Abstract
Sustainable water-splitting hydrogen production has long been considered one of the most promising energy conversion technologies, but enormous challenges remain: For instance, water electrolysis suffers from high overpotential and over energy consumption under neutral pH conditions. Here, taking advantage of the memory effect of layered double hydroxide (LDH), we report an energy-efficient neutral water electrolyzer material based on LDH with multiple vacancy defects. Benefiting from the improved electrical conductivity, larger electrochemical surface area (ECSA), and faster charge transfer, the NiFe LDH with O, Ni, and Fe vacancies exhibits a low overpotential of 87 mV at 10 mA/cm2 for hydrogen evolution reaction (HER) in a pH 7 buffer electrolyte. Impressively, the as-fabricated vacancy-containing NiFe LDH (v-NiFe LDH) splits water with a current density of 10 mA/cm2 at a1.60 V in a two-electrode device, outperforming most other water-splitting catalysts in neutral media. Such an electrolyzer setup could be powered by a commercial 2.0 V solar cell, producing hydrogen at a current density as high as 100 mA/cm2.
Original language | English |
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Pages (from-to) | 1412-1418 |
Number of pages | 7 |
Journal | ACS Energy Letters |
Volume | 4 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2019 Jun 14 |
Bibliographical note
Funding Information:The authors thank Mr. Quan Gan at Caltech for helpful discussion. This study was supported by the Natural Science Foundation of China, the Program for Changjiang Scholars and Innovative Research Team in the University, and the long-term subsidy mechanism from the Ministry of Finance and the Ministry of Education of P. R. China. S.-M. Bak, E. Hu, and X.-Q. Yang at Brookhaven National Laboratory (BNL) were supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Vehicle Technology Office of the U.S. Department of Energy through the Advanced Battery Materials Research (BMR) Program, including Battery500 Consortium under contract DE-SC0012704. This research used beamlines 8-ID (ISS) and 28-ID-2 (XPD) of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DESC0012704. Z. Cai thanks the China Postdoctoral Science Foundation (No. 2018M640694). We also thank 1W1B beamline station of Beijing Synchrotron Radiation Facility.
Publisher Copyright:
© 2019 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Chemistry (miscellaneous)
- Renewable Energy, Sustainability and the Environment
- Fuel Technology
- Energy Engineering and Power Technology
- Materials Chemistry