Chen Zhitao, Yao Juan, Zhao Hongli, Bi Tengfei, Fu Yuechun, Shen Xiaoming, He Huan
Appl Opt. 2022 Oct 1;61(28):8376-8381. doi: 10.1364/AO.473483.
Porous ZnO nanosheets (ZnO NSs) may play an important role in self-powered UV photodetectors due to their excellent properties, and their porosity feature affects the photoresponse performance greatly. Porous ZnO NSs were prepared by the hydrothermal method followed with a one-step annealing treatment. The effects of the annealing temperature on the microstructure and photoresponse of porous ZnO NSs and n-ZnO NSs/p-PEDOT:PSS self-powered UV photodetectors were investigated. The results show that the pore density and size of ZnO NSs can be tuned by changing the annealing temperature. At an optimum annealing temperature of 450°C, ZnO NSs exhibit greater absorption capacity for the suitable pore density and size. Meanwhile, more crystal defects due to surface contractile properties increase the number of photogenerated carriers. On this basis, the n-ZnO NSs/p-PEDOT:PSS photodetector presents a larger photocurrent and fast photodetection speed without external bias voltage, indicating the self-powered performance. The higher light absorption and large number of electron-hole pairs resulting from dense pores and surface defects in porous ZnO NSs might account for the enhanced performances.
多孔氧化锌纳米片（ZnO NSs）因其优异的性能可能在自供电紫外光探测器中发挥重要作用，并且其孔隙率特征对光响应性能有很大影响。采用水热法并经过一步退火处理制备了多孔ZnO NSs。研究了退火温度对多孔ZnO NSs以及n-ZnO NSs/p-PEDOT:PSS自供电紫外光探测器的微观结构和光响应的影响。结果表明，通过改变退火温度可以调节ZnO NSs的孔隙密度和尺寸。在450°C的最佳退火温度下，ZnO NSs对于合适的孔隙密度和尺寸表现出更大的吸收能力。同时，由于表面收缩特性产生的更多晶体缺陷增加了光生载流子的数量。在此基础上，n-ZnO NSs/p-PEDOT:PSS光探测器在无外部偏置电压的情况下呈现出更大的光电流和快速的光探测速度，表明其具有自供电性能。多孔ZnO NSs中密集的孔隙和表面缺陷导致的更高光吸收和大量电子-空穴对可能是性能增强的原因。
