热容
纳米晶
工作(物理)
材料科学
体积热容
拉曼光谱
化学物理
比热
热力学
声子
化学
纳米技术
凝聚态物理
传热
热撒布器
物理
光学
作者
Kai Gu,Haizhen Wu,Jing Su,Ping Sun,Ping‐Heng Tan,Haizheng Zhong
出处
期刊:Nano Letters
[American Chemical Society]
日期:2024-03-21
卷期号:24 (13): 4038-4043
标识
DOI:10.1021/acs.nanolett.4c01021
摘要
Specific heat capacity is one of the most fundamental thermodynamic properties of materials. In this work, we measured the specific heat capacity of PbSe nanocrystals with diameters ranging from 5 to 23 nm, and its value increases significantly from 0.2 to 0.6 J g–1 °C–1. We propose a mass assignment model to describe the specific heat capacity of nanocrystals, which divides it into four parts: electron, inner, surface, and ligand. By eliminating the contribution of ligand and electron specific heat capacity, the specific heat capacity of the inorganic core is linearly proportional to its surface-to-volume ratio, showing the size dependence. Based on this linear relationship, surface specific heat capacity accounts for 40–60% of the specific heat capacity of nanocrystals with size decreasing. It can be attributed to the uncoordinated surface atoms, which is evidenced by the appearance of extra surface phonons in Raman spectra and ab initio molecular dynamics (AIMD) simulations.
科研通智能强力驱动
Strongly Powered by AbleSci AI