A class of alloyed Pd-Co catalysts are prepared by a mild solution method and subsequently blended with poly(vinylidene fluoride) (PVDF) binder for coating cost-effective counter electrodes (CEs) of dye-sensitized solar cells (DSSCs). The electrocatalytic activity for the redox electrolyte as well as photovoltaic performances of DSSCs are optimized by adjusting stoichiometric Pd/Co ratios. Due to the merits of resultant Pd-Co alloy CEs on good electrical conduction, rapid charge-transfer ability, and increased electrocatalytic activity, a maximum conversion efficiency of 6.44% is determined on the optimized DSSCs in comparable to 6.18% for Pt CE based DSSC. It is obvious that Pd-Co alloy CEs can be a better cost-effective and efficient alternative due to the expensive price and scarcity of Pt for the large scale applications of DSSCs. (C) 2015 Elsevier Ltd. All rights reserved.