Alkaline Water Splitting Using Hafnium‐Based Stable and Efficient Bifunctional Electrocatalyst

Abstract

The desire to achieve sustainable development goals inspired exploring green energy as a favorable alternative to hazardous fossil fuel‐based energy. Alkaline water electrolysis is a promising candidate for producing low‐cost pure green hydrogen; however, the efficiency of non‐precious transitional metal‐based catalysts is still behind noble electrocatalysts (like Pt and IrO2). To make hydrogen a next‐generation fuel, the replacement of high‐cost scarce noble metal is required. An attempt has been made to use a non‐precious transitional bimetallic combination of hafnium nickel diselenide/ reduced graphene oxide (HfNiSe2/rGO) for HER, OER, and overall water splitting. HfNiSe2/rGO demonstrated good electrocatalytic performance; for achieving 10 mA/cm2 of current density, the overpotential requirement is 162 mV for hydrogen evolution reaction (HER) and 320 mV for oxygen evolution reaction (OER) at 20 mA/cm2 of current density. Similarly, a low Tafel slope is required, 49 mV dec−1 for HER and 66 mV dec−1 for OER in 1 M KOH with high stability. HfNiSe2/rGO also showed highly stable activity for overall water splitting, requiring only 1.56 V to attain 10 mA/cm2 of current density. The result indicates HfNiSe2/rGO is a suitable electrocatalyst for green hydrogen generation because of its ease of production, economical, good activity, and stability towards water splitting.

Wastewater Utilization as a Source for Green Energy Generation Using Alkaline Water Splitting

“…However, their high cost and rareness have prevented further commercialization. , Hence, developing non-noble-metal-based catalysts with high activity and stability is essential. In this background, our earlier research discovered the applicability of hafnium-based transitional metal electrocatalysts with remarkable potential for alkaline water electrolysis applications. , The second challenging task is replacing pure water with wastewater for electrolysis applications. Every day, tons of wastewater are generated worldwide, and no single treatment can reduce the water’s contaminants to the permitted limits.…”

Interfacial Coupling of Graphene with Nickel Nanoparticles for Water Splitting and Urea Oxidation: A Spectroelectrochemical Investigation

“…[1][2][3][4] However, the intermittent nature of renewable sources such as solar and wind energy poses challenges for sustained utilization. [5][6][7] To address this, converting renewable energy into hydrogen for storage offers a highly efficient solution towards achieving a hydrogen-based economy. [5,6] Electrochemical water splitting emerges as a promising avenue for efficient energy conversion, encompassing two vital halfreactions: hydrogen evolution (HER) and oxygen evolution reaction (OER).…”