High-performance ultraviolet photodetectors based on solution-grown ZnS nanobelts sandwiched between graphene layers.

Yeonho Kim,Byung Hee Hong,Sung-Pyo Cho,Sang Jin Kim,Du-Jeon Jang

doi:10.1038/srep12345

Abstract

Ultraviolet (UV) light photodetectors constructed from solely inorganic semiconductors still remain unsatisfactory because of their low electrical performances. To overcome this limitation, the hybridization is one of the key approaches that have been recently adopted to enhance the photocurrent. High-performance UV photodetectors showing stable on-off switching and excellent spectral selectivity have been fabricated based on the hybrid structure of solution-grown ZnS nanobelts and CVD-grown graphene. Sandwiched structures and multilayer stacking strategies have been applied to expand effective junction between graphene and photoactive ZnS nanobelts. A multiply sandwich-structured photodetector of graphene/ZnS has shown a photocurrent of 0.115 mA under illumination of 1.2 mWcm−2 in air at a bias of 1.0 V, which is higher 107 times than literature values. The multiple-sandwich structure of UV-light sensors with graphene having high conductivity, flexibility, and impermeability is suggested to be beneficial for the facile fabrication of UV photodetectors with extremely efficient performances.

Highlights

Semiconductors has demonstrated enhanced performances for UV-light photodetection, their heterostructures still suffer from the small area of the effective-junction region contributing to the photocurrent[34,35,36]
We present that high-performance UV photodetectors showing stable on-off switching and spectral selectivity have been fabricated via a facile process based on the hybrid structure of solution-grown ZnS nanobelts and chemical vapor deposition (CVD)-grown graphene
An optimized photodetector based on S-graphene and ZnS (G/ZnS) shows a high photocurrent of 37 μ A, which is higher 106 times than the reported values of graphene-free UV photodetectors based on ZnS nanobelts[16] and ZnS-ZnO nanowires[11]

Summary

Introduction

Semiconductors has demonstrated enhanced performances for UV-light photodetection, their heterostructures still suffer from the small area of the effective-junction region contributing to the photocurrent[34,35,36]. We present that high-performance UV photodetectors showing stable on-off switching and spectral selectivity have been fabricated via a facile process based on the hybrid structure of solution-grown ZnS nanobelts and CVD-grown graphene. Sandwich structures and multi-layer stacking strategies have been applied to the photodetectors for the increment of the effective-junction region between graphene and ZnS. An optimized photodetector based on S-G/ZnS shows a high photocurrent of 37 μ A, which is higher 106 times than the reported values of graphene-free UV photodetectors based on ZnS nanobelts[16] and ZnS-ZnO nanowires[11]

Methods

Results

Conclusion