PtCoFe Nanowire Cathodes Boost Short-Circuit Currents of Ru(II)-Based Dye-Sensitized Solar Cells to a Power Conversion Efficiency of 12.29%

PtCoFe nanowires with different alloying compositions are chemically prepared and acted as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs) with Ru(II)-based dyes. Due to their superior I-3(-) reduction activity, PtCoFe nanowires with rich (111) facets enhance the performance of DSSCs. Hence, N719 DSSCs with PtCoFe nanowires, respectively, produce better power conversion efficiency (PCE) of 8.10% for Pt33Co24Fe43 nanowire, 8.33% for Pt74Co12Fe14 nanowire, and 9.26% for Pt49Co23Fe28 nanowire in comparison to the PCE of Pt CE (7.32%). Further, the PRT-22 DSSC with Pt49Co23Fe28 nanowire exhibits a maximum PCE of 12.29% with a certificated value of 12.0%, which surpass the previous PCE record of the DSSCs with Ru(II)-based dyes. The photovoltaic and electrochemical results reveal the composition-dependent activity along with a volcano-shaped trend in the I-/I(3)(-)redox reaction. Theoretical work on the adsorption energies of I-2, the desorption energies of I-, and the corresponding absolute energy demonstrates that the I-3(-) reduction activity followed in the order of Pt49Co23Fe28(111) plane > Pt74Co12Fe14(111) plane > Pt33Co24Fe43(111) plane, proving Pt49Co23Fe28 nanowire to be a superior cathode material for DSSCs.