Controlled Synthesis of Nickel Phosphides in Hollow N, P Co-Doped Carbon: In Situ Transition to (Oxy)hydroxide Phases During Oxygen Evolution Reaction
Developing sustainable and efficient electrocatalysts for the oxygen evolution reaction (OER) is crucial for advancing energy storage technologies. This study explored the dual role of phosphorus as a dopant in carbon matrices and a key component in nickel phosphides (Ni<inf>2</inf>P and...
| Authors: | , , , , , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2025 |
| Country: | España |
| Institution: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repository: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/419754 |
| Online Access: | http://hdl.handle.net/10261/419754 https://www.scopus.com/inward/record.uri?eid=2-s2.0-105001271300&doi=10.3390%2Fcatal15030292&partnerID=40&md5=11c89e4119373391cd68e2e968acc4a2 |
| Access Level: | Open access |
| Keyword: | co-doped carbon electrocatalyst hollow nanostructures nickel phosphide oxygen evolution reaction polydopamine solvothermal method |
| Summary: | Developing sustainable and efficient electrocatalysts for the oxygen evolution reaction (OER) is crucial for advancing energy storage technologies. This study explored the dual role of phosphorus as a dopant in carbon matrices and a key component in nickel phosphides (Ni<inf>2</inf>P and Ni<inf>12</inf>P<inf>5</inf>), synthesized using dopamine (PDA) and ammonium phosphate as eco-friendly precursors. The phase formation of nickel phosphides was found to be highly dependent on the P/PDA ratio (0.15, 0.3, 0.6, and 0.9), allowing for the selective synthesis of Ni<inf>2</inf>P or Ni<inf>12</inf>P<inf>5</inf>. Operando Raman spectroscopy revealed that both phases undergo surface transformation into nickel (oxy)hydroxide species under OER conditions, yet Ni<inf>2</inf>P-based catalysts demonstrated superior activity and long-term stability. This enhancement is attributed to efficient electron transfer at the dynamic Ni<inf>2</inf>P/NiOOH interface. Additionally, hollow nanostructures formed at intermediate P/PDA ratios (≤0.3) via the Kirkendall effect and Ostwald ripening contributed to an increased specific surface area and micropore volume, further improving the catalytic performance. Electrochemical impedance spectroscopy confirmed reduced interfacial resistance and enhanced charge transport. These findings offer new insights into the rational design of high-performance electrocatalysts and propose a green, tunable synthesis approach for advanced energy conversion applications. © 2025 by the authors. |
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