A novel ZnMn2O4/g-C3N4 nanocomposites heterojunction photocatalyst: preparation, characterization, and investigation of photocatalytic behavior over toxic dyes
Masoumeh Yaqoubi, Mojgan Ghanbari, Masoud Salavati-Niasari, Forat H. Alsultany, Salman Khalaf Issa
Abstract
Spinel-type photocatalysts, e.g., ZnMn 2 O 4 , have been receiving intense interest owing to their high photochemical stability and visible light absorption. However, their photocatalytic activity is limited due to fast electron–hole recombination. In this work, we present the preparation of a new ZnMn 2 O 4 /g-C 3 N 4 nanocomposite heterojunction photocatalyst by a simple ultrasonic technique to solve this disadvantage. With the tuning of ZnMn 2 O 4 loading, the optimal loading for 10% ZnMn 2 O 4 /g-C 3 N 4 nanocomposite presented excellent dye removal efficiency of 98.8% under visible light irradiation, which strong outperformed pristine g-C 3 N 4 and ZnMn 2 O 4 by 33.7% and 43.0%, respectively. Radical scavenging studies indicated that hydroxyl radical (·OH) was primarily involved in the degradation mechanism. The kinetic study also supported the high reaction rate constant ( k = 0.0333 min ‒1 ). This work presents a promising route to develop efficient, recyclable, stable, and visible light-driven photocatalysts for wastewater treatment.