Improved hole transport in inverted perovskite solar cells with carbon nanorings

Abstract

The photovoltaic performances of inverted-planar organo-lead halide perovskite solar cells (PSCs) largely depend on the efficient charge transport layer. Here we design carbon nanorings (CNRs) to provide efficient carrier transport and suppress nonradiative recombination losses at the interface. The obtained CNRs have a diameter of ∼300 nm and a length of 100–300 nm. Inverted-planar organo-lead halide PSC devices based on a novel hybrid hole-transport layer (HTL) consisting of CNRs and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT : PSS) show a device efficiency of 23.16%. We demonstrate that CNRs can provide a direct channel for hole transfer, which could reinforce selective hole extraction and transfer, and might alleviate undesirable charge accumulation at PEDOT : PSS/perovskite interfaces. The special structures of CNRs may have potential applications in perovskite photovoltaic devices.