Investigating the potential of CuSCN as hole transport layer for perovskite solar cells for applications in indoor photovoltaics

Abstract

Indoor photovoltaics (IPV) has recently emerged as a sustainable and reliable energy technology to power the rapidly growing Internet of Things. Among various solar cell technologies, emerging perovskite solar cells (PSCs) have gained great interest for IPV; owing to their unique optoelectronic properties such as bandgap tunability to efficiently harvest the indoor light spectrum. The choice of hole transport layer (HTL) is critical for efficient PSCs, particularly in IPV applications to reduce the parasitic absorption losses in the indoor light spectrum. Here, we explore the potential of CuSCN to be used as a HTL for PSCs in IPV applications. We show that CuSCN-based PSC exhibits remarkable power conversion efficiency (η) as compared to PSCs using conventional PEDOT:PSS as HTL. We explore the effects of wavelength (λ) of incident photons and various design parameters of PSC for optimal cell operations. We show that at a particular perovskite thickness, CuSCN-based PSC exhibits ∼8%–12% higher η than that for PEDOT-based PSC, for all λ in the visible range of the spectrum. We further explore the effect of HTL doping/thickness on PSC performance and show that CuSCN-based PSC performs optimally for a wide range of doping/thickness of HTL. We also find that CuSCN-based PSC outperforms PEDOT-based PSC for a broad range of incident irradiance. Finally, we show that for large values of λ (i.e. λ = 700 nm), η exceeds 30%, close to the highest ever in the past work. The work presented in this study will provide guidance for the development of efficient PSCs for indoor applications.