A Counter Electrode Design Based on Cu‐WSe ₂ Alloy Structure for High‐Efficiency Dye‐Sensitized Solar Cells

Dye‐sensitized solar cells (DSSCs) are attracting significant attention as alternatives to expensive semiconductor‐based solar cells due to their economical and straightforward manufacturing processes. However, initiatives are underway to substitute counter electrodes (CE) in dye‐sensitized solar cells (DSSCs), which traditionally utilize noble metal platinum (Pt). This study involved the preparation of tungsten diselenide (WSe 2 ) films using the magnetron sputtering technique, which are subsequently used as counter electrodes in a DSSCs system. Different Cu ratios are included in the WSe 2 films to enhance electron conductivity and the bonding strength between the active material and substrate. Owing to its good electrochemical properties and superior surface area, the device utilizing Cu‐WSe 2 CE delivers a power conversion efficiency (PCE) of 5.54%, exhibiting improved photovoltaic parameter metrics, thereby competing with Pt (6.22%). This study elucidated the synergistic interaction between WSe 2 ‐based CEs and electrolytes, which is crucial for achieving enhanced electrocatalytic activity in the iodide redox process. Consequently, we believe in providing this material as a viable alternative to improve energy conversion in future industrial applications.