过渡金属磷化物催化氨硼烷和硼氢化钠水解制氢研究

发布时间：2018-06-09 17:28

  本文选题：硼氢化钠 + 氨硼烷　； 参考：《云南师范大学》2017年硕士论文

【摘要】：氢气因具有储量丰富、能量密度高、环境友好等优势,被认为是一种可再生的绿色新能源。要使氢气得到广泛的运用,首先需要解决的问题是如何高效、安全地储存和运输氢气。化学储氢材料(NaBH_4,NH_3BH_3,N_2H_4,HCOOH等)具有储氢密度高、体积小等优势能够有效地解决上述问题。要使化学储氢材料快速高效的释放氢,最有效的方法就是找到一种廉价高效的催化剂。过渡金属磷化物作为催化化学储氢材料水解产氢的催化剂被研究者广泛研究。本论文以开发高效、廉价的过渡金属磷化物为立足点,制备了多种过渡金属磷化物,并用来催化氨硼烷和硼氢化钠水解,同时找到了最佳的水解制氢条件。具体研究结果如下:1、以次磷酸钠为磷源,硝酸钴、氯化钴等廉价金属盐为金属源,制备了一系列的过渡金属磷化物(CoP、Co_2P、Ni_2P、Cu_3P和FeP)纳米粒子,并用XRD、SEM、TEM等进行了表征。2、以Co_2P为催化剂催化氨硼烷水解释氢,并对反应条件进行优化。研究表明,催化剂的用量、氨硼烷的浓度、碱浓度及温度对Co_2P催化氨硼烷水解释氢都有较大的影响。3、研究了相同条件下,用多种过渡金属磷化物催化NaBH_4水解制备氢气。经过比较我们发现,室温下,CoP的催化效果最佳,Co_2P次之,FeP的效果最差。4、与其他已报道的Co-P催化NaBH4水解制氢相比,CoP纳米粒子的催化活性和可循环性较好。25℃时和35℃时,CoP催化NaBH_4水解的TOF值依次为3097.62 mL·min~(-1)·g~(-1),4704.14 m L·min~(-1)·g~(-1)。5、用Co_2P纳米粒子作为催化剂,来催化NaBH4水解制氢,通过对反应条件的优化,得到在30℃时,Co_2P催化NaBH_4水解的TOF值为2307.2mL·min~(-1)·g~(-1),在35℃时,其TOF值为3323.4 m L·min~(-1)·g~(-1)。
[Abstract]:Hydrogen is considered to be a renewable green energy source because of its rich reserves, high energy density and environmental friendliness. How to store and transport hydrogen efficiently and safely is the first problem to be solved in order to make hydrogen widely used. The chemical hydrogen storage material NaBH _ S _ 4 / NH _ 3BH _ S _ 3T _ 3N _ 2H _ 2H _ 2H _ 2H _ OH) has the advantages of high hydrogen storage density and small volume, which can effectively solve the above problems. The most effective way to release hydrogen quickly and efficiently from chemical hydrogen storage materials is to find a cheap and efficient catalyst. Transition metal phosphates as catalysts for the hydrolysis of hydrogen storage materials have been widely studied. In this paper, a variety of transition metal phosphates were prepared based on the development of efficient and cheap transition metal phosphates, which were used to catalyze the hydrolysis of aminoborane and sodium borohydride. At the same time, the optimum conditions for the production of hydrogen were found. The specific results are as follows: using sodium hypophosphite as phosphorus source, cobalt nitrate, cobalt chloride and other cheap metal salts as metal sources, a series of transition metal phosphates have been prepared. It was characterized by XRDX SEM TEM et al. Cos _ 2P was used as catalyst to catalyze the interpretation of hydrogen from ammonium-borane water and the reaction conditions were optimized. The results show that the amount of catalyst, the concentration of aminoborane, the concentration of base and temperature have great influence on the hydrogen interpretation of ammonia borane water catalyzed by Co2P. Under the same conditions, the catalytic hydrolysis of NaBH4 with a variety of transition metal phosphates has been studied. After comparison, we found that The catalytic activity of cop was the best at room temperature, followed by FeP. 4. Compared with other reported Co-P catalytic hydrolysis of NaBH4 to produce hydrogen, the catalytic activity and circulability of cop nanoparticles were better than those of other reported Co-P catalysts. 25 鈩，

本文编号：2000542