SnOx embedded into 3D RGO network for enhanced photoconductive performance

In this study, tin dioxide with vacancies (SnOx) was compounded with three-dimensional reduced graphene oxide (3D RGO) to obtain SnOx/3D RGO. The morphology, optical properties and structural composition of SnOx/3D RGO were analyzed by a series of techniques, and the photoconductive properties of the SnOx/3D RGO composites with different mass fractions of RGO were investigated. The photocurrent density of SnOx/3D RGO at 3D RGO mass fraction of 1.5 % reached a maximum value of 2.77 × 10−4 A/cm2, which was about twice and 1.2 times as large as that of SnOx and SnOx/2D RGO (two-dimensional reduced graphene oxide), respectively. In the linear scanning voltammetry and Mott-Schottky analysis results, SnOx/3D RGO exhibited the highest photocurrent (6.34 × 10−3 A/cm2) intensity at 1.0 V bias and the largest carrier density (2.61 × 1021cm−3). This was due to the fact that RGO played a charge transfer role in the composite material in both 2D and 3D structures. In contrast, the porous 3D RGO could connect separate lamellae, which prevented the aggregation of layers and enhanced the electron transfer, thus exhibiting superior performance than 2D graphene.