title: Piezo-phototronic Effect Enhanced UV/Visible Photodetector Based on Fully Wide Band Gap Type-II ZnO/ZnS Core/Shell Nanowire Array.
abstract: A high-performance broad band UV/visible photodetector has been successfully fabricated on a fully wide bandgap ZnO/ZnS type-II heterojunction core/shell nanowire array. The device can detect photons with energies significantly smaller (2.2 eV) than the band gap of ZnO (3.2 eV) and ZnS (3.7 eV), which is mainly attributed to spatially indirect type-II transition facilitated by the abrupt interface between the ZnO core and ZnS shell. The performance of the device was further enhanced through the piezo-phototronic effect induced lowering of the barrier height to allow charge carrier transport across the ZnO/ZnS interface, resulting in three orders of relative responsivity change measured at three different excitation wavelengths (385, 465, and 520 nm). This work demonstrates a prototype UV/visible photodetector based on the truly wide band gap semiconducting 3D core/shell nanowire array with enhanced performance through the piezo-phototronic effect.
authors.affiliation: †Advanced Materials Research Institute, University of New Orleans, New Orleans, Louisiana 70148, United States.
authors.forename: Satish C
authors.initials: SC
authors.lastname: Rai
authors.affiliation: †Advanced Materials Research Institute, University of New Orleans, New Orleans, Louisiana 70148, United States.
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.affiliation: ‡School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ding
authors.affiliation: ¶Nanoscale Science, University of North Carolina, Charlotte, North Carolina 28223, United States.
authors.forename: Jason K
authors.initials: JK
authors.lastname: Marmon
authors.affiliation: †Advanced Materials Research Institute, University of New Orleans, New Orleans, Louisiana 70148, United States.
authors.forename: Manish
authors.initials: M
authors.lastname: Bhatt
authors.affiliation: ¥Department of Electrical and Computer Engineering/Optoelectronic Center, University of North Carolina, Charlotte, North Carolina 28223, United States.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: †Advanced Materials Research Institute, University of New Orleans, New Orleans, Louisiana 70148, United States.
authors.forename: Weilie
authors.initials: W
authors.lastname: Zhou
authors.affiliation: ‡School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.|§Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, 100083 Beijing, China.
authors.forename: Zhong Lin
authors.initials: ZL
authors.lastname: Wang
keywords: UV/visible photodetector; core/shell nanowire; piezo-phototronic effect; type-II heterojunction