CTx MXene reduces the charge recombination at the junction interface.Meanwhile,V2 CTx MXene,with the work function(WF)increasing to 5.35 eV,forms a hole transport layer by contacting with Au electrode,which facilitates the carrier extraction.The electron lifetime in the device has prolonged to 8.95μs.As a result,the responsivity and detectivity of the PD have achieved 28 mA/W and 1.2×10^(11) cm Hz1/2/W(340 nm,65 mW/cm2,0 V),respectively.In addition,the presence of the Au electrode prevents the vanadium from coming into contact with oxygen and oxidizing,preserving the properties of the V2 CTx films.After 180 days of exposure to the atmosphere,the device performance remained at a particularly high level,indicating enhanced durability.This work points out an effective approach to modulate the properties of V2 CTx to obtain the high performance and stability of the UV PD.
基金supported by National Key Research and Development Program of China(2023YFF1000400)National Natural Science Foundation of China(32101693)+2 种基金Key Research and Development Program of Shaanxi(2021ZDLNY01-06)Agricultural Science and Technology Innovation Program of CAAS(CAAS-ZDRW202004)supported by Hatch project(1019088).
文摘Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we identify 63 genes significantly associated with maize embryo/kernel weight ratio using a genome-wide association study(GWAS).The peak GWAS signal shows that the natural variation in Zea mays COMPACT PLANT2(CT2),encoding the heterotrimeric G proteinαsubunit,is significantly associated with the Embryo/Kernel Weight Ratio(EKWR).Further analyses show that a missense mutation of CT2 increases its enzyme activity and associates with EKWR.The function of CT2 on affecting embryo/kernel weight ratio is further validated by the characterization of two ct2 mutants,for which EKWR is significantly decreased.Subsequently,the key downstream genes of CT2 are identified by combining the differential expression analysis of the ct2 mutant and quantitative trait transcript analysis in the GWAS population.In addition,the allele frequency spectrum shows that CT2 was under selective pressure during maize domestication.This study provides important genetic insights into the natural variation of maize embryo/kernel weight ratio,which could be applied in future maize breeding programs to improve grain yield and nutritional content.
