US 2025/0122102 A1 · BIAS-FREE DRIVEN ION ASSISTED PHOTOELECTROCHEMICAL WASTEWATER TREATMENT SYSTEM AND METHOD

Abstract

A bias-free driven ion-based photoelectrochemical wastewater treatment system and method is disclosed. Through an ion-coupled photogenerated electron-assisted photocatalytic oxidation-reduction pathway, the system achieves efficient treatment of high-salinity wastewater. The system employs electron-ion receptor materials as the counter electrode, providing reaction sites to drive the coupling of photogenerated electrons and cation transfer. Additionally, the voltage generated by the system directly drives hole oxidation to produce strong oxidizing free radicals. Furthermore, this ion-based photoelectrochemical system demonstrates excellent degradation performance in high-concentration chloride media. This indicates that, in addition to cations (such as Na+) helping to accelerate the electron transfer rate, the presence of Cl− further enables efficient and sustainable wastewater treatment. The concept proposed in this invention emphasizes the potential for using abundant sodium chloride in seawater as an inexpensive additive for wastewater treatment.

Claims10

Dependent claims

A bias-free driven ion-based photoelectrochemical wastewater treatment system, comprising a photoanode, a cathode, a quartz electrolytic cell containing an electrolyte, and a xenon lamp light source simulating the solar spectrum;

the photoanode is an electrode made of an oxygen vacancies-enriched N-type semiconductor, and the cathode is an electrode made of an electron-ion receptor material;
the photoanode and cathode are inserted at both ends of the quartz electrolytic cell, and an external circuit wire is provided between the photoanode and cathode;
when illuminated, the photoanode is excited by the simulated light source from the xenon lamp to generate electron-hole pairs;
the cathode made of electron-ion receptor material has the function of simultaneously receiving coupled electrons and ions;
photogenerated electrons quickly flow to the cathode via the external circuit while coupling with cations in the electrolyte to achieve the transfer of photogenerated electrons.

2 more elements

A method for bias-free driven ion-based photoelectrochemical wastewater treatment, comprising the following steps:

(1) selection and preparation of a photoanode:
selecting an oxygen vacancies-enriched N-type semiconductor and preparing a photoelectrode made of the oxygen vacancies-enriched N-type semiconductor via a hydrothermal or electroplating method;
(2) selection and preparation of a cathode:
selecting a material that has the function of simultaneously embedding ions and electrons, and preparing the cathode made of electron-ion receptor material by spin coating;
(3) installation of a reaction device:
inserting the photoanode and cathode into two ends of a quartz electrolytic cell containing an electrolyte, where the quartz electrolytic cell holds organic wastewater;
providing an external circuit wire between the photoanode and cathode to form the reaction device.
(4) perform photoelectrochemical reaction using the reaction device:
illuminating the photoanode with the xenon lamp light source simulating the solar spectrum;
the simulated light source from the xenon lamp excites the generation of electron-hole pairs;
the cathode, made of electron-ion receptor material, simultaneously receives coupled electrons and ions;
photogenerated electrons quickly flow to the cathode through the external circuit while coupling with cations in the electrolyte to transfer photogenerated electrons;
the holes left on the photoanode undergo water oxidation to form strong oxidizing agents (·OH);
then reacting with chloride ions to form free chlorine, which is oxidized by h+, ·OH, or ·Cl to form ·CIO, thereby oxidizing and mineralizing organic pollutants in the wastewater.

11 more elements

Dependencies are inferred from the claim text.

Bias-free driven ion assisted photoelectrochemical wastewater treatment system and method

Life of this patent

Bias-free driven ion assisted photoelectrochemical wastewater treatment system and method

Life of this patent

Abstract

Claims10