负载型Ni-Co-P/CNFs催化剂的制备及释氢性能

Hydrogen generation from the hydrolysis of sodium borohydride solution over the supported Ni-Co-P/CNFs catalysts

以纳米碳纤维(CNFs)为基体材料,采用化学镀法在CNFs表面沉积了Ni-Co-P催化剂。研究了催化剂用量,硼氢化钠、氢氧化钠浓度,温度等对碱性硼氢化钠溶液水解释氢的影响。电感耦合等离子体原子发射光谱法(ICP-AES)测试得出负载型Ni-Co-P催化剂含镍13.30%(质量分数,下同)、钴82.25%、磷4.45%。硼氢化钠水解释氢实验结果表明,产氢速率与催化剂用量呈线性关系。当温度为45℃、催化剂浓度为7.5 g/L、氢氧化钠浓度为5%、硼氢化钠浓度为2.5%时,氢气释放速率达到最大值18.044 L/(g·min)。通过对负载型催化剂Ni-Co-P/CNFs催化碱性硼氢化钠溶液释放氢气动力学研究表明,该催化剂的活化能Ea为51.57 k J/mol。

The Ni-Co-P catalysts supported on carbon nanofibers（CNFs） were prepared via electroless deposition;the mass fractions of nickel,cobalt and phosphorus in Ni-Co-P layer are 13.30%,82.25%and4.45%,respectively,as determined by ICP-AES.The effects of catalyst amount,sodium borohydride and sodium hydroxide concentrations and reaction temperature on the rate of hydrogen generation in the hydrolysis of alkaline NaBH4 solution were investigated.The results indicated that the rate of hydrogen generation is proportional to the used catalyst amount;a maximum hydrogen generation rate of 18.044 L/（g·min） is achieved at 45 ℃ by hydrolysis of 2.5%NaBH4 solution containing 5%NaOH and 7.5 g/L Ni-Co-P/CNFs catalyst with a Ni-Co-P loading of 18.127%.Moreover,a kinetic study shows that the activation energy for the hydrolysis of alkaline NaBH4 solution under those conditions is 51.57 kJ/mol.