Degradation of gaseous HCHO in a rotating photocatalytic fuel cell system with an absorption efficiency of up to 94

Abstract Removing gaseous formaldehyde (HCHO) using photocatalyst oxidation is of great interest. Herein, a photocatalytic fuel cell (PFC) with a rotating photoanode was proposed for gaseous HCHO degradation with the features of efficient absorption, fast oxidation and humidity less sensitivity. The results indicated that the as-fabricated rotating PFC system can facilitate the absorption of gaseous HCHO (up to 94.0%) in the thin liquid film formed on the upper anode surface, and have an efficient separation of the photoinduced electron-hole pairs on the TiO2 photoanode. Within this context, the rotating PFC showed a superior HCHO degradation efficiency of 82.4%, which was 3.6 times higher than that of the conventional gaseous HCHO degradation. In addition, the rotating PFC exhibited a high stability under different relative humidity, an effective power generation and an excellent reproducibility for HCHO degradation. For the proof-of-concept presented here, a new type of liquid-film air purifier was designed and a good gaseous HCHO purification was obtained. Therefore, the rotating PFC system has a great promising application in gaseous HCHO removal and simultaneous energy recovery.