Regulation of the d- band center of metal-organic frameworks for energy- saving hydrogen generation coupled with selective glycerol oxidation

• 成果类型: Article
• 署名作者: He, Yuqian; Ma, Zheng; Yan, Feng; Zhu, Chunling; Shen, Tongyang; Chou, Shulei; Zhang, Xiao; Chen, Yujin
• 署名单位: Harbin Engineering University; Harbin Engineering University; Wenzhou University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9803
• DOI: 10.1073/pnas.2320777121
• 发表日期: 2024-04-23

摘要

The hybrid electrolyzer coupled glycerol oxidation (GOR) with hydrogen evolution reaction (HER) is fascinating to simultaneously generate H 2 and high value - added chemicals with low energy input, yet facing a challenge. Herein, Cu - based metal-organic frameworks (Cu - MOFs) are reported as model catalysts for both HER and GOR through doping of atomically dispersed precious and nonprecious metals. Remarkably, the HER activity of Ru - doped Cu - MOF outperformed a Pt/C catalyst, with its Faradaic efficiency for formate formation at 90% at a low potential of 1.40 V. Furthermore, the hybrid electrolyzer only needed 1.36 V to achieve 10 mA cm -2 , 340 mV lower than that for splitting pure water. Theoretical calculations demonstrated that electronic interactions between the host and guest (doped) metals shifted downward the d - band centers ( epsilon d ) of MOFs. This consequently lowered water adsorption and dissociation energy barriers and optimized hydrogen adsorption energy, leading to significantly enhanced HER activities. Meanwhile, the downshift of epsilon d centers reduced energy barriers for rate - limiting step and the formation energy of OH*, synergistically enhancing the activity of MOFs for GOR. These findings offered an effective means for simultaneous productions of hydrogen fuel and high value - added chemicals using one hybrid electrolyzer with low energy input.