Mitigation of Exciton Quenching Sites in All-Metal-Oxide-Based Transparent Photovoltaic

Abstract

Transparent photovoltaic (TPV) devices offer the potential to generate power without being visible to the human eye, making them ideal for use in building integrated photovoltaic applications. TPV devices based on inorganic materials offer eco-friendly frameworks with stable performances. However, their low power conversion efficiency and incapacity to produce onsite power for real-time practical applications limit their widespread deployment. Mitigation of exciton quenching by reducing the interface and bulk recombination can significantly improve the performance of TPVs. To address this, the present study investigates the effect of passivation layers (PLs) in all-metal-oxide TiO2/Cu2O TPV. The TiO2/Cu2O TPV interface is passivated by depositing thin Al2O3 and Ga2O3 films. The study comprehensively analyzes how passivation controls the interfacial and bulk defects. Electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy are used to elucidate exciton quenching mechanisms. The results show that the insertion of a thin PL on top of TiO2 effectively mitigates exciton quenching by suppressing hydroxyl ions, Ti2+, and Ti3+ bulk states. Ga2O3 PL, in particular, leads to a substantial enhancement in short-circuit current density (12.4 mA cm(-2)) and open-circuit voltage (669 mV). The study also demonstrates the real-time onsite energy production and its utilization through the operation of an electric fan. A thin layer of Ga2O3 passivates the interface of TiO2/Cu2O transparent photovoltaic (TPV) and mitigates the exciton quenching sites. The Ga2O3 passivation layer assists the TPV to exhibit high photovoltaic performance without deteriorating its optical transparency. Onsite power production by TPV is sufficient to operate a mini fan of milliwatt power.image (c) 2024 WILEY-VCH GmbH