Impacts of plasmonic nanoparticles incorporation and interface energy alignment for highly efficient carbon-based...

This work utilizes a realistic electro-optical coupled simulation to study the (i) impact of mesoporous TiO₂ removal; (ii) the embedding of Ag@SiO₂ and SiO₂@Ag@SiO₂ plasmonic nanoparticles; (iii) utilization of solution-processed inorganic p-type copper(I) thiocyanate (CuSCN) layer at the perovskite/carbon interface; and (iv) the increase of the work function of carbon electrodes (via incorporation of suitable additives/binders to the carbon ink) on the performance of carbon-based PSCs. Removal of mesoporous TiO₂ increased the power conversion efficiency (PCE) of the device from 14.83 to 16.50% due to the increase in exciton generation rate and charge carriers' mobility in the vicinity of the perovskite-compact TiO₂ interface. Subsequently, variable mass ratios of Ag@SiO₂ and SiO₂@Ag@SiO₂ plasmonic nanoparticles are embedded in the vicinity of the perovskite-compact TiO₂ interface. In the optimum cases, the PCE of the devices increased to 19.72% and 18.92%, respectively, due to light trapping, scattering, and strong plasmonic fields produced by the plasmonic nanoparticles. Furthermore, adding the CuSCN layer remarkably increased the PCE of the device with a 0.93% mass ratio of Ag@SiO₂ nanoparticles from 19.72 to 26.58% by a significant improvement of V_oc and FF, due to the proper interfacial energy band alignment and the reduction of the recombination current density. Similar results were obtained by increasing the carbon work function, and the cell PCE was enhanced up to 26% in the optimal scenario. Our results pave the way to achieve high efficiencies in remarkably stable printable carbon-based PSCs.