摘要
Lead-free relaxor ceramics(1−x)K_(0.5)Na_(0.5)NbO_(3)−xBi(Mn_(0.5)Ni_(0.5))O_(3)((1−x)KNN-xBMN)with considerable charge-discharge characteristics and energy storage properties were prepared by a solid state method.Remarkable,a BMN doping level of 0.04,0.96KNN-0.04BMN ceramic obtained good energy storage performance with acceptable energy storage density Wrec of 1.826 J/cm^(3) and energy storage efficiencyηof 77.4%,as well as good frequency stability(1-500 Hz)and fatigue resistance(1-5000 cycles).Meanwhile,a satisfactory charge-discharge performance with power density PD~98.90 MW/cm^(3),discharge time t0.9<70 ns and temperature stability(30-180°C)was obtained in 0.96KNN-0.04BMN ceramic.The small grain size(~150 nm)and the high polarizability of Bi3+are directly related to its good energy storage capacity.This work proposes a feasible approach for lead-free KNN-based ceramics to achieve high-energy storage and ultra-fast charge-discharge performance as well as candidate materials for the application of advanced high-temperature pulse capacitors.
基金
supported by the National Natural Science Foundation of China(NSFC)(Grant No.52272119,51872177)
the Natural Science Basic Research Plan in the Shaanxi Province of China(Grant No.2021ZDLSF06-03,2021JM-201)
the Fundamental Research Funds for the Central Universities(Program No.GK202002014)
the Fondamental Innovation Project in School of Materials Science and Engineering(SNNU).
