Ultra-homogeneous dense Ag nano layer enables long lifespan solid-state lithium metal batteries

The unstable electrolyte/lithium(Li)anode interface has been one of the key challenges in realizing high energy density solid-state lithium metal batteries(LMBs)applications.Herein,a dense and uniform silver(Ag)nano interlayer with a thickness of∼35 nm is designed accurately by magnetron sputtering technology to optimize the electrolyte/Li anode interface.This Ag nano layer reacts with Li metal anode to in-situ form Li-Ag alloy,thus enhancing the physical interfacial contact,and further improving the interfacial wettability and compatibility.In particular,the Li-Ag alloy is inclined to form AgLi phase proved by cryo-TEM and DFT,effectively preventing SN from continuously“attacking”the Li metal anode due to the lower adsorption of succinonitrile(SN)molecules on AgLi than that of pure Li metal,thereby significantly reinforcing the interfacial stability.Hence,the enhanced physical and chemical stability of electrolyte/Li anode interface promotes the homogeneous deposition of Li^(+)and inhibits the dendrite growth.The Li-symmetric cell maintains stable operation for up to 1700 h and the cycling stability of LiFePO_(4)|SPE|Li full cell is remarkably improved at room temperature(capacity retention rate of 91.9%for 200 cycles).This work opens an effective way for accurate and controllable interface design of long lifespan solid-state LMBs.

硅烷化银涂层钛植入物的抗菌改性研究

对钛种植体进行表面改性处理需要满足抗菌性和生物相容性的要求,才能保证植入的成功。采用不同表面改性方法对钛表面的形态特征、抗菌性和生物相容性进行了研究,结果表明:钛片经酸蚀和碱热改性处理后,其表面生成了均匀分布的三维网状结构,提高了钛片的亲水性和粗糙度,增强了钛片的生物活性,同时促进了细胞黏附;采用硝酸银和柠檬酸三钠,通过化学反应成功制备出了银纳米颗粒;硅烷化处理的钛片浸泡在合成的纳米银液中,成功在钛片表面构建出了载银抗菌涂层。同时经酸蚀碱热处理的钛片,硅烷化改性2 h后,银包覆钛底物具有最高的抗菌性和生物相容性。研究成果可为医疗用钛植入物的生产提供借鉴。