【摘要】 铜钯双金属纳米颗粒是一种新型纳米催化剂。该纳米颗粒的烧结过程显著影响其比表面积和表面成分，这对催化效率起着关键作用。为了深入理解铜钯双金属纳米颗粒的烧结机制，本研究基于分子动力学探究了直径为6 nm的铜钯异种金属纳米颗粒在不同温度下的等温烧结行为。结果表明，烧结颈的长大速度同温度相关。在温度为（0.5～0.8）T_m时，两者呈线性相关，R_sn=T/T_m+1.1;在温度为（0.8～1.0）T_m时，烧结颈随温度的增加迅速长大，两者关系近似为R_sn=35（T/T_m）²-52.5 T/T_m)+21.5。铜钯纳米颗粒初期的烧结行为主要由低熔点表面铜原子扩散所驱动。同时，较低的混合焓促进铜、钯原子结合的作用，提高钯原子的扩散能力，驱动着铜钯纳米颗粒烧结由表向里的持续进行。更多还原

【Abstract】 Bimetallic copper-palladium（Cu-Pd） nanoparticles are a novel type of nanocatalyst. The sintering process of these nanoparticles plays a crucial role in catalytic efficiency through changes in specific surface area and surface composition. To gain a deeper understanding of the sintering mechanism of Cu-Pd bimetallic nanoparticles, this study employed molecular dynamics simulations to investigate the isothermal sintering behavior of 6 nm diameter Cu-Pd heterostructured nanoparticles at various temperatures. The results indicate a correlation between the growth rate of sintering necks and temperature. within the range of（0.5～0.8） T_m（melting temperature）, the relationship is linear, R_sn=T/T_m+1.1; while within the range of（>0.8～1.0） T_m, the growth of sintering necks rapidly accelerates with increasing temperature, showing an approximate exponential relationship, R_sn=35（T/T_m）²-52.5（T/T_m）+21.5. The initial sintering behavior of Cu-Pd nanoparticles is primarily driven by the diffusion of low-melting-point copper surface atoms. Additionally, the relatively low mixing enthalpy facilitates the bonding between Cu and Pd atoms, enhancing the diffusion capability of Pd atoms, driving the continuous inward sintering of Cu-Pd nanoparticles.更多还原