High-performing catalysts for hydrogen evolution reaction (HER) via water electrolysis are of great importance for producing carbon-free green fuels. Compared to the routinely used metal-based systems under acidic conditions, metal-free...

MOF-derived carbon-based materials have attracted widespread attention due to their relatively large surface area, morphology, and their stability in water. Considering these advantages, these materials present themselves as excellent adsorbents. In this work, a novel method was designed for the fabrication of a nano zero-valent-iron (nZVI) carbon composite. The utilization of zinc oxide nanorods (ZnONRs) in the role of sacrificial consumable nuclei for the synthesis of MIL-53 sacrificial zinc oxide nanorods (MIL-53-SNR) and the subsequent pyrolysis at 700 °C in the inert atmosphere led to a graphitic-supported nZVI material (Fe-C-SNR). Fe-C-SNR was compared with a commercial zinc oxide bulk (MIL-53-SB) and with a pristine MIL-53. By virtue of the ZnONRs, Fe-C-SNR exhibited a greatly improved mesoporous structure. Consequently, the pyrolyzed materials were applied as adsorbents for methylene blue. Fe-C-SNR’s performance increased to more than double of the pyrolyzed MIL-53 (Fe-C), with a remarkably fast adsorption time (10 min) for a concentration of 10 mg L−1 with only 200 mg L−1 adsorbent required. This functional composite also displayed exceptional recyclability; after ten complete cycles, Fe-C-SNR was still capable of completely adsorbing the methylene blue. The utilization of ZnONRs proves itself advantageous and could further be extended to other MOFs for a wide range of applications.

Summary Perovskite‐based electrocatalysts are extensively investigated as a replacement for noble metals electrocatalysts for energy storage and conversion devices. Their interesting catalytic activity, low cost, and diversity are considered major advantages. In this work, a facile dual‐doping strategy has been conducted and yielded an astonishing upgrade of lanthanum cobaltite; fine‐tuning of both A and B sites with calcium and manganese has proven remarkably beneficial. The dual‐doping modulates the electronic configuration of both transition metals and raises the oxygen vacancies. Consequently, oxygen evolution reaction has been assessed and La0.8Ca0.2Mn0.2Co0.8O3 showed significantly improved overpotential and maximal current density in comparison with pristine LaCoO3. Furthermore, the ZAB exhibited a high open circuit potential and superior charge‐discharge cyclability, compared to Pt/C‐based electrodes. The current work explores the influence of simultaneous doping of the A and B sites in lanthanum perovskite oxides on electrocatalytic performance to encourage further exploration of such an approach in electrocatalysis. Novelty statement Simultaneous Ca and Mn dual‐doping of LaCoO3 in the A and B sites were successfully applied. The effects on the crystal structure, oxidation states, and electrocatalytic activity were studied. LCMC8228‐based ZAB has achieved a large discharge capacity of 88.1 mAh in comparison to the benchmark.

Integrated energy systems (IES) are retaining growing attention in recent years. Zn-air batteries powered water splitting devices necessitate the development of highly active and durable trifunctional electrocatalysts for oxygen evolution,...

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