Controlled Synthesis and Catalytic Performance of Ag₃PO₄ Polyhedra Photocatalysts

Abstract

Ag3PO4 is an effective green photocatalyst that exhibits higher visible light photocatalytic performance for the degradation of various organic pollutants. The photocatalytic performance of Ag3PO4 is affected by the exposed high‐energy crystal facets. Herein, Ag3PO4 with different morphologies and specific surfaces is synthesized via a direct precipitation method in the presence of triethanolamine (TEA). The Ag(TEA)n complex, which served as an intermediate medium, plays a critical role during the morphological transformation. When the molar ratio of Ag+ to TEA is set as 1:12, 18‐facet polyhedral morphology of Ag3PO4 crystals is obtained. The spherical and dodecahedral samples are also obtained by adjusting the molar ratio of Ag+ to TEA as 1:1 and 1:14. The photocatalytic activity of the samples for the degradation of methylene blue (MB) is tested under visible light irradiation. It is demonstrated when the molar ratio of Ag+/TEA is 1:12, Ag3PO4 polyhedra with 18‐facet are fabricated. X‐ray diffraction and scanning electron microscopy results indicate that the 18‐facet polyhedron, with six {100} facets and twelve {110} facets, enjoys the most exposed high‐energy crystal facets. Photocatalytic experiments show that the 18‐facet polyhedron has the best performance, and the degradation of MB by Ag3PO4 polyhedron with 18‐facet morphology reaches 90% within 70 min.