为解决TiO₂纳米颗粒紫外光探测器难以兼具高光响应度和快响应速率的问题，制备了MgO阻挡层/TiO₂纳米颗粒复合结构的自供电紫外光探测器。其中，具有多分枝结构的TiO₂纳米颗粒提供较大比表面积，吸收紫外光子产生大量电子-空穴对；而MgO阻挡层的主要作用是阻止电子和空穴复合，从而减少电子传输过程中的损失。该复合结构紫外光探测器具有自供电性能，且兼具高光响应度（0.76 A/W）和快响应速率（上升时间和恢复时间分别为2.5 s和8.1 s），与其他TiO₂纳米结构紫外光探测器相比性能优异。

Titanium oxide (TiO₂) with a rutile structure,which possesses a band-gap of 3.02 eV at 300 K,is widely used for ultraviolet (UV) detector.However,the TiO₂ nanoparticles (NPs) based UV detectors are difficult to obtain high photoresponsivity and fast response speed at the same time.A self-powered UV detector composing of MgO blocking layer/TiO₂ NPs is successfully fabricated.This MgO/TiO₂ NPs based UV detector exhibits superior performance than most reported TiO₂ nanostructure based UV detectors.It shows simultaneously an excellent responsivity (0.76 A·W^-1) and quick response speed (its rising time and decaying time are 2.5 s and 8.1 s,respectively).TiO₂ NPs with abundant branches can provide large specific surface area to absorb the massive electron hole pair generated by UV.MgO ultrathin layer is fabricated on the surface of substrate directly,which can effectively reduce wastage and recombination between electrons and holes in the boundary.In addition,this MgO/TiO₂ NPs UV detector shows significant selectivity of UV light.

董雅楠(1992-),女,硕士研究生,研究方向为纳米材料紫外光探测器,Dong_YN@163.com