A novel Trombe wall with photo-thermal synergistically catalytic purification blinds: Material and experimental performance study

Trombe wall is a widely used solar heating structure, but still has problems of easy accumulation of indoor pollutants and overheating. The photo-thermal catalytic purification technology can use solar full spectrum for air purification and heating. Thus, a Trombe wall with photo-thermal synergistically catalytic blinds was proposed, which realized heating and formaldehyde purification in winter and shading in summer. Firstly, the photo-thermal composite catalysts with different photo/thermal catalyst ratios were prepared and the formaldehyde degradation under different catalytic conditions was conducted. Then an experimental test system was built to explore the thermal and formaldehyde degradation performance under three blind turning angles of 15°, 45° and 75°. The results were: (1) The formaldehyde degradation performance was the best when the ratio of photo-thermal catalyst was 10%. (2) The solar radiation reduced the activation energy of photo-thermal catalysts by 14.5%–31.3%, which revealed a photo-thermal synergistic catalytic effect. (3) Indoor steady experiments showed that the comprehensive performance of wall increased with the solar radiation intensity and blind angle. (4) The outdoor experiments showed the wall behaved best performance when the blind turning angle was 45°. The thermal efficiency and total generated clean air could reach 40.9% and 205.1 m3 at daytime, respectively.