Integrating an Ag0-Ag+ mediated Ag2Ta4O11/Ag8(Nb0.5Ta0.5)26O69 heterojunction to quickly decontaminate indoor gaseous formaldehyde under indoor temperature, humidity and sunlight irradiation conditions

Formaldehyde (HCHO) is the primary pollutant indoors, and thus it is essential to establish a feasible proposal to decontaminate HCHO to an acceptable level in terms of human health. Here, using doping andin situlight reduction, a cation vacancy-rich Ag2Ta4O11/Ag-8(Nb0.5Ta0.5)(26)O(69)heterojunction is carefully prepared with Ag nanoparticles as cocatalyst. The prepared material is used to photodegrade gaseous HCHO under completely simulated indoor conditions, presenting 100% conversion for 200 ppm and 85.5% for 1600 ppm HCHO under 7 h of sunlight irradiation. Its long-term effectiveness and speed of use were confirmed with six recycling tests under a long 42 h period of sunlight illumination and activity evaluation over a six-month period. Meanwhile, environmental factor estimation confirms its superior CO(2)selectivity (99.90%) and humidity resistance. These good performances are ascribed to the Ag-0-Ag(+)redox electron pairs producedin situ, Nb doping, various interfacial phase interactions and lots of Ag-deficiencies, which contribute to excellent solar light harvesting, quick separation of electron-hole pairs, strong adsorption towards reactive HCHO, maintenance of strong redox ability, and little shedding or aggregation. Consequently, the present sample could be very promising as a long-lasting material for the removal of indoor HCHO.