• Bhandari, Shubhranshu
• Sadhukhan, Priyabrata
• Sundaram, Senthilarasu
• Das, Sachindranath
• Mallick, Tapas K.
• Roy, Anurag

Abstract

One of the features of perovskite solar cells (PSCs) that make them stand out among all photovoltaics (PVs) is their high open-circuit voltage (VOC). Owing to their simple manufacturing process, low cost of components, and good stability, carbon electrode-based metal-halide PSCs are gaining interest for their better stability and low cost than noble metal electrodes. However, carbon electrode-based hybrid PSCs suffer low open-circuit voltage (VOC). This work demonstrated the fabrication of ambient processed hybrid perovskite solar cells using low-temperature curable carbon-based electrodes without a hole transport layer. The devices exhibit an impressive high open circuit voltage of 1.07 V, even without a dedicated hole transport layer. The photovoltaic performance was further investigated with the same perovskite absorber, synthesized by solution-processed and solid-state synthesis routes. The latter have yielded better short circuit current and power conversion efficiency due to perovskite's lesser built-in trap density. Furthermore, using a combined ionic electronic carrier transport model, an electric double-layer formation was ensured across the perovskite/carbon interface and accumulating halide vacancies at the perovskite/TiO2 interface can effectively reduce carrier recombination and boost the device's VOC. This study envisages the impact of the electric double layer in free carrier transport of an ionic-electronic semiconductor like hybrid perovskites and can pave the way to improve the open-circuit voltage of carbon-based perovskite solar cells.<br/><br/>

Topics

• density
• perovskite
• impedance spectroscopy
• Carbon
• semiconductor
• power conversion efficiency