Biochemically Inspired Synthesis and Semiconductor-Integrated Interface Engineering of Metal Oxide–Graphene Nanohybrids for High-Performance, Flexible, and Next-Generation Energy Storage Systems

Addressing the urgent need for advanced energy storage technologies, this study introduces a pioneering strategy that synergistically integrates biochemically inspired synthesis with semiconductor-engineered interfaces to fabricate high-performance metal oxide–graphene nanohybrids. Metal oxides (e.g., nickel oxide) are synthesized in situ using plant-based reducing agents, offering a sustainable and eco-friendly alternative to conventional chemical methods. These oxides are uniformly anchored onto functionalized graphene oxide sheets, forming robust 2D/2D heterostructures with exceptional mechanical resilience—crucial for maintaining structural integrity under operational stress. Crucially, tailored semiconductor interlayers are strategically integrated to enhance charge transport and minimize interface resistance within the composite framework. The developed hybrids demonstrate outstanding performance metrics, including a high specific capacitance of 150 Fg⁻¹ at a current density of 0.5 A g⁻¹ and exceptional long-term stability with 96% capacitance retention over 10,000 charge–discharge cycles. Comprehensive microscopic and spectroscopic characterization unequivocally confirms uniform dispersion, effective reduction of graphene oxide, and pristine nanoscale crystallinity throughout the hybrid matrix. Beyond their exceptional electrochemical performance, these composites hold immense potential for scalable integration into flexible and wearable next-generation energy storage systems. This synergistic strategy, uniquely bridging green chemistry, advanced nanotechnology, and semiconductor engineering, not only sets a new benchmark for sustainable material design but also paves the way for fundamentally cleaner, more efficient, and truly flexible power solutions for the future.