In-situ growth of nonstoichiometric CrO0.87 and Co3O4 hybrid system for the enhanced electrocatalytic water splitting in alkaline media

• Published in: International journal of hydrogen energy 2023-12, Vol.48 (93), p.36439-36451
• Main Authors: Solangi, Muhammad Yameen, Aftab, Umair, Tahira, Aneela, Hanan, Abdul, Montecchi, Monica, Pasquali, Luca, Tonezzer, Matteo, Mazzaro, Raffaello, Morandi, Vittorio, Laghari, Abdul Jaleel, Nafady, Ayman, Abro, Muhammad Ishaq, Emo, Melanie, Vigolo, Brigitte, Dawi, Elmuez, Mustafa, Elfatih, Ibupoto, Zafar Hussain
• Format: Article
• Language: English
• Subjects: Chemical Sciences; CrO0.87 and Co3O4 hybrid material; Nonstoichiometric growth; Oxygen evolution reaction
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2023.06.059

The development of electrocatalysts for electrochemical water splitting has received considerable attention in response to the growing demand for renewable energy sources and environmental concerns. In this study, a simple hydrothermal growth approach was developed for the in-situ growth of non-stoichiometric CrO0.87 and Co3O4 hybrid materials. It is apparent that the morphology of the prepared material shows a heterogeneous aggregate of irregularly shaped nanoparticles. Both CrO0.87 and Co3O4 have cubic crystal structures. Its chemical composition was governed by the presence of Co, Cr, and O as its main constituents. For understanding the role CrO0.87 plays in the half-cell oxygen evolution reaction (OER) in alkaline conditions, CrO0.87 was optimized into Co3O4 nanostructures. The hybrid material with the highest concentration of CrO0.87 was found to be highly efficient at driving OER reactions at 255 mV and 20 mA cm−2. The optimized material demonstrated excellent durability for 45 h and a Tafel slope of 56 mV dec−1. Several factors may explain the outstanding performance of CrO0.87 and Co3O4 hybrid materials, including multiple metallic oxidation states, tailored surface properties, fast charge transport, and surface defects. An alternative method is proposed for the preparation of new generations of electrocatalysts for the conversion and storage of energy. •Hydrothermally non-stoichiometric CrO0.87 and Co3O4 hybrid system was prepared.•CrO0.87 and Co3O4 hybrid system showed an enhanced OER activity.•A low overpotential for OER reaction was about 255 mV at 20 mA/cm2.•The CrO0.87 and Co3O4 hybrid system was highly durable for 45 h.