Performances Of Mnwo4@Ac Mixed Oxide Composite Materials As Pt-Free Counter Electrodes For High Efficiently Dye Sensitized Solar Cells

Replacing the expensive Pt catalyst of counter electrodes (CEs) with a low-cost Pt-free catalyst has been regarded as one of the crucial steps for cost effectiveness of dye-sensitized solar cells (DSSCs). Herein, MnWO4 as a binary mixed oxide (MnO-WO3) has been prepared with (NH4)(10)H-2(W2O7)(6)center dot xH(2)O and Mn(NO3)(2)center dot 4H(2)O via a facile hydrothermal method. DSSCs using MnWO4 CEs show power conversion efficiency (PCE) of 4.93%. To improve the catalytic activity of MnWO4 CEs further, three proportions of MnWO4@AC mixed oxide composite catalysts have been fabricated via simple physical mixing MnWO4 with activated carbon (AC) by ball-milling. Moreover, the DSSCs with the MnWO4@AC composites CEs generate high PCE of 6.50, 6.45 and 6.12%, respectively, from MnWO4 : AC mass ratios of 1 : 2, 1 : 1 and 2 : 1 for the regeneration of traditional iodide/triiodide (I-3(-)/I-) redox couples, which were superior to the pristine MnWO4, Pt- and AC-based counterpart 4.93%, 4.54% and 2.10% CEs under the same test conditions and method. The favorable performances make MnWO4@AC composites act as a new resource of electro-catalytic Pt-free materials for high-performance CEs in the encapsulation of DSSCs.