摘要
CoS_(2)因具有高电导、高热分解温度等特性,而被作为热电池正极材料而进行广泛研究。在热电池工作过程中,CoS_(2)会持续发生热分解反应,导致热电池容量下降甚至危及使用安全。但是,目前关于CoS_(2)热分解特性的研究是相对缺乏的,导致其对CoS_(2)基热电池的支撑设计存在明显不足。因此,将通过采用高温原位X射线衍射法、同步热分析法等,对CoS_(2)的热分解机理及反应动力学特性进行研究,并构建出相应的反应动力学模型。结果表明,在30~750℃温度区间内,CoS_(2)的热分解过程可分为CoS_(2)→1/3 Co_(3)S_(4)+1/3 S_(2),1/3 Co_(3)S_(4)→CoS+1/6 S_(2)两个步骤,其反应机理为柱状对称的相边界反应,所对应的机理函数积分形式为G(α)=1-(1-α)1/2。
CoS_(2)has been widely studied as cathode materials of thermal batteries because of its excellent electronic conductivity and thermal stability.During the working process,CoS_(2)would undergo continuously pyrolysis reaction,leading to the loss of discharge capacity and causing possible safety issues.This investigation focused the pyrolysis reaction mechanism and kinetics of CoS_(2),by using the high-temperature in-situ X-ray diffraction,thermal analysis and other technologies,aiming to support the design of thermal batteries.The results confirm that,within the temperature range of 30-750℃,the thermal decomposition process of CoS_(2)can be divided into CoS_(2)→1/3 Co_(3)S_(4)+1/3 S_(2)and 1/3 Co_(3)S_(4)→CoS+1/6 S_(2).It follows the symmetric cylindrical phase boundary reaction,with the mechanism function is G(α)=1-(1-α)^(1/2).
作者
韦义成
曹勇
马士平
崔艳华
WEI Yicheng;CAO Yong;MA Shiping;CUI Yanhua(Institute of Electronic Engineering,China Academy of Engineering Physics,Mianyang Sichuan 621900,China)
出处
《电源技术》
CAS
北大核心
2023年第12期1631-1636,共6页
Chinese Journal of Power Sources
基金
国家自然科学基金(U1930208)。
关键词
热电池
CoS_(2)
热分解
机理
动力学
thermal batteries
CoS_(2)
thermal decomposition
mechanism
kinetics
