Effect of Cuprous Oxide Nanocubes and Antimony Nanorods on the Performance of Silicon Nanowire-Based Quasi-Solid-State Solar Cell.

Abstract

Antimony nanorods (SbNRs) anchored to vertically aligned SiNWs serve as cosensitizers and enhance the light absorption of NWs, and their favorably positioned valence band (VB) coupled with their p-type semiconducting nature allows fast hole extraction from SiNWs. Photocorrosion of SiNWs is effectively prevented by a monolayer of N-[3-(trimethoxysilyl)propyl]aniline (TMSPA). Upon assembling a quasi-solid-state solar cell with a SbNRs@TMSPA@SiNW photoanode, a triiodide-iodide (I3 -/I-) redox couple-based gel encompassing dispersed p-type cuprous oxide nanocubes (Cu2O NCs) as the hole transport material. and an electrocatalytic NiO as the counter electrode, a power conversion efficiency (PCE) of 4.7% (under 1 sun) is achieved, which is greater by 177% relative to an analogous cell devoid of the Cu2O NCs and SbNRs. SbNRs at the photoanode maximize charge separation and suppress electron-hole and electron-I3 - recombination at the photoanode/electrolyte interface, thereby improving the overall current collection efficiency. Concurrently, the Cu2O NCs facilitate hole scavenging from SbNRs or SiNWs and relay them rapidly to the I- ions in the electrolyte. Optically transparent and mesoporous NiO with a VB conducive to accepting electrons from FTO permits abundant interaction with I3 - ions. The high PCE is a cumulative outcome of the synergistic attributes of SbNRs, Cu2O NCs, and NiO. The SbNRs@TMSPA@SiNWs/Cu2O-gel/NiO solar cell also exhibits a noteworthy operational stability, for it endures 500 h of continuous 1 sun illumination accompanied by an ∼24.4% drop in its PCE. The solar cell architecture in view of the judiciously chosen components with favorable energy level offsets, semiconducting/photoactive properties, and remarkable stability opens up pathways to adapt these materials to other solar cells as well.