Contact electrocatalyst, method for making thereof and its applications in degrading organic pollutants

Abstract

This invention discloses a contact electrocatalyst comprising a modified PMMA polymer containing multiple functional monomers, wherein the side chains of the functional monomers are configured with electron-withdrawing groups. The plasma-modified polymer, due to the high substitution rate of the electron-withdrawing groups, can promote the generation of a large number of reactive oxygen species, which helps to improve the degradation effect of organic pollutants. It can also be recycled and repeatedly used for electrocatalytic degradation, and maintains high degradation performance even after long-term storage, thus possessing durability.

Claims

1. A contact electrocatalyst comprising a modified PMMA polymer, wherein the surface layer contains a plurality of functional monomers, wherein, The side chain of this functional monomer is configured with electron-withdrawing groups, which include carbon-oxygen bonds (CO), carbonyl groups (C=O), ester groups (-COOR), or carbon dangling bonds (C-), wherein R is a group with any number of carbon atoms, and the molecular weight of the modified PMMA polymer is 100,000 to 2,000,000.

2. The contact electrocatalyst as described in claim 1, wherein, The surface work function of this modified PMMA polymer is greater than 4.5 eV and less than or equal to 7.4 eV.

3. The contact electrocatalyst as described in claim 1, wherein: The electron-withdrawing groups include carbon dangling bonds (C-); the surface work function of the modified PMMA polymer is greater than 6.6 eV and less than or equal to 7.4 eV; the molecular weight of the modified PMMA polymer is 900,000 to 1,200,000.

4. A method for preparing a contact electrocatalyst, comprising: A PMMA polymer is subjected to plasma treatment for a certain period of time to convert the side chain groups of the structural monomers on the surface of the PMMA polymer into electron-withdrawing groups to form functional monomers, thereby obtaining a modified PMMA polymer. The electron-withdrawing groups include carbon-oxygen bonds (CO), carbonyl groups (C=O), ester groups (-COOR), or carbon dangling bonds (C-), where R is a group with any number of carbon atoms.

5. The preparation method as described in claim 4, wherein, The plasma treatment includes bombarding the PMMA polymer with a plasma of 200 to 4000 watts in a plasma gas atmosphere for a time of 10 to 300 seconds, wherein the plasma gas atmosphere contains helium, argon, neon, nitrogen, or air.

6. The preparation method as described in claim 4, wherein, The plasma treatment uses a plasma source including one or more of capacitively coupled plasma, inductively coupled plasma, pulsed discharge plasma, hot wire, electron cyclotron resonance plasma, or atmospheric pressure plasma.

7. A method for degrading organic pollutants, comprising: Based on the mole number of organic pollutants in a pollution source, a contact electrocatalyst is added to the pollution source in a mole ratio to carry out electrocatalytic degradation of the organic pollutants, wherein the contact electrocatalyst includes the contact electrocatalyst as described in any one of claims 1 to 3 or the contact electrocatalyst prepared by the method described in any one of claims 4 to 6.

8. The method as described in claim 7, wherein, The pollution sources include industrial wastewater, domestic wastewater, agricultural wastewater, and soil and groundwater; the organic pollutants include monoazo dyes, diazo dyes, triazo dyes, or polyazo dyes.

9. The method as described in claim 7, wherein, The molar ratio of the contact electrocatalyst to the organic pollutant is 1:(0.1 to 10).

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