Nickel Oxide-Based Iron-Iridium Co-Electrodeposited Catalyst, Preparation Method Thereof, and Application Thereof

Abstract

The present invention discloses a nickel oxide-based iron-iridium bi-electrocatalytic catalyst, its preparation method and application, belonging to the technical field of catalytic materials. In the present invention, a nickel oxide material is prepared as a nickel oxide working electrode, and a mixed solution of an iron precursor, an iridium precursor, and an OH - source is used as an electrolyte. Iron-iridium bimetal is deposited on the nickel oxide working electrode by electrochemical deposition to obtain a nickel oxide-based iron-iridium bi-electrocatalytic catalyst. The preparation method provided by the present invention realizes the multi-scale dispersion of two metal elements, iron and iridium, on the surface of the nickel oxide support. This multi-scale structure not only provides abundant catalytic active sites, enabling the catalyst to more efficiently adsorb and activate reactants during the reaction process, but also significantly enhances the electron transfer efficiency, thereby improving the catalytic activity of the catalyst. In addition, the synergistic effect of iron and iridium optimizes the electronic structure of the catalyst, further improving its catalytic performance.

1 . A method for preparing a nickel oxide-based iron-iridium double electrodeposited catalyst, characterized in that it comprises the following steps: 
 forming a Ni-alanine complex with DL-α-alanine as a ligand and a Ni 2+  source, and pyrolyzing at 550 ℃~620 ℃ in an air atmosphere to decompose the complex in the Ni-alanine complex, to obtain a nickel oxide material;   preparing the nickel oxide material into a nickel oxide working electrode, wherein a mixed solution of an iron precursor, an iridium precursor, and an OH -  source as an electrolyte are used, and iron-iridium bimetal is deposited on the nickel oxide working electrode by electrochemical deposition to obtain the nickel oxide-based iron-iridium double electrodeposited catalyst;   wherein, in the electrolyte, the molar ratio of the iridium precursor to the iron precursor is 1:0.2~2;   wherein, before the electrochemical deposition, the nickel oxide working electrode is electrochemically activated by using a standard three-electrode system, applying 0.5s~1.5s, -2V~-1.5V cathodic potential short pulses and 0.5s~1.5s, 1.5V~2V anodic potential short pulses sequentially to the nickel oxide working electrode in a solution containing OH - ;   wherein the electrochemical deposition is conducted via a chronoamperometry method, at a voltage of 5V~7V, and a time of the electrochemical deposition of 8000s~12000s.   
     
     
         2 . The method for preparing a nickel oxide-based iron-iridium double electrodeposited catalyst according to  claim 1 , wherein the molar ratio of the iridium precursor to the iron precursor in the electrolyte is 1:1. 
     
     
         3 . The method for preparing a nickel oxide-based iron-iridium double electrodeposited catalyst according to  claim 1 , wherein a cycle is one cathodic potential short pulse and one anodic potential short pulse, and the cycle is repeated 40 times to 60 times. 
     
     
         4 . The method for preparing a nickel oxide-based iron-iridium double electrodeposited catalyst according to  claim 1 , wherein the preparation method of the nickel oxide working electrode is: ultrasonically mixing the nickel oxide material, ethanol, and Nafion, and drop-coating on carbon paper to obtain the nickel oxide working electrode with a nickel oxide material loading of 0.8mg/cm 2 ~2.3mg/cm 2 . 
     
     
         5 . The method for preparing a nickel oxide-based iron-iridium double electrodeposited catalyst according to  claim 1 , wherein the molar ratio of the Ni 2+  source to the DL-α-alanine is 1:4~5. 
     
     
         6 . The method for preparing a nickel oxide-based iron-iridium double electrodeposited catalyst according to  claim 1 , wherein the pyrolysis time is 1.5h~3h. 
     
     
         7 . A nickel oxide-based iron-iridium double electrodeposited catalyst, prepared by the preparation method according to  claim 1 . 
     
     
         8 . An application of the nickel oxide-based iron-iridium double electrodeposited catalyst according to  claim 7  in catalyzing water electrolysis.