This article proposes a novel hybrid solar gradient utilization photocatalytic-thermal-catalytic-Trombe (PTC-Trombe) wall, which can realize dual functions of air purification and space heating. Firstly, based on the previous studies on photocatalytic-Trombe (PC-Trombe) and thermal-catalytic-Trombe (TC-Trombe) walls, a thermal and mass model of FTC-Trombe wall is established. Secondly, the performance comparisons among three Trombe walls are conducted based on the experimental results in daytime. Thirdly, the effect of solar radiation intensity on the system performance of PTC-Trombe wall is discussed. Finally, the energy saving performance of three walls in Hefei is calculated. Results are: (1) PTC-Trombe wall behaves the best performance for formaldehyde degradation compared with other walls; (2) The effect of solar radiation intensity on the catalytic oxidation rate in PTC-Trombe wall can be divided into three regions with different catalytic oxidation mechanisms; (3) The total reduced heat loads for PC-Trombe wall, TC-Trombe wall and PTC-Trombe wall are 309.8, 204.7 and 296.1 MJ/m(2), while the total generated volume of clean air is 4764.9, 6608.9 and 9482.2 m(3)/m(2), respectively. (C) 2019 Elsevier Ltd. All rights reserved.