Fabrication of nanoporous Ni and NiO via a dealloying strategy for water oxidation catalysis
| Autor: | Junqing Yan, Yiyue Zhai, Xiangrong Ren, Shengzhong Liu, Qi Zhou |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Tafel equation
Materials science Nanoporous Non-blocking I/O Oxygen evolution Energy Engineering and Power Technology chemistry.chemical_element 02 engineering and technology Overpotential 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Catalysis Nickel Fuel Technology chemistry Chemical engineering Specific surface area Electrochemistry 0210 nano-technology Energy (miscellaneous) |
| Zdroj: | Journal of Energy Chemistry. 50:125-134 |
| ISSN: | 2095-4956 |
| Popis: | Nickel oxides and (oxy)hydroxides are promising replacements for noble-metal-based catalysts owing to their high activity and good long-term stability for the oxygen evolution reaction (OER). Herein, we developed nanoporous Ni by a method of combined rapid solidification and chemical dealloying. Subsequently, nanoporous NiO was obtained via heating treatment, the macropore and skeleton sizes of the NiO originated from Ni10Al90 alloy are 100–300 nm and 80–200 nm, respectively. Benefiting from the multi-stage nanoporous structure and high specific surface area, the nanoporous NiO demonstrates an outstanding OER, reaching 20 mA cm−2 at an overpotential of 356 mV in 1 M KOH. The corresponding Tafel slope and apparent activation energy are measured to be 76.73 mV dec−1 and 29.0 kJ mol−1, respectively. Moreover, kinetic analysis indicates that the NiO catalyst shows pseudocapacitive characteristics, and the improved current is attributed to the high-rate pseudocapacitive behavior that efficiently maintains increased nickel redox cycling to accelerate the reaction rates. After 1000 cycles of voltammetry, the overpotential of the NiO decreases by 22 mV (j = 10 mA cm−2), exhibiting excellent stability and durability. |
| Databáze: | OpenAIRE |
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