Coffee waste-derived porous carbon for hydrogen and oxygen evolution reaction

• Published in: Chemical physics impact Vol. 6; p. 100175
• Main Authors: Pandey, Keshab, Jeong, Hae Kyung
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-06-2023; Elsevier
• Subjects: Coffee waste; Electrocatalyst; Hydrogen evolution reaction; Oxygen evolution reaction; Hydrogen evolution reaction; Electrocatalyst; Oxygen evolution reaction; Coffee waste
• ISSN: 2667-0224; 2667-0224
• DOI: 10.1016/j.chphi.2023.100175

Porous carbon was synthesized from coffee waste for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The coffee waste was carbonized at 600 °C for 2 hrs and activated at 500, 600, and 700 °C, respectively. The activated coffee waste at 600 °C exhibits lower overpotential of -210 mV at -10 mA cm−2 and 230 mV at 10 mA cm−2 with lower Tafel slopes of 120 mV dec−1 and 140 mV dec−1 for HER and OER, respectively, compared to the samples at different activated temperature. The better HER and OER performances are associated to high electroactive surface area (3.9 × 10−5 cm2) and low charge transfer resistance (39 Ω) of the 600 °C activated sample, which also shows interconnected porous structure, in comparison with the other samples. The coffee waste after the carbonization and activation could be applied for HER and OER electrocatalyst.
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