Development of a novel graphitic carbon nitride and multiwall carbon nanotube co-doped Ti/PbO2 anode for electrocatalytic degradation of acetaminophen

Abstract

In this work, we have constructed a novel graphitic carbon nitride/multiwall carbon nanotube (GCN/CNT) doped Ti/PbO2 as anode for highly effective degradation of acetaminophen (ACE) wastewater. The ACE removal efficiency of 83.2% and chemical oxygen demand removal efficiency of 76.3% are achieved under the optimal condition of temperature 25 °C, initial pH 7, current density 15 mA cm−2 and Na2SO4 concentration 6.0 g L−1. The excellent electrocatalytic activity of Ti/PbO2-GCN-CNT anode for ACE oxidation is ascribed to the effective suppression of oxygen evolution and the enhanced electron transfer after introducing GCN and CNT. Furthermore, Ti/PbO2-GCN-CNT electrode displays excellent stability and reusability. ACE degradation is accomplished by direct oxidation and indirect oxidation, and ∙OH radical plays primary role in the indirect oxidation of ACE wastewater. The intermediates of ACE degradation are detailly investigated using LC-MS analysis and a possible degradation mechanism is proposed.