Building a lunar human base is one of the important goals of human lunar exploration. This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temperature carbon dioxide electrolysis, utilizing the full solar spectrum. The optimal oxygen production rates under different solid oxide electrolysis cell inlet temperatures
T_\mathrme 
, ultraviolet (UV) separation wavelengths
\lambda _2 
, infrared (IR) separation wavelengths
\lambda _3 
, and photovoltaic cell materials were explored. The results indicate that the inlet temperature of the solid oxide electrolysis cell should be as high as possible so that more carbon dioxide can be converted into carbon monoxide and oxygen. Furthermore, when the ultraviolet separation wavelength is approximately 385 nm, the proportion of solar energy allocated to the photoreaction and electrolysis cell is optimal, and the oxygen production rate is highest at 2.754×10
−4 mol/s. Moreover, the infrared separation wavelength should be increased as much as possible within the allowable range to increase the amount of solar radiation allocated to the electrolysis cell to improve the rate of oxygen generation. In addition, copper indium gallium selenide (CIGS) has a relatively large separation wavelength, which can result in a high oxygen production rate of 3.560×10
−4 mol/s. The proposed integrated oxygen production method can provide a feasible solution for supplying oxygen to a lunar human base.