Nitrogen-doped carbon aerogel supported SnO2 anode for electrocatalytic degradation of phenol: Enhanced generation of free radicals

To obtain a high-efficiency and low-cost electrocatalytic anode for environmental pollutant degradation, a nitrogen doped graphene aerogel supported tin oxide (SnO 2 -NGA) composite catalyst was prepared and SnO 2 -NGA/Ti anode was fabricated. The influence of nitrogen doping content on electrocatalytic activity of the catalysts was investigated. The effects of current density and initial solution pH on degradation efficiency were studied. The SnO 2 -N 3.0 GA/Ti anode shows good catalytic activity for phenol degradation. The conversion of phenol and COD removal by SnO 2 -N 3.0 GA/Ti reached 83.6% and 61.2% within 4 h when applied current density was 5.00 mA/cm 2 and initial pH was 3.0. The SnO 2 -N 3.0 GA/Ti electrode has higher specific surface area, and lower charge transfer resistance. The nitrogen atoms doping increased the content of pyridinic N species, which is beneficial for providing more in-situ catalytic active sites and enhancing the production of reactive oxygen species, especially hydroxyl radical (•OH). This work provides a novel strategy for synthesis of electrocatalytic anode with enhanced activity for degradation of refractory organic pollutants in water.