Understanding the electrocatalytic behaviours of counter electrode (CE) electrocatalysts favors to tune the sluggish triiodide (I-3) reduction kinetics and to compare their catalytic activities. We present here the experimental realization of cost-effective CE electrocatalysts from urchin-like NiM (M = Pt, Ru, Pd) for studying the profounding charge transfer processes without sacrificing photovoltaic performances of DSSCs. Our focus is placed on the systematic studies of catalytic activities along with modeling of I3 reduction reaction rate constant, extracting k = 4 pi Dr(a)N(B) for zero-dimensional electrocatalysts. The DSSCs yield conversion efficiencies of 9.08%, 7.74%, and 6.86% with NiPt, NiRu, and NiPd CEs, respectively. (C) 2015 Elsevier Ltd. All rights reserved.