无机材料学报 ›› 2022, Vol. 37 ›› Issue (2): 223-229.DOI: 10.15541/jim20210164

所属专题: 【虚拟专辑】计算材料 【能源环境】CO2绿色转换

• 研究快报 • 上一篇    下一篇

太阳能驱动的两步热化学循环二氧化碳裂解反应活性材料的热力学与第一性原理评价

冯清影, 刘东, 张莹, 冯浩, 李强   

  1. 南京理工大学 能源与动力工程学院, 南京 210094
  • 收稿日期:2021-03-15 修回日期:2021-05-20 出版日期:2022-02-20 网络出版日期:2021-06-10
  • 作者简介:冯清影(1996-), 女, 博士研究生. E-mail: fqy@njust.edu.cn

Thermodynamic and First-principles Assessments of Materials for Solar-driven CO2 Splitting Using Two-step Thermochemical Cycles

FENG Qingying, LIU Dong, ZHANG Ying, FENG Hao, LI Qiang   

  1. School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
  • Received:2021-03-15 Revised:2021-05-20 Published:2022-02-20 Online:2021-06-10
  • Contact: ZHANG Ying, PhD. E-mail: ying.zhang@njust.edu.cn; LI Qiang, professor. E-mail: liqiang@njust.edu.cn
  • About author:FENG Qingying(1996-), female, PhD candidate. E-mail: fqy@njust.edu.cn
  • Supported by:
    Basic Science Center Program for Ordered Energy Conversion of the National Natural Science Foundation of China (51888103); National Natural Science Foundation of China (52006103); Fundamental Research Funds of the Central Universities (30919011403, 30920021137)

摘要: 太阳能驱动两步热化学循环裂解二氧化碳可制备碳中性燃料, 为替代化石燃料、缓解全球变暖提供了技术途径。新型活性材料的开发对该技术非常重要。已有研究通常采用能量描述符(材料生成焓或氧空位生成能)评价候选材料, 忽略了材料熵的重要性。本研究采用活性材料的熵和生成焓的组合作为描述符, 提出评价准则, 开展材料可行性的热力学分析。结果表明, 活性材料应兼具较大的正的熵变与较小的生成焓变。在此基础上, 本研究以氧化铈和钐掺杂的氧化铈为例, 发展了基于第一性原理的活性材料熵和生成焓的计算方法, 为新型材料的筛选与开发提供基础。计算结果揭示了极化子振动熵以及氧空位和极化子构型熵对活性材料熵变的贡献。

关键词: 二氧化碳裂解, 两步热化学循环, 第一性原理, 熵, 太阳能制燃料

Abstract: Carbon-neutral fuel production by solar-driven two-step thermochemical carbon dioxide splitting provides an alternative to fossil fuels as well as mitigates global warming. The success of this technology relies on the advancements of redox materials. Despite the recognition of the entropic effect, usually energy descriptors (enthalpy of formation or energy of oxygen-vacancy formation) were used for computational assessment of material candidates. Here, in the first step, the criteria was derived based on the combination of solid-state change of entropy and formation enthalpy, and was used to thermodynamically assess the viability of material candidates. In the thermodynamic map, a triangular region, featuring large positive solid-state changes of entropy and small enough solid-state changes of formation enthalpy, was found for qualified candidates. Next, a first-principles DFT+U method was presented to fast and reasonably predict the solid-state changes of entropy and formation enthalpy of candidate redox materials, exemplified for pure and Samaria-doped ceria, so that new redox materials can be added to the thermodynamic map. All above results highlight the entropic contributions from polaron-defect vibrational entropy as well as ionic (oxygen vacancies) and electronic (polarons) configurational entropy.

Key words: carbon dioxide splitting, two-step thermochemical cycle, first principles, entropy, solar fuel

中图分类号: