用于在N-乙基咔唑储氢中制备超细负载型Ru纳米催化剂的镍铁层状双氢氧化物超声激发氢自由基

Ultrasound-excited hydrogen radical from NiFe layered double hydroxide for preparation of ultrafine supported Ru nanocatalysts in hydrogen storage of N-ethylcarbazole.

作者信息

Liu Xiaoran, Shi Jiaming, Bai Xuefeng, Wu Wei

机构信息

School of Chemistry and Material Science, Heilongjiang University, Harbin 150080, China.

School of Chemistry and Material Science, Heilongjiang University, Harbin 150080, China; Institute of Petrochemistry, Heilongjiang Academy of Sciences, Harbin 150040, China.

出版信息

Ultrason Sonochem. 2021 Dec;81:105840. doi: 10.1016/j.ultsonch.2021.105840. Epub 2021 Nov 20.

DOI:10.1016/j.ultsonch.2021.105840

PMID:34837735

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8637643/

Abstract

Highly active Ru nanoparticles (Ru NPs) supported on NiFe layered double hydroxide (Ru/NiFe-LDH) are prepared easily using ultrasound-assisted reduction method without chemical reductants and stabilizers. The plentiful hydroxyls on NiFe-LDH are excited into hydrogen radicals (H) under the action of ultrasound for reducing Ru to Ru. Ru NPs with an average particle size of 1.26 nm highly disperse on the mesopore-like surface of NiFe-LDH, which improve the catalytic performance for N-ethylcarbazole (NEC) hydrogenation. The experimental results show that 5Ru/NiFe-LDH-300-60 exhibits the best catalytic performance with 100% conversion of NEC, 98.88% yield of dodecahydro-N-ethylcarbazole (12H-NEC) and 5.77 wt% mass hydrogen storage capacity under the reaction conditions of 110 ℃, 6 MPa and m:m = 0.15 wt% for 80 min. The kinetics study shows that the apparent activation energy is only 25.15 kJ/mol, which is the lowest in the reported literatures. Ru complexes with O-contained groups on NiFe-LDH, improving the catalytic stability in NEC hydrogenation.

摘要

采用超声辅助还原法，无需化学还原剂和稳定剂，即可轻松制备负载在镍铁层状双氢氧化物（Ru/NiFe-LDH）上的高活性钌纳米颗粒（Ru NPs）。在超声作用下，NiFe-LDH上大量的羟基被激发成氢自由基（H），从而将Ru还原为Ru NPs。平均粒径为1.26 nm的Ru NPs高度分散在NiFe-LDH的类中孔表面，提高了对N-乙基咔唑（NEC）加氢的催化性能。实验结果表明，在110℃、6MPa、m:m = 0.15 wt%的反应条件下反应80min，5Ru/NiFe-LDH-300-60表现出最佳的催化性能，NEC转化率为100%，十二氢-N-乙基咔唑（12H-NEC）收率为98.88%，储氢容量为5.77 wt%。动力学研究表明，其表观活化能仅为25.15 kJ/mol，是已报道文献中最低的。Ru与NiFe-LDH上含O基团形成配合物，提高了NEC加氢反应中的催化稳定性。