Controlled Synthesis and Catalytic Performance of Ag₃PO₄ Polyhedra Photocatalysts

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.