Ag₂S-Sensitized NiO–ZnO Heterostructures with Enhanced Visible Light Photocatalytic Activity and Acetone Sensing Property

Abstract

Visible light-driven Ag 2 S-grafted NiO–ZnO ternary nanocomposites are synthesized using a facile and cost-effective homogeneous precipitation method. The structural, morphological, and optical properties were extensively studied, confirming the formation of ternary nanocomposites. The surface area of the synthesized nanocomposites was calculated by electrochemical double-layer capacitance ( C dl ). Ternary Ag 2 S/NiO–ZnO nanocomposites showed excellent visible light photocatalytic property which increases further with the concentration of Ag 2 S. The maximum photocatalytic activity was shown by 8% Ag 2 S/NiO–ZnO with a RhB degradation efficiency of 95%. Hydroxyl and superoxide radicals were found to be dominant species for photodegradation of RhB, confirmed by scavenging experiments. It is noteworthy that the recycling experiments demonstrated high stability and recyclable nature of the photocatalyst. Moreover, the electrochemical results indicated that the prepared nanocomposite exhibits remarkable activity toward detection of acetone. The fabricated nanocomposite sensor showed high sensitivity (4.0764 μA mmol L –1 cm –2 ) and a lower detection limit (0.06 mmol L –1 ) for the detection of acetone. The enhanced photocatalytic and the sensing property of Ag 2 S/NiO–ZnO can be attributed to the synergistic effects of strong visible light absorption, excellent charge separation, and remarkable surface properties.

Manganese-Doped Zinc Oxide Nanostructures as Potential Scaffold for Photocatalytic and Fluorescence Sensing Applications

“…[38,39]. The immense use of ZnO can be observed in photocatalysts, catalysts, and antibacterial agents, due to its biocompatibility, non-toxic, and excellent redox properties [40,41]. The doping of transition metals (e.g., Co, Mn, Fe, Ni, and Cu) onto ZnO improves its optical and electrical properties [42,43].…”

Eco-Friendly Fluorescent Carbon Nanodots: Characteristics and Potential Applications

“…However, due to poor electron transfer inside the carbon nanodots, the application has been impeded. In order to increase the efficiency of carbon nanodots and to make them better photocatalysts, their electronic structure is modified by adopting several strategies namely, metal ion doping, heterostructure formation, composite formation, and so on [8,95]. Doped carbon nanodots show efficient electronic properties with a strong visible light absorption and show low recombination of charge carriers [96].…”

“…Since then, there have been a considerable increase in the interest of researchers to fabricate carbon-based fluorescent quantum dots, which can substitute the toxic and unstable metallic-based quantum dots (CdS, CdSe, CdTe, PbS, etc.). The fluorescent carbon nanodots possess many advantages over classical quantum dots in terms of biocompatibility, stability, solubility, inertness, cytotoxicity, drug delivery, and synthesis [7,8]. In addition to that, carbon nanodots do not show photobleaching or blinking effects.…”

Ferrite Nanocomposite Based Electrochemical Sensor: Characterization, Voltammetric and Amperometric Studies for Electrocatalytic Detection of Formaldehyde in Aqueous Media

“…Ag 2 S is a low band chalcogenide with very high absorption coefficient exhibits wide variety of applications in diverse fields [26]. Owing to its efficient and excellent photooxidative and electronic properties, Ag 2 S has been used in several fields like IR detectors, photography, photocatalysis and electrochemical sensing [28, 29]. Moreover, Ag 2 S possesses good chemical stability and negligible toxicity in contrast to other narrow band semiconductors.…”