BiVO4 is an important n-type semiconductor used in photocatalysis due to its high capacity to absorb solar light in the 400–700 nm range, abundance, high chemical stability, non-toxicity, and low cost. However, research on physicochemical modifications to increase its catalytic activity via simple procedures is limited. In this work, the influence of different synthesis parameters, such as calcination temperatures or silver doping, on the structural and physicochemical characteristic of the BiVO4-based photocatalysts and their photocatalytic performance in degrading sulfamethoxazole from aqueous solution under blue-LED irradiation was evaluated. BiVO4-based photocatalysts were synthesized using a solvothermal method. The monoclinic phase (m-s) was successfully kept stable even after the thermal treatments at 300, 450, and 600 °C and the corresponding silver doping. The low bandgap of 2.40 eV and the average particle size of 18 nm of the BiVO4 catalyst treated at 300 °C seems to be the key. Afte doping, Ag/BiVO4 photocatalyst treated at the optimal found calcination temperature (300 °C) showed the best photocatalytic behavior.