Highly-efficient degradation of organic pollutants and synchronous electricity generation in a photocatalytic fuel cell based on the catalytic reactions of hydroxyl and chlorine radicals

Organic compounds in wastewater are significant energy sources. Given this situation, a novel and high performance photocatalytic fuel cell (PFC) integrated with NaOCl/Cu (II) was successfully constructed to effectively convert hazardous organics into clean energy. This designed system is comprised of nickel oxide (NiO)/TiO2 nanotubes (TNTs) photoanode and polyaniline (PANI)/multi-walled carbon nanotubes (MWCNTs) cathode. Compared to the single PFC, the combined system exhibited better performance. This coupled PFC/NaOCl/Cu (II) system enhanced the photocatalytic reaction and strengthened the re action range of reactive species from the surface of electrodes to the whole liquid phase via generation of reactive chlorine radicals (Cl-center dot, Cl-2(center dot-), ClO center dot) and reactive oxygen species (HO center dot, O-center dot(2)-, HO2 center dot). Hence, PFC/NaOCl/Cu (II) exhibited excellent cell efficiency, increasing the AB113 degradation by 48.1% and electrical power generation by 59.38% compared to the PFC system without adding NaOCl/Cu (II). The effects of the important operating parameters (initial pH, NaOCl/Cu (II), and concentration of substrate) on the PFC performance were investigated by response surface methodology (RSM). The results showed that the different model com pounds could be used as fuel. The highest short circuit current density of 3.1 mA cm(-2) , and maximum power density of 1.12 mW cm(-2) were obtained using citric acid as the substrate. This study provided an efficient approach to dispose of organic waste and to generate synchronous electrical power. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

A novel and high performance photocatalytic fuel cell integrated with NaOCl/Cu (II) was successfully constructed to convert hazardous organics into clean energy. The efficiency and power generation capability of this system outperformed traditional systems. Adjusting important operating parameters could enhance system performance, providing an efficient approach for waste disposal and power generation.