利用表面光电压谱(SPS)和瞬态光伏(TRP)技术研究了纳米ZnO的光生电荷行为,发现TRP曲线时域为10-9~10-7和10-6~10-3s时样品的SPS在320~380 nm处出现光伏响应,时域为10-3~10-1s时样品的SPS在380~420 nm处出现光伏响应.这3个时域分别对应着纳米晶本征响应、晶间电荷转移和纳米晶表面态电荷捕获等过程.光生电荷密度足够大或受外部电场影响时在300~320 nm区间也出现光伏响应.
Transient photovoltaic technology(TRP) and surface photovoltaic spectrum(SPS) were used for studying the photogenerated charge of nano-ZnO.The results show that when the time domain of TRP range of 10-9—10-7 and 10-6—10-3 s,the photovoltage response of SPS appears in range of 320—380 nm.But when time domain is range of 10-3—10-1 s,the photovoltage appears in range of 380—420 nm.The three time domains of TRP were belonged to intrinsic transition of nanocrystals,the charge transfer between nanocrystals and surface-state trapping of nanocrystals,respectively.If the intensity of photocharge was large enough or an exexternal electric field was used,then the photovoltage also appeared in range of 300—320 nm.