First Principles‐Based Kinetics Analysis of CaO/Ca(OH)2 Thermochemical Energy Storage System Enhanced by Bimetallic Doping

Abstract

The Ca(OH) 2 /CaO thermochemical energy storage systems can meet the long‐term and long‐distance heat storage and transportation requirements of various industrial applications, including waste heat recovery and solar energy utilization. This study investigates how Li/La or Li/Ti dual‐doped crystal structures influence the dehydration process of Ca(OH) 2 by comparing their transition state, energy barrier, and electronic density of states. Its findings show that incorporating bimetal elements significantly reduces the energy barrier value: from 0.59 eV for undoped crystal to 0.09 eV for Li/La and 0.20 eV for Li/Ti dopant, respectively. Furthermore, this study assesses the impact of bimetal doping on the structural characteristics, morphology, and thermal storage properties using techniques such as X‐ray diffraction, scanning electron microscopy, and thermogravimetric analysis. Experimental results demonstrate that samples with small co‐doped Li and La elements (only the molar percentage is 5%) have an onset temperature decrease of ≈40 °C. This study expands the application range of the Ca(OH) 2 /CaO system while improving cycling stability.