The Strengthened Photocatalytic NO(x) Removal of Composites Bi(4)O(5)Br(2)/BiPO(4): The Efficient Regulation of Interface Carriers by Integrating a Wide-Bandgap Ornament

A series of binary composites Bi(4)O(5)Br(2)/BiPO(4) (PBX) was fabricated through a simple mechanical ball milling protocol. Relevant microstructural, morphological, and optical properties were thoroughly analyzed via various techniques. The integration of both components was confirmed to produce heterojunction domains at the phase boundaries. Upon exposure to visible light irradiation, the as-achieved PBX series possessed the reinforced photocatalytic NO(x) removal efficiencies and the weakened generation of toxic intermediate NO(2) in comparison to both bare components, chiefly attributed to the efficient transport and separation of carriers and boosted production of superoxide radicals (·O(2)(−)) through the combination of a wide-bandgap ornament BiPO(4) as an electron acceptor. In particular, the composite PB5 with the optimal phase composition exhibited the highest NO(x) removal of 40% with the lowest NO(2) formation of 40 ppb among all tested candidates. According to the band structures’ estimation and reactive species’ detection, a reasonable mechanism was ultimately proposed to describe the migration of charge carriers and the enhancement of photocatalytic performance.