Cencerrero J, Sánchez P, de Lucas-Consuegra A, de la Osa A, Romero A. Influence of boron doping level and calcination temperature on hydrogen evolution reaction in acid medium of metal-free graphene aerogels.
Heliyon 2023;
9:e20748. [PMID:
37876428 PMCID:
PMC10590791 DOI:
10.1016/j.heliyon.2023.e20748]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/29/2023] [Accepted: 10/05/2023] [Indexed: 10/26/2023] Open
Abstract
In this work, metal-free boron-doped graphene-based aerogels were successfully synthesized via a one-step autoclave assembly followed by freeze-drying and used as electrocatalysts for the hydrogen evolution reaction (HER) in acidic media. The synthesized reduced graphene oxide aerogels (rGOA) showed improved electrocatalytic activity by introducing boron and structural defects. The amount of boric acid used both as a dopant and reducing agent in the synthesis was optimized (boric acid/GO mass ratio = 17.5) to practically reach the crystallization limit of boric acid (boric acid/GO mass ratio = 20). It was observed that the higher the amount of boric acid added, the more boron was incorporated into the carbonaceous structure, improving the electrocatalytic activity of the final aerogel. Furthermore, calcination of the boron-doped electrocatalyst at 600 °C resulted in final aerogels with low oxygen content, moderate surface area, bimodal pore size distribution, and a high electrochemical active surface area. The final 3D graphene aerogel developed in this work, showed such outstanding electrocatalytic activity in HER as to replace noble metal-based electrocatalysts in the future.
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