University Chemistry ›› 2025, Vol. 40 ›› Issue (4): 399-407.doi: 10.12461/PKU.DXHX202407102

Special Issue:

• Between Teacher and Student • Previous Articles     Next Articles

Teaching Classical Contents Newly: Taking Temperature–Entropy Diagram as an Example

Qiang Wu, Wenhua Hou   

  1. School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
  • Received:2024-07-24 Accepted:2024-08-15 Published:2025-04-25
  • Contact: Wenhua Hou E-mail:whou@nju.edu.cn

Abstract: In the reversible thermodynamic cycles, the relationship between temperature and entropy of the system can be expressed by the temperature–entropy diagram (T–S diagram), which can simultaneously visualize the heat absorbed from the surroundings and the work done by the system, and thus the ideal heat-to-work conversion efficiency can be theoretically calculated accordingly. This article summarizes the application of T–S diagram in the several classical thermodynamic cycles for heat-to-work conversion, and also introduces the recent advances in the new energy-harvesting processes from the low-grade heat sources based on the temperature and/or concentration effects of electrode potential under the direction of T–S diagram. The purpose of this article is to deepen people’s understanding and also to broaden the application range of T–S diagram.

Key words: Temperature-entropy diagram, Heat-to-work conversion efficiency, Thermodynamic cycles, New energy utilization