氧化锌压电纳米发电机的频域特性仿真

Frequency-domain simulation of zinc oxide piezoelectric nanogenerator

ZnO压电纳米发电机是一种可在纳米尺度将机械能转换成电能的绿色能源器件,具有敏感度高、响应迅速、制备工艺简单等特点。如何有效提高压电纳米发电机的输出性能是该领域的研究热点。为了确定ZnO压电纳米发电机在构成电路系统时的输出特性,采用有限元仿真软件COMSOL Multiphysics,针对两种不同形貌的ZnO纳米线结构,建立了相应的电路系统。在频域中,分析了振动频率、外接负载阻值、振动加速度、纳米线斜度与形貌五种因素对外接负载输出电压和功率的影响。结果表明:倾斜角为15°的平顶圆柱纳米线模型为最优模型结构,振动频率为400 Hz时,单根纳米线的峰值电压和峰值功率分别达到1.64 V和42.51 nW。

ZnO piezoelectric nanogenerator is a green energy device which can convert mechanical energy to electrical energy in nano-scale,with the advantages of high sensitivity,rapid response,and easy fabrication.How to effectively enhance the output performance of piezoelectric nanogenerator is one of the research hotspots in this field.In order to determine the output characteristics of ZnO piezoelectric nanogenerator,the COMSOL Multiphysics simulation software was employed to establish the corresponding circuit system for two different morphologies of ZnO nanowires.In frequency-domain analysis,the influences of five factors on the output voltage and power were investigated,including the vibrational frequency,external load resistance,vibrational acceleration,nanowire slope and morphology.Among them,the vibrational frequency and load resistance are the most significant influencing factors.The results indicate that the flat-topped nanowire model with an inclination angle of 15°is the optimal model structure.Meanwhile,the peak voltage and power of the single nanowire can reach up to 1.64 V and 42.51 nW at 400 Hz,respectively.