Nitrogen-Functionalized p-Type Graphene Window and Silicon Nanowire Heterostructure with High-Performing NIR Light Detection

Abstract

In recent development, the type of dopants, strain, vacancies, and band alignment in reduced graphene oxide, namely, graphene window, can be a promising candidate to exhibit high near-infrared light detection. In this work, we delineate structural effects, in-plane hopping defects, and vacancies that enhance p-type behavior of nitrogen/oxygen functionalized reduced graphene oxide (NORG). The NORG-6/30 has been prepared from pyrazole at different time intervals (6–30 h). A combined spectroscopic approach and ab initio calculation imply pyrazole-based 4-pyrrole unit complex macrocyclic unit formation, i.e., in-plane hopping defect and vacancies are maximum for NORG-30. Thus, the structural effect in NORG-30 opens the band gap and work function, shifts the Fermi level position toward the valence band, and increases the hole doping concentrations. The suitable band alignment between different layered NORG-30 and Silicon nanowire substrate shows remarkable NIR-based photodetector devices having maximum responsivity and detectivity as high as 50 mA W ^–1 and 2.2 × 10¹¹ Jones at −2 V. The temperature-dependent Thermionic and Cheung’s models are introduced to estimate the Schottky barrier height of 0.98 eV and the diode ideality factor of 2.92, which are well corroborated with UPS analysis. The high photocurrent from photoexcited high charge carrier formation of the NORG-30/SiNW device is 2 orders higher in magnitude than other NORG/SiNW and ORG/SiNW (without using any nitrogen precursors) devices. Finally, the hybrid NORG-30/SiNW device rapidly quantifies the alcohol content and has excellent potential for application in the food industry.