<p>2D transition metal carbides, nitrides, and carbonitrides (MXenes) have excellent characteristics, which make them a promising group of materials for many applications, including energy harvesting, energy storage, electrocatalysis, water purification, medicine, and electromagnetic interference shielding. This work has, for the first time, investigated the optical and power factor of Ti₃C₂T_x MXene films, which are prepared using the spin coating method with different concentrations (5%, 10%, 15%, and 20%) in dimethyl sulfoxide (DMSO). We use a simple strategy of different concentrations to optimize the performance of the Ti₃C₂T_x semiconductor for thermoelectric energy conversion. The etched Ti₃C₂T_x MXene films were investigated by the X-ray diffraction phase analysis. The elementary lattice parameter (c), lattice volume, and crystallite size decrease as the concentrations increase. The optical bandgap of the Ti₃C₂T_x MXene films changes from 0.990 eV to 0.951 eV. In the range from 325 to 550 K, the power factor of Ti₃C₂T_x Mxene film with 15% concentration exhibits the highest values and varies from about 5 × 10^–1 to 1 × 10^–7 W/mK². Moreover, the prepared Ti₃C₂T_x MXene film with 15% concentration showed the highest electrical conductivity, enhanced the Seebeck coefficient, and achieved the highest power factor. This work presents strong evidence and practical reference for enhancing and optimizing the thermoelectric characteristics of Ti₃C₂T_x MXene film.</p>