等离子体催化铁系金属催化剂氨分解制氢研究进展

RESEARCH PROGRESS IN AMMONIA DECOMPOSITION OF IRON SERIES METAL CATALYSTS ASSISTED BY PLASMA

氢能作为一种零碳二次能源被广泛应用于各种工业领域.氨作为一种储氢载体,具有储氢量高(17.6 wt%)、能量密度高和易液化等特点,其分解产物只有氢气和氮气,符合国家“碳达峰,碳中和”的战略发展方向.但是氨分解的活化能高,反应条件较为苛刻.因此,开发安全、高效、低成本的氨分解制氢技术对于氢能发展具有重要意义.文章首先阐明了氨分解反应的基本原理,介绍了铁系金属催化剂催化NH3分解制氢的研究进展,Fe,Co和Ni基催化剂的NH3分解活性较高,因为其金属−氮的结合能适中,之后从调控活性金属中心出发,通过加入第二金属、调控形貌、缺陷/掺杂、构建金属−载体相互作用等方面设计提高氨分解的活性,并采用多种表征方法揭示催化剂的构效关系.除铁系催化剂外,还重点介绍了提高氨分解效率的等离子体技术,回顾了等离子体的原理、种类、作用机制以及在辅助催化氨制氢方面的协同效应.文章综述了催化NH3分解的反应机理,介绍了目前氨分解制氢催化剂设计的最新进展,总结了提高NH3分解制氢的策略,强调了等离子体在辅助催化NH3分解的优势.对于今后氨分解制氢催化剂的开发和应用具有一定的参考价值,期望为未来氨制氢的技术发展和工业化应用提供新思路.

Hydrogen energy is widely used in various industrial fields as a zero-carbon secondary energy source.As a hydrogen storage carrier,ammonia has the advantages of high hydrogen storage capacity(17.6 wt%),high energy density and easy liquefaction,and its decomposition products are only hydrogen and nitrogen,which is in line with the national strategic development direction of“carbon peak,carbon neutrality”.However,the activation energy of ammonia decomposition is high and the reaction conditions are harsh.Therefore,the development of safe,efficient and cheap ammonia decomposition hydrogen production technology is crucial for the development of hydrogen energy.In this paper,the basic principle of ammonia decomposition reaction is explained,and the research work of NH3 decomposition to hydrogen production catalyzed by various metal catalysts is introduced.Fe,Co and Ni based catalysts show higher NH3 decomposition activity because of their moderate metal-nitrogen binding energy.Beginning from the regulation of active metal centers,the researchers designed to improve the activity of ammonia decomposition by adding secondary metals,regulating morphology,defects/doping,constructing metal-carrier interactions,etc.The many characterization methods were used to reveal the structure-activity relationship of catalysts.In addition to the iron series catalysts,this paper also focuses on the plasma technology to improve the efficiency of ammonia decomposition and reveals the principle,types,mechanism of plasma and the synergistic effect in auxiliary catalytic ammonia hydrogen production.In this paper,the latest work in the design of ammonia decomposition catalyst for hydrogen production is introduced and the strategies for improving NH3 decomposition for hydrogen generation are summarized.The advantages of plasma-assisted NH3 decomposition are emphasized.This paper has certain reference value for the development and application of ammonia decomposition hydrogen generation catalysts,in order to provide a new idea for the development of ammonia hydrogen production technology and industrial application in the future.