Production of H2 fuel from photocatalytic splitting of water is one of the most demanding research studies in terms of sustainable development in the energy sector. In our quest to find an effective photocatalyst for H2 production, we prepared graphene quantum dots/TiO2-based nanocomposites using a simple hydrothermal method and studied the effect of varying morphologies of TiO2 on photocatalytic H2 production. The crystal structure, morphology, surface, and optical properties were thoroughly studied by using X-ray diffraction and different spectroscopic and electron microscopic techniques. The outcome of the comparative study by using various graphene quantum dots/TiO2 nanocomposites found that P-25 TiO2-based nanocomposite gives the highest rate of H2 production among all with 29,548 μmol g–1 h–1 and is almost 14 times efficient compared to pristine P-25 TiO2. It was also evident from the characterization results that the morphology and biphasic nature of TiO2 play a crucial role in H2 production. The plausible reaction mechanism explained the dual role (cocatalyst and sensitizer) of graphene quantum dots on TiO2 nanoparticles and beneficial properties of biphasic TiO2 as an efficient charge transfer mechanism. The prepared photocatalysts also exhibited good stability, which was examined for four cycles with a time period of 4 h, making them feasible candidates for practical applications in the future.

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With a huge upsurge in the energy requirements all over the world, development of energy storage devices with high safety standards without compromising the ecological aspects has become the need of the hour, that propelled the scientific community to search for alternative yet promising sources of energy that would prevent the exhaustion of natural resources. Numerous attempts have been undertaken to utilize the renewable biopolymers in the evolution of solid‐ state electrolytes, as a substitute for liquid electrolytes which are prone to cause leakage leading to hazardous accidents. Despite strenuous efforts, it is still challenging to strike a right balance between the biopolymer elements and the conducting additives. In this review, we aim to lay out a recap on the progress achieved in recent times by employing biopolymers as electrolyte components and its future prospects, that would assist the researchers across the globe to inch one step closer in their quest to find the best electrolyte system for flexible electronics.