CuO embedded silica nanoparticles for tungsten oxidation via a heterogeneous Fenton-like reaction

Abstract

The Fenton reaction is used for the oxidation of tungsten via the production of hydroxyl radicals under acidic conditions. However, the narrow working pH range required for ideal reaction conditions limits the applications of these reactions. Herein, we developed a simple heterogeneous Fenton-like system for hydroxyl radical production over a broad pH range. Copper oxide nanoparticles (NPs) grown on the surface of silica NPs led to a heterogeneous Fenton-like reaction with hydrogen peroxide (H2O2), resulting in a high production rate of hydroxyl radicals in the range of acidic to neutral pH. The increased hydroxyl radical production rate at these pH values led to a high oxidation rate of tungsten. Furthermore, we applied this heterogeneous Fenton-like system to tungsten chemical mechanical planarization, resulting in high performance tungsten removal in acidic to neutral pH conditions.