Deep insight of unique phase transition behaviors and mechanism in Zr_(2)Co-H isotope system with ultra-low equilibrium pressure

作     者：Yang Liu Pan-Pan Zhou Xue-Zhang Xiao Jia-Cheng Qi Jia-Peng Bi Tiao Ying Xing-Wen Feng Yan Shi Wen-Hua Luo Li-Xin Chen Yang Liu;Pan-Pan Zhou;Xue-Zhang Xiao;Jia-Cheng Qi;Jia-Peng Bi;Tiao Ying;Xing-Wen Feng;Yan Shi;Wen-Hua Luo;Li-Xin Chen

作者机构：State Key Laboratory of Silicon MaterialsSchool of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Institute of MaterialsChina Academy of Engineering PhysicsMianyang 621907China Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang ProvinceHangzhou 310013China 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2024年第43卷第1期

页      面：212-224页

核心收录：

学科分类：08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：financially supported by the National Key Research and Development Program of China (No.2022YFE03170002) the National Natural Science Foundation of China (Nos.52071286 and U2030208) 

主　　题：Zr_(2)Co alloy Tritium-getter materials Ultralow equilibrium hydrogen pressure Phase transition mechanism 

摘      要：Efficient capture,safe storage and release of tritium from the international thermonuclear experimental reactor(ITER) reaction exhaust gas is a perplexing problem,and the development of an efficient tritium-getter material with ultra-low hydrogenation equilibrium pressure is considered as a reliable *** this work,Zr_(2)Co alloy was selected as a tritium-getter material and prepared through induction levitation *** performance test results show that Zr_(2)Co exhibits an ultra-low hydrogenation equilibrium pressure of 3.22 × 10^(-6) Pa at 25℃ and excellent hydriding kinetics under a low hydrogen pressure of 0.005 ***,unique phase transition behaviors were presented in Zr_(2)Co-H ***,Zr_(2)CoH_(5) formed by Zr_(2)Co hydrogenated at room temperature is initially decomposed into ZrH_(2) and ZrCoH_(3) at200 ℃.With the temperature increasing to 350 ℃,ZrCoH_(3)is dehydrogenated to ZrCo,and then ZrCo further reacts with ZrH_(2) at 650 ℃ to reform Zr_(2)Co and *** the staged phase transition pathways during dehydrogenation,the decomposition of Zr_(2)CoH_(5) occurs preferentially,which is well accordance with both the smallest reaction energy barrier and the maximum reaction spontaneity that are determined respectively from kinetics activation energy and thermodynamics Gibbs free ***,first principles calculation results indicate that the stronger binding of hydrogen in interstitial environments of ZrCoH_(3)and ZrH_(2) triggers the hydrogen-stabilized phase transformation of Zr_(2)CoH_(5).The unique phase transition mechanisms in Zr_(2)Co-H system can shed light on the further exploration and regulation of analogous staged phase transition of hydrogen storage materials.