Improved Nanophotonic Front Contact Design for High-Performance Perovskite Single-Junction and Perovskite/Perovskite Tandem Solar Cells

The front contact of solar cells greatly influences the optoelectronic performance of perovskite solar cells (PSCs) by controlling the coherent light propagation as well as charge transport within the device. Herein, the nanophotonic front contact consisting of multilayer nanodomes and nanoholes for high-efficiency perovskite single-junction and perovskite/perovskite tandem solar cells (PVK/PVK TSCs) is investigated. The optical and electrical characteristics of solar cells are investigated by conducting an advanced 3D numerical approach with the combination of finite-difference time-domain (FDTD) and finite-element method (FEM) simulations embedded with the particle swarm optimization (PSO) algorithm. The numerical modeling is validated by fabricating a set of efficient PSCs, optimized to a power conversion efficiency (PCE) of 17.9%, V-OC of 1.07 V, J(SC) of 21.8 mA cm(-2) and fill factor (FF) of 77%. The nanophotonic device results in improved J(SC) by 10-15%, resulting from 10-15% enhanced light incoupling compared with the planar device, while also strengthening the omnidirectional capabilities at angles of illumination as high as 40 degrees. The optimized nanophotonic front contact results in PCEs of >23% and >30% (matched J(SC) approximate to 18 mA cm(-2)) for single-junction PSCs and PVK/PVK TSCs, respectively. Details of the nanophotonic front contact, device, and fabrication process are provided.

Automated summary

The study focuses on investigating the nanophotonic front contact for high-efficiency perovskite solar cells, which leads to improved J(SC) and enhanced light incoupling, ultimately resulting in higher power conversion efficiency. The optimized nanophotonic front contact demonstrates potential for achieving PCEs over 23% and 30% for single-junction PSCs and PVK/PVK TSCs, respectively.