4results about How to "Reduce hydrogen evolution overpotential" patented technology

The application discloses an MOF-derived nitrogen cobalt hetero-nano box electrocatalyst, a preparation method and application, and the method steps for preparing the catalyst are as follows: S1: preparation of a ZIF-67 template; S2: dissolving the ZIF-67 template in S1 in anhydrous methanol, ultrasonic stirring and dissolving, and recording as solution A; S3: dissolving 1H-1,2,3-triazole in an anhydrous methanol solution and recording as solution B; S4: adding the solution B in S3 into the solution A in S2, stirring, and then standing to perform a substitution reaction; and S5: centrifuging, drying and carbonizing the product after the reaction in S4 under nitrogen protection to obtain the MOF-derived nitrogen cobalt hetero-nano box electrocatalyst. The 2-methyl imidazole in the imidazole zeolite framework ZIF-67 is partially substituted by a high-energy nitrogen-containing ligand 1H-1,2,3-triazole ligand, a rich nitrogen source is provided, and the coordination environment of cobalt atoms is locally constrained, so that the prepared electrocatalyst has a lower hydrogen evolution overpotential under the alkaline condition of 1 mol / L KOH aqueous solution.

The application relates to the technical field of water electrolysis cathode preparation, in particular to an alkaline water electrolysis hydrogen production cathode and a preparation method and application thereof. The preparation method comprises the following steps: mixing nickel powder, aluminum powder, platinum group metal powder and graphene powder to obtain mixed metal powder; adopting plasma spraying to spray the mixed metal powder to the surface of an electrode base material to form a coating, thereby obtaining a hydrogen evolution electrode; adopting alkaline solution to activate the hydrogen evolution electrode to form a catalytic layer on the surface of the electrode base material, thereby obtaining an alkaline water electrolysis hydrogen production cathode. The platinum group metal and the graphene are collectively melted with the nickel and the aluminum at high temperature, and then are sprayed to the surface of the electrode base material by the plasma spraying mode to form the coating, so that the coating and the base body have better combination, the coating is more uniform, the service life of the electrode is improved, and the hydrogen evolution potential is lower.

The application relates to the field of electrocatalysis, and particularly relates to a high-catalytic-activity Ni-Se-HREE hydrogen evolution electrode and a preparation method thereof.The atomic content percentage of the surface of the nickel-based hydrogen evolution electrode coating layer is as follows: Se: 6-10%; Gd: 0.1-1.0%, and the rest is Ni; or the atomic content percentage of the surface of the nickel-based hydrogen evolution electrode coating layer is as follows: Se: 5-20%; Lu: 1-5%, and the rest is Ni.After optimization, the hydrogen evolution overpotential of the prepared Ni-Se-HREE hydrogen evolution electrode material is less than or equal to 43 mV; after long-time electrolysis of the electrode for 1200 h, the stability is good, the requirements of low hydrogen evolution overpotential, high catalytic activity and high stability are met, and the electrode can be widely applied to the water electrolysis hydrogen production industry.

The present application relates to the field of soil purification and hydrogen energy technology, and specifically relates to a preparation method of biomass-derived carbon material for absorbing heavy metal ions from soil, comprising the following steps: S1, transplanting plants in soil contaminated by heavy metals, and obtaining plants containing heavy metal ions after normal planting and cultivation for two months; S2, cleaning and freeze-drying the plants containing heavy metal ions to obtain dried plants retaining original tissue structure; S3, calcining the freeze-dried plants retaining original tissue structure, and obtaining carbonized biomass-derived carbon material after cooling. The present application innovates the method for obtaining biomass-derived carbon material, and the preparation process is simple. When the biomass-derived carbon material is used as a catalyst for alkaline water electrolysis hydrogen production, it shows a low hydrogen evolution overpotential. Meanwhile, the biomass-derived carbon material proposed can purify soil and realize high-value utilization of biomass resources in the field of new energy, showing good innovation.