Synthesis and photocatalytic property of a new silver thiocyanate semiconductor

• A new AgSCN photocatalytic material was synthesized successfully.
• The photodegradation efficiency over AgSCN was 2.74 times that of N-TiO2.
• OH radicals were the main active species in the oxidation of RhB.

A new AgSCN photocatalytic material with a novel nonmetal acid structure was synthesized by an ion-exchange method. Its structure and properties were characterized in detail. UV–vis absorption spectrum showed that AgSCN had the optical indirect band gap of 3.51 eV. The valence level of AgSCN was determined as 1.52 eV by X-ray photoelectron spectrometer. The photodegradation efficiency of rhodamine B over AgSCN was 2.74 times that of N-doped TiO2 (N-TiO2) under UV light radiation. The photodegradation rate constant was 4.8 times that of N-TiO2. The high photocatalytic activity mainly resulted from SCN− and the high position of valence band. OH radicals, as the dominant active species in photocatalysis, primarily originated from the multi-step reduction of O2 by photogenerated electron.