Facile Synthesis of γ-In2 Se3 Nanoflowers toward High Performance Self-Powered Broadband γ-In2 Se3 /Si Heterojunction Photodiode

An effective colloidal process involving the hot-injection method is developed to synthesize uniform nanoflowers consisting of 2D γ-In2 Se3 nanosheets. By exploiting the narrow direct bandgap and high absorption coefficient in the visible light range of In2 Se3 , a high-quality γ-In2 Se3 /Si heterojunction photodiode is fabricated. This photodiode shows a high photoresponse under light illumination, short response/recovery times, and long-term durability. In addition, the γ-In2 Se3 /Si heterojunction photodiode is self-powered and displays a broadband spectral response ranging from UV to IR with a high responsivity and detectivity. These excellent performances make the γ-In2 Se3 /Si heterojunction very interesting as highly efficient photodetectors.