Optimization of tribocatalytic performance by modifying the concentration of oxygen vacancies in KSr ₂ Nb ₄ TaO ₁₅ ceramics

Abstract In recent years, catalytic degradation driven by mechanical‐energy tribocatalysis has gained much attention. Point defects play very important on the catalytic activity of ferroelectric oxides. In this study, we focus on the influence of oxygen vacancies on the catalyst performance of ferroelectric oxide KSr 2 Nb 4 TaO 15 (KSNT) with a tetragonal tungsten bronze structure. The concentration of oxygen vacancies is modified by sintering atmosphere. The KSNT sintered in N 2 atmosphere exhibits the best tribocatalytic degradation efficiency of 96.7% within 2 h for degradation rhodamine B due to high concentration of oxygen vacancies. The excellent degradation efficiency is attributed to the defect energy level of KSNT and high electron–hole separation efficiency. This work reveals the relationship between oxygen vacancies and tribocatalysis efficiency, which is helpful to design and modify the new ferroelectric oxides for tribocatalysis.