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Synergistic Effects in N,O‐Comodified Carbon Nanotubes Boost Highly Selective Electrochemical Oxygen Reduction to H(2)O(2)

Electrochemical 2‐electron oxygen reduction reaction (ORR) is a promising route for renewable and on‐site H(2)O(2) production. Oxygen‐rich carbon nanotubes have been demonstrated their high selectivity (≈80%), yet tailoring the composition and structure of carbon nanotubes to further enhance the sel...

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Detalles Bibliográficos
Autores principales: Xu, Shuhui, Lu, Ruihu, Sun, Kai, Tang, Jialun, Cen, Yaping, Luo, Liang, Wang, Ziyun, Tian, Shubo, Sun, Xiaoming
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley and Sons Inc. 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9507382/
https://www.ncbi.nlm.nih.gov/pubmed/35901499
http://dx.doi.org/10.1002/advs.202201421
Descripción
Sumario:Electrochemical 2‐electron oxygen reduction reaction (ORR) is a promising route for renewable and on‐site H(2)O(2) production. Oxygen‐rich carbon nanotubes have been demonstrated their high selectivity (≈80%), yet tailoring the composition and structure of carbon nanotubes to further enhance the selectivity and widen working voltage range remains a challenge. Herein, combining formamide condensation coating and mild temperature calcination, a nitrogen and oxygen comodified carbon nanotubes (N,O‐CNTs) electrocatalyst is synthesized, which shows excellent selective (>95%) H(2)O(2) selectivity in a wide voltage range (from 0 to 0.65 V versus reversible hydrogen electrode). It is significantly superior to the corresponding selectivity values of CNTs (≈50% in 0–0.65 V vs RHE) and O‐CNTs (≈80% in 0.3–0.65 V vs RHE). Density functional theory calculations revealed that the C neighbouring to N is the active site. Introducing O‐related species can strengthen the adsorption of intermediates *OOH, while N‐doping can weaken the adsorption of in situ generated *O and optimize the *OOH adsorption energy, thus improving the 2‐electron pathway. With optimized N,O‐CNTs catalysts, a Janus electrode is designed by adjusting the asymmetric wettability to achieve H(2)O(2) productivity of 264.8 mol kg(cat) (–1) h(–1).