High sensitivity UV photodetectors based on low-cost TiO2P25-graphene hybrids

Zilong Chen; Zhaowei Zhu; Liting Huang; Chuantong Cheng

doi:10.1088/1361-6528/ac3a37

High sensitivity UV photodetectors based on low-cost TiO₂P25-graphene hybrids

Nanotechnology. 2021 Nov 30;33(8). doi: 10.1088/1361-6528/ac3a37.

Authors

Zilong Chen^{1

2}, Zhaowei Zhu¹, Liting Huang¹, Chuantong Cheng³

Affiliations

¹ College of Science, China Agricultural University, Beijing 100083, People's Republic of China.
² Syracuse University, 900 South Crouse Ave. Syracuse, NY 13244, United States of America.
³ State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, People's Republic of China.

PMID: 34787105
DOI: 10.1088/1361-6528/ac3a37

Abstract

Photodetectors (PDs) are the core component of multiple commercial optical sensing systems. Currently, the detection of ultra-weak ultraviolet (UV) optical signals is becoming increasingly important for wide range of applications in civil and military industries. Due to its wide band gap, low cost, and long-term stability, titanium dioxide (TiO₂) is an attractive material for UV photodetection. A kind of low-cost TiO₂nanomaterial (named as P25) manufactured by flame hydrolysis is an easily available commercial material. However, a low-cost and high-sensitivity UV PD based on P25 has not been achieved until now. Here, a hybrid UV PD with monolayer CVD graphene covered by a thin film of P25 quantum dots was prepared for the first time, and its responsivity was approximately 10⁵A W^-1at 365 nm wavelength. The response time and recovery time of the UV PD were 32.6 s and 34 s, respectively. Strong light absorption and photocontrolled oxygen adsorption of the P25 layer resulted in high UV sensitivity. The UV PDs proposed in this work have great potential for commercialization due to their low cost and high sensitivity.

Keywords: P25 coating; graphene photodetector; high photoresponsivity; low-cost; ultraviolet sensor.