二维层状In2Se3铁电材料的光敏传感性能研究

Photosensitive Sensing Properties of Two-dimensional Layered In2Se3 Ferroelectric Materials

α-In2Se3是一种同时具有稳定面内和面外极化的窄禁带二维铁电材料,探究其铁电极化与光电导性能关联对促进其光敏传感器的应用具有重要意义.该文采用微机械剥离法获得了平面尺寸在50μm以上的α-In2Se3纳米片,利用原子力显微镜研究了其自发极化特性.制备了Pt/α-In2Se3/Pt光敏器件单元,研究了明暗条件下Pt/α-In2Se3/Pt器件单元I-V特性以及高压极化对光敏性能的影响.结果表明:二维层状α-In2Se3具有较好的光敏性能,且高压极化将大幅优化器件的光敏特性.高压极化使器件的响应时间明显缩短,1V电压明暗条件开关比提高至10^3以上.可见,铁电极化对于α-In2Se3纳米片的光电导效应具有重要影响,高压极化操作能够有效地提高其光敏性能.

α-In2Se3 is a narrow band gap two-dimensional ferroelectric material with stable in-plane and out-of-plane polarization.It is important to explore the relationship between ferroelectric polarization and photoconductivity to promote the application of photosensors.In this work,a α-In2Se3 nanosheet with a planar size over 50μm was obtained by micromechanical exfoliation method.The spontaneous polarization characteristics were studied by piezoelectric atomic force microscopy.Based on the above results,Pt/α-In2Se3 /Pt photosensor units were fabricated to study the photoconductive performance,I-V characteristics and the effect of high-voltage polarization.The results show that the two-dimensional α-In2Se3 has good photosensitivity,and high-voltage polarization will greatly optimize the performance of the device.After high-voltage polarization,the response time of the device is significantly shortened,and the current ratio in light/dark exceeds 10 3.It implies that ferroelectric polarization has an important influence on the photoconductive effect of α-In2Se3 nanosheets,and high-voltage polarization operation can effectively improve its photosensitivity.