Synthesis and characterization of sol-gel processed GO/NiO hybrid composites for gas sensing and photocatalytic applications

This study focused on synthesizing and characterizing a hybrid composite of graphene oxide (GO) and nickel oxide (NiO) prepared by a sol-gel technique. The nanocomposite was characterized to investigate the structural, morphological, optical, chemical, electrical, photocatalytic, and gas-sensing properties via diverse techniques. These characterizations produced prominent crystalline peaks, a direct energy band gap value of 1.76 eV, characteristic absorption bands, and even distributed nanopebbles. The electrical and gas sensing measurements were conducted at 10 V and 100 ppm concentration under exposure to a liquefied petroleum gas (LPG). The composites showed high sensitivity to LPG at an operating temperature of 400 °C. Upon further exposure to methylene blue at an illumination intensity of 80 W/m², the composites exhibited more than 90 percent photocatalytic efficiency over a degradation period of 120 min. These results highlight the multifunctional capabilities of the synthesized hybrid nanocomposites, suggesting promising applications in gas sensing and photocatalytic degradation processes.

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