Study On The Preparation Of Cobalt-Based Catalyst And The Catalytic Properties For Hydrogen Generation From Hydrolysis Of Potassium Borohydride

Hydrogen energy,as one of the most competitive new energy sources for future energy development,has attracted high attention in recent years.Among the many hydrogen storage materials,borohydrides are considered a promising hydrogen storage material because of their characteristics of high weight ratio,high volume hydrogen density,high storage safety and high purity of hydrogen production.To accelerate the process of potassium borohydride reaction for hydrogen production,highly efficient catalysts are needed.However,both in the preparation process and in the catalytic reaction,the agglomeration and stacking of the catalyst will seriously affect its catalytic performance.The preparation of new cobalt-based catalyst improve the hydrogen production rate of potassium borohydrode,solve the problem of catalyst stacking and improve the overall circulation performance of the catalyst.In the case of ultrasonic vibration assistance,this paper loaded the Co-B nanoparticles onto MXene by chemical reduction reaction using sodium borohydride as a reductant to obtain CoB/MXene.The morphology,structure,and constituents of Co-B/MXene were analyzed by XRD,SEM,TEM,XPS and EDX.It was found that the material had the best performance when MXene was 25 wt%,and the catalytic potassium borohydride hydrogenation rate reached 4637 mL·min-1·g-1,reaction activation energy is 52.26 kJ·mol-1,at 30℃ and alkaline conditions.Using chemical reduction,this paper prepared a series of Co-Mo-B materials with different molar content ratios of Co and Mo.The morphology,structure and composition of the materials were studied by XRD,SEM,TEM,XPS and EDX.It was found that the Co-Mo-B material showed the best catalytic performance when Co:Mo=7:3,and the hydrogen production rate reached 5310 mL·min-1·g-1,reaction activation energy is 42.3 kJ·mol-1 under 30℃ and alkaline conditions.The Co-Mo-Ni-B/ZIF-67 catalyst was prepared by doping the Ni metal and loading the new Co-Mo-Ni-B material onto the ZIF-67.The interaction between the three metals was explored,and the influence of the active material load on the catalyst performance was also studied.The morphological structure and composition of the material were investigated by XRD,SEM,TEM,XPS and EDX.Through research,it is determined that Co-Mo-Ni-B/ZIF67 had the best performance when(Co+Mo):Ni=10:1 and the loading amount of active material is 7.5%.Under the alkaline condition and 30℃,the hydrogen production rate reached 17400 mL·min-1·g-1,and the activation energy of the reaction was 20.04 kJ·mol-1.