Recent progress in the synthesis of CuCr ₂ O ₄ nanomaterials and their composites for catalytic, energy, and biomedical applications: a state-of-the-art-review

Copper chromite nanoparticles (CuCr₂O₄ NPs) are in the spotlight of modern nanoscience due to their versatile applications across various scientific and industrial domains. This review addresses the synthesis of CuCr₂O₄ NPs, metal-doped CuCr₂O₄ NPs, and nanocomposites (NCs), emphasizing the key parameters, <i>viz</i>., reaction time, pH, temperature, precursor concentration, and the choice of fuel or surfactant, influencing their morphology, crystallinity, and functional properties. CuCr₂O₄ NPs are fabricated using several chemical methods, namely, sol-gel, co-precipitation, hydrothermal, solution combustion, and ball-milling, with different types of fuels or surfactants serving as complexing agents. These materials exhibit remarkable thermal, electrical, and catalytic characteristics. The discussion extends to their broad spectrum of applications, including biological activities such as antimicrobial, anticancer, and bone regeneration as well as their genotoxic impact. We also explore their role in photocatalysis, heterogeneous catalysis, and electrochemical applications, including supercapacitors and lithium-ion batteries. The emerging utility of CuCr₂O₄ NPs in sensor development is also highlighted. This review covers the recent advancements in the synthesis of CuCr₂O₄ NPs, highlighting their key challenges and future directions. Analyzing the structure-property relationships and the influence of synthesis parameters on their performance provides valuable insights into optimizing the design and functionalization of CuCr₂O₄ NPs for specific applications.