Zineb Hammi

Cost-effective, durable, and environmentally friendly electrocatalysts to be used for the alkaline hydrogen evolution reaction (HER) represent one of the key challenges facing green hydrogen generation. In this context, a TiO₂-doped hydrochar derived from Phoenix dactylifera L. Deglet Nour (date pits) was synthesized and incorporated into a graphite-based electrode to improve HER performance in a 1 M KOH solution. Three TiO₂ loadings (1, 3, and 6 wt%) were systematically studied and compared using electrochemical techniques to evaluate the influence of oxide incorporation on HER kinetics. In parallel, physicochemical characterization analyses were performed to acquire an in-depth understanding of the morphology, composition, and surface properties of biomass-derived carbonaceous materials and to establish correlations with their electrochemical behavior. The G/HC-3% TiO₂ electrode exhibited the most pronounced electrocatalytic performance, with an overpotential of 194 mV at −10 mA·cm⁻² and a Tafel slope of 67 mV·dec⁻¹, indicating favorable interfacial charge transfer kinetics. The present work demonstrates that biomass-derived TiO₂-doped hydrochar has significant potential as a sustainable and high-performance electrocatalyst in alkaline water electrolysis.

A novel electrochemically sensitive sensor has been developed based on Hydrochar derived from Phoenix dactylifera was prepared for the detection of Methylene Blue (MB). These hydrochar (HC) have been used for the modification of the glassy carbon electrode (GCE). This electrode was characterized by scanning electron microscopy (SEM). The electrochemical properties of MB in the modified electrode (HC/GCE) were studied by square-wave voltammetry (SWV) and cyclic voltammetry (CV) under optimized conditions. Owing to a synergistic effect, the HC/GCE exhibited an obvious electrocatalytic effect on positively charged MB. The influence of experimental variables (accumulation time, supporting electrolyte, pH) was studied. Under optimized conditions, the constructed sensor illustrated a linear voltammetric curve for the MB in the concentration interval from 10-4M to 10-10M, with a detection limit of 0.2nM. A study of the effect of interference on sensor functionality was carried out, as well as an analysis of MB recovery in real wastewater samples. The modified electrode offers numerous advantages, including easy preparation, low detection limit, high sensitivity, good repeatability, short response time and an effective detection platform for MB in wastewater.