Recently, much attention has focused on less platinum alternative materials serving as the counter electrode material for dye-sensitized solar cells, while platinum itself has a lot of room for improvement. Herein, we introduce the earth-abundant silicon and combine it with Pt nanoparticles as the counter electrode in dye-sensitized solar cells to enlarge surface area and enhance the activity of Pt. Si-H bonds can reduce metal ions and enable small metal nanoparticles grown on the surface of silicon nanowires, which can effectively prevent metal nanoparticles from agglomeration in the catalysis. The density functional theory (DFT) calculation shows that the adsorption energy of I atom on the Pt/Si interface is -0.8 eV, which is the optimal adsorption energy for triiodide reduction, indicating that Pt/Si is a perfect material for the counter electrode. The electrochemical characterizations and the photocurrent-voltage performance experimentally confirm that Pt/SiNW is a better counter electrode material than other metal/SiNW composites and Pt, which is in accordance with DFT calculations. The power conversion efficiency of device based on the Pt/SiNW electrode is higher than that of the device based on Pt (8.23% vs. 7.93%). (C) 2018 Elsevier Ltd. All rights reserved.