Micro-wheels composed of self-assembled tungsten oxide nanorods supported platinum counter electrode for highly efficient liquid-junction photovoltaic devices

•Plasma technology is introduced to synthesize Pt/WO3.•Pt nanocrystals are homogeneously distributed on the WO3 surface.•The Pt/WO3 nanohybrid processed high catalytic activity.•Dye-sensitized solar cells fabricated with Pt/WO3 shows 8.10% efficiency. In this study, the synthesis of micro-wheels composed of self-assembled tungsten oxide nanorods supported platinum (WO3/Pt) by atmospheric plasma reduction and its application in a counter electrode (CE) for highly efficient dye-sensitized solar cells were discussed. To characterize the developed materials, we conducted SEM, TEM, EDS-TEM, XRD. Due to a large surface-active area of developed material and its support for Pt nanoparticles in diameters of 2–3 nm, the WO3/Pt electrode indicated as a greater electrochemical catalyst for the redox reaction than Pt and WO3 CEs. Thus, the power conversion efficiency for a device with WO3/Pt electrode is improved to 8.10%, compared to 4.36% for a device with WO3 electrode and 7.61% for a cell with a Pt electrode. This study also supplies a procedure for fabricating highly catalytic and low-price catalyst materials for CEs, which has a tremendous meaning for various applications of micro-wheels consisted of self-assembled WO3 nanorods integrated with platinum.