Alongside rare‐earth metals, Ni, Fe, Co, Cu are some of the critical materials that will be in huge demand thanks to growth in clean‐energy sector. Herein scrap stainless steel wires (SSW) from worn‐out tires are employed as a support material for catalyst integration in the hydrogen evolution reaction (HER). In addition, SSW by corrosion engineering is exercised as an in situ formed freestanding robust electrode for the oxygen evolution reaction (OER). By superficial corrosion of SSW, inherent active species are unmasked in the form of Ni/FeOOH nanocrystallites displaying efficient water oxidation by reaching 500 mA cm−2 at low overpotential (η500) of 287 mV in 1 m KOH. Similarly, cathode scrap SSW with active (alloy) coatings of MoNi4 catalyzes the HER at η‐200 = 77 mV, with a low activation energy (Ea = 16.338 kJ mol−1) and high durability of 150 h. Promisingly, when used in industrial conditions, 5 m KOH, 343 K, these electrodes demonstrate abnormal activity by yielding high anodic and cathodic current density of 1000 mA cm−2 at η = 233 mV and η = 161 mV, respectively. This work may inspire researchers to explore and reutilize high‐demand metals from scrap for addressing critical material shortfalls in clean‐energy technologies.

Disposal of e‐wastes in prescribed landfills poses serious environmental concerns at both a local and global scale. Recovering valuable materials from e‐wastes and utilizing them for development of eco‐design devices guides one to a more productive way of managing wastes. Recycled copper is capable of retaining its intrinsic properties and can be reused with same expectation of performances; capitalizing on this fact, herein, it is attempted to utilize copper from e‐waste as an economically viable catalytic substrate for overall water splitting. Upon deposition of amorphous nickel cobalt phosphide films, the scrap copper wires are highly efficient for catalyzing hydrogen and oxygen evolution reaction at low overpotential (10η‐HER = 178 mV, 10η‐OER = 220 mV), and considerably promote water catalysis at 1.59 V@10 mA cm−2. Moreover, the electrodes demonstrate long‐term stability in alkaline electrolyte that can potentially be employed for large‐scale electrolyzer application. The proposed electrode architecture, by the explicit growth of bimetallic phosphide on highly conductive Cu substrate, facilitates fast electron transport and promises a minimum contact resistance between electrocatalyst and current collector. This work paves the way for development of environmentally sound electrode materials from e‐waste that can be exercised for a myriad of other clean energy reactions.

For industrial-scale water electrolysis, development of a highly stable and active oxygen evolution reaction (OER) electrocatalyst is highly demanded. In this study, we report an efficient OER electrocatalyst of CeO x (unary oxide) and NiFe-OH (bimetallic hydroxide) electrochemically deposited on a macroporous nickel foam substrate. The synthesized electrocatalyst exhibits remarkably improved OER performance by reaching a current density of 100 mA cm −2 at a low overpotential of 280 mV, which is quite superior to that of most of the previously reported non-noble-metalbased OER electrocatalysts. Furthermore, the developed catalyst demonstrated a minor Tafel slope of 43.2 mV dec −1 with good stability under a large current at a continuous operation of 80 000 s in a strong alkaline electrolyte. Experimental observations revealed that the combination of CeO x and NiFe-OH accelerates the electroadsorption energies between the electrocatalyst surface and oxygen intermediates, considerably contributing to the OER enhancement. These results undoubtedly represent an important milestone toward the development of efficient OER electrocatalysts for applications as industrial water electrolyzers.