Two-dimensional ultrathin Co3O4 nanosheet: A cost-effective and reusable catalyst for hydrogen production via sodium borohydride methanolysis

Author(s)

Leite, Ramon Resende ; de Souza, Dilean Theilon Dutra ; Amaral, Mateus de Souza ; Bernardi, Maria Ines Basso ; Fajardo, Humberto Vieira

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF HYDROGEN ENERGY; v. 124, p. 14-pg., 2025-05-01.

Abstract

This study presents an innovative green synthesis strategy for hierarchical nanoparticles comprising twodimensional (2D) cobalt oxide (Co3O4) nanosheets, using microfibrillated cellulose as a sustainable template. The synthesized material was used for the first time as a catalyst in hydrogen (H2) production through sodium borohydride (NaBH4) methanolysis. A comprehensive investigation utilizing a full factorial design (23) was conducted to assess the effects of catalyst mass, NaBH4 concentration, and reaction temperature. Under optimal conditions, i.e., at 55 degrees C with 10 mg of catalyst and 0.193 g of NaBH4, the maximum hydrogen generation rate (HGR) reached an impressive 21,128 mL min-1 g-1. This HGR value was approximately 15 times greater than the results obtained in experiments conducted at room temperature (25-30 degrees C). The catalyst showed a relatively low activation energy (Ea = 19.5 +/- 0.2 kJ mol-1). Although a 25 % activity loss occurred after the first cycle, the activity remained stable throughout the fifth cycle. Ex situ Fourier-transformed infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses revealed that the surface chemistry changed after use, thus contributing to a reduction in catalytic activity. (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC