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...

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Detalles Bibliográficos
Autores: Ríos Ruiz, D., Arévalo Cid, Pablo, Cebollada Borao, Jesús, Celorrio, V., Haeussler, M., Drev, S., Martínez Huerta, M. Victoria
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/419754
Acceso en línea: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:acceso abierto
Palabra clave:co-doped carbon
electrocatalyst
hollow nanostructures
nickel phosphide
oxygen evolution reaction
polydopamine
solvothermal method
Descripción
Sumario: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.