Large bandgap reduced graphene oxide (rGO) based n-p ⁺ heterojunction photodetector with improved NIR performance

Abstract

Integration of two-dimensional reduced graphene oxide (rGO) with conventional Si semiconductor offers novel strategies for realizing broadband photodiode with enhanced device performance. In this quest, we have synthesized large bandgap rGO and fabricated metal-free broadband (300-1100 nm) back-to-back connected np-pn hybrid photodetector utilizing drop casted n-rGO/p + -Si heterojunctions with high performance in NIR region (830 nm). With controlled illumination, the device exhibited a peak responsivity of 16.7 A W −1 and peak detectivity of 2.56×10 12 Jones under 830 nm illumination (11 μW cm −2 ) at 1 V applied bias with fast response (∼460 μs) and recovery time (∼446 μs). The fabricated device demonstrated excellent repeatability, durability and photoswitching behavior with high external quantum efficiency (∼2.5×10 3 %), along with ultrasensitive behavior at low light conditions.

Solution-Processed SnSe2–RGO-Based Bulk Heterojunction for Self-Powered and Broadband Photodetection

“…To understand the mechanism of carrier transport and the self-powered behavior, an energy band diagram of the PD is shown in Figure a. The work functions of RGO (−4.7 eV), SnSe 2 (−4.8 eV), and MoS 2 (−4.2 eV) have been taken from the literature. ,− The charge transfer mechanism at the SnSe 2 –RGO heterojunction can be understood by the use of the donor–acceptor bulk heterojunction commonly used in organic solar cells . Here, the bulk heterojunction is generated by an interpenetrating network of SnSe 2 and RGO in which SnSe 2 microspikes are wrapped with RGO sheets that provides a large interfacial area.…”

Computational studies of ionic liquids as co-catalyst for CO2 electrochemical reduction to produce syngas using COSMO-RS

“…The reason for choosing these anions and cations is the availability of their CO2ERR performance data from the literatures that are reported by Vasilyev and Rosen [6,7]. The LUMO values from experimental data [6,7] were calculated approximately based on the onset potential of reduction of the ionic liquids following Equation 1 [21].…”

Modeling the time-dependent characteristics of perovskite solar cells

“…We use graphene based devices it has attracted the attention of many researchers not only for solar cell ap-plication but also for sensors, photodetectors, LEDs, etc. over 100 pa-pers have been published last year on graphene application in per-ovskite solar cells (Son et al, 2017;Singh et al, 2018). The recent review on these hybrid devices shows a power conversion efficiency between 10% and 15% for graphene and inorganic semiconductorbased hybrid heterojunction solar cells, and 15.6% for graphene-con-taining perovskite cells.…”