关键词: 熵-焓调控, 热力学平衡, 反应动力学, 过渡态理论, 构型熵

Abstract: Entropy, enthalpy and Gibbs free energy are core concepts in thermodynamics and statistical physics, with fundamental theoretical and applied value for understanding chemical reactions kinetics and energy conversion．However, in undergraduate teaching these concepts are often presented in isolation, lacking systematic links to microscopic mechanisms, which hinders students from understanding macroscopic energy changes at the molecular scale．This paper proposes a teaching framework centered on the main line of “macroscopic concepts-microscopic pictures-quantitative measurements” integrating thermodynamics, reaction kinetics, and transition state theory into a unified knowledge system. Using CO2 methanation as an example, we combine experimental design with thermodynamic parameter measurements to reveal the mechanism of enthalpy-entropy synergy in enhancing catalytic efficiency. In particular, we highlight how local field-induced increases in activation entropy (ΔS) and decrease in reaction enthalpy (ΔH) via possible routes can lower the activation barrier (ΔG) through modulation of intermediate surface configurations and electronic relaxation, thereby accelerating the reaction. This teaching design helps students establish the “structure-energy-rate” relationship underlying molecular motion and intermediate evolution. Teaching practice demonstrates that this approach deepens the understanding of the essence of thermodynamics and improves quantitative analysis skills, providing a teaching strategy in physics, chemistry and materials courses．

Key words: entropy-enthalpy synergy, thermodynamic equilibirum, reaction kinetics, transition state theory, configuration entropy