Coupled UV–Vis light photocatalysis energy driven solar gradient utilization thermoelectric power and air purification system

Efficient utilization of solar spectral gradient to meet multiple building demands is a global challenge. Photocatalysts, based on the principle that different materials respond to different parts of the light spectrum, can degrade pollutants. This study presented a coupled UV–Vis light photocatalysis energy driven solar gradient utilization thermoelectric power and air purification system (UV–Vis-PC/TEG), aiming to achieve the gradient utilization on solar energy for the electrical, heating and air purification requirements of buildings. Comparative studies of the pure TEG, UV-PC/TEG, and UV–Vis-PC/TEG systems were conducted. The result showed that in air–water heat collection mode, the UV–Vis-PC/TEG system achieved its highest overall efficiency, with thermal, electrical, and purification efficiencies of 65.3 %, 4.9 %, and 50.9 %, respectively. These correspond to increases of 21.4 %, 28.9 %, and 141.2 % relative to the UV-PC/TEG system. The heat-mass transfer model was established and the model accuracy was verified. Based on the model, numerical simulations were performed. The results showed that the average thermal efficiency, electrical efficiency, purification efficiency and comprehensive efficiency of the system were 51.5 %, 5.2 %, 52.0 % and 56.7 %, respectively. These results indicate that the system is highly efficient at utilizing solar energy and has considerable potential for energy conservation and air purification applications.