P-Bi2Te3/MXene超结构钾离子电池负极制备及其性能

Bi₂Te₃钾离子电池负极存在结构不稳定性和电化学反应动力学缓慢问题。本研究在手风琴状MXene基底上生长棒状Bi₂Te₃,随后利用P掺杂制备了高性能P-Bi₂Te₃/MXene超结构。这种新型负极具有丰富的Te空位和良好的自适应特性,展现出优异的循环稳定性(在0.2 A·g^-1电流密度下200次循环后可逆容量为323.1 mAh·g^-1)和出色的倍率能力(20 A·g^-1时可逆容量为67.1 mAh·g^-1)。动力学分析和非原位表征表明,该超结构具有优异的赝电容特性、出色的K⁺离子扩散能力以及可逆的嵌入反应和转化反应机理。     

Understanding oxygen reactions in aprotic Li-O_2 batteries

Although significant progress has been made in many aspects of the emerging aprotic Li-O_2 battery system, an indepth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the positive electrode distinguish Li-O_2 batteries from the conventional Li-ion cells and play a crucial role in the Li-O_2cell's performance(capacity, rate capability, and cycle life). Recent advances in fundamental studies of oxygen reactions in aprotic Li-O_2 batteries are reviewed, including the reaction route, kinetics, morphological evolution of Li_2O_2, and charge transport within Li_2O_2. Prospects are also provided for future fundamental investigations of Li-O_2 chemistry.