CNT/ZIF-67@ZIF-8/Ru-Cu催化剂的制备及催化性能研究

PREPARATION AND CATALYTIC PERFORMANCE OF CNT/ZIF-67@ZIF-8/RU-CU CATALYSTS

室温下制备了负载Ru和Cu两种不同的金属CNT/ZIF-67@ZIF-8/Ru-Cu催化剂,并用于催化氨硼烷水解产生氢气。实验结果表明,催化剂量越大,底物量越少,催化效率越高,15 mg催化剂催化45 mg氨硼烷发生水解时反应速率最大,产氢体积从20 mL增加到40 mL时的反应速率为1.824 L/min·g cat,转化频率(TOF值)为0.0814 mol/min·g cat,但其在反应结束时产氢量最少约73 mL。氨硼烷的量为60 mg和75 mg时反应速率和TOF值稍低但最终产氢量约120 mL。CNT/ZIF-67@ZIF-8/Ru-Cu催化剂催化氨硼烷水解反应的活化能较高,为127.5 kJ/mol,重复使用3次仍有较好的催化活性,但仍需进一步提高稳定性以改善循环使用次数和降低活化能。

CNT/ZIF-67@ZIF-8/Ru-Cu catalyst was prepared,which was used as catalysts for the catalytic decomposition of ammonia borane to produce hydrogen.The experimental results reveals that the catalytic efficiency depended on the larger the catalyst amount and the less substrate amount.When the hydrogen production volume increases from 20 mL to 40 mL,the reaction rate is 1.824 L/min·g cat,and the TOF value is 0.0814 mol/min·g cat at 15 mg of catalyst and 45 mg of aminoborane.The reaction rate and TOF value are slightly lower by increasing the amount of aminoborane to 60 mg and 75 mg,but the final hydrogen production is higher than that of 45 mg of aminoborane.The activation energy for the hydrolysis of ammonia borane is 127.5 KJ/mol.The CNT/ZIF-67@ZIF-8/Ru Cu catalyst exhibits good catalytic activity after being used three times.However,the stability of CNT/ZIF-67@ZIF-8/RuCu catalyst is needed to improve for increasing the cycle life and reducing the Ea of hydrolysis reaction.