Purnami Purnami, Willy Satrio Nugroho, Wresti L. Anggayasti, N.M. Dwidiani, I.N.G. Wardana
Organic electrocatalyst is a promising solution to support metal-free green hydrogen production. Dexa's Laboratory of Biomolecular Sciences (DLBS-1033) as a L. Rubellus worm derived protein based bio-organic electrocatalyst has shown remarkable stability. However, the location of its active sites has not been understood. This study aims to understand the surface reaction of DLBS-1033 bio-organic by mapping the active sites through Crystallographic technique. The active sites mapping was performed based on electron density using Fourier synthesis method from X-ray diffraction (XRD) data. The structure and performance confirmation through also have been performed to relate the kinetics with surface reaction. This study found the active sites of DLBS-1033 is a catalytic triad comprises of imidazole ring containing histidine, negatively charged aspartate, and polar nucleophilic serine. The active sites contribute to hydrogen evolution reaction (HER) are at high electron density area. However, the polar area with lower electron density accounts for water molecules binding which increases the surface area reaction of the bound water molecules. Both active sites cooperates at the interface with electrolyte to weakens water intermolecular bond by provide electrostatic shear stress. Therefore, DLBS-1033 is a bio-organic electrocatalyst with multi-role dual active sites. © 2025 Elsevier B.V.
Department of Mechanical Engineering, Brawijaya University, Ketawanggede, Lowokwaru, Jawa Timur, Malang, 65145, Indonesia; Brawijaya University, Ketawanggede, Lowokwaru, Jawa Timur, Malang, 65145, Indonesia; Department of Mechanical Engineering, Udayana University, Jl. Raya Kampus Unud Blok r, Jimbaran, Kuta Selatan, Bali, Badung, 80361, Indonesia
