Electrospun carbon nanofibers (CNF) with surfaceanchored bimetallic gold−platinum nanoislands (CNFs@Au−Pt NIs) have been effectively developed by electrospinning and chemical reduction methods, and its enhanced trace-level hydrogen gas sensing characteristics at room temperature have been explored. Structural and morphological properties of the CNFs@platinum NIs (CNFs@Pt NIs) and CNFs@gold−platinum NIs (CNFs@ Au−Pt NIs) have been characterized using X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy analyses, which showed the successful formation of bimetallic Au−Pt NIs homogeneously distributed over the surface of CNFs. The bimetallic Au−Pt NIs on CNFs provide superior hydrogen gas sensing properties toward wide range detection of hydrogen gas from 0.01 to 4% under ambient conditions. Desorption of hydrogen from the nanohybrids without any delay is possible as the chemisorbed hydrogen on Pt has been compensated with the integration of Au on CNFs leading to rapid response and recovery time. Adsorption kinetics studies indicate that the adsorption of hydrogen occurs on active Au−Pt bimetallic sites because of the work function differences leading to changes in the resistance. In situ Raman spectroscopic analysis revealed the interaction of hydrogen (H 2 ) gas with the catalytic active NIs at room temperature, and a plausible mechanism has been proposed. This bimetallic catalyst functionalized CNFs can be considered as a potential candidate for the development of high-performance gas sensors with fast recovery and amplified response toward tracelevel hydrogen gas for real time applications.

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Porous n–p type ultra-long ZnO@Bi2O3 heterojunction nanorods have been synthesized through a solvothermal method and their complex charge transport characteristics pertaining to NO2 gas sensing properties have been investigated.

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Herein, n-n type one dimensional ZnO@In2O3 heterojunction nanowires have been developed and its localized electron transfer properties during trace-level NO2 gas sensing process have been probed at room-temperature. Solvothermally synthesized...

Flexible electronic gas sensors working at room temperature have acquired enormous attention in recent years due to their suitability to be integrated into various wearable electronic products. In this investigation, we have demonstrated a H 2 gas sensor using less platinum bimetallic nickel−platinum nanocatalyst-functionalized carbon nanofibers (CNFs@Ni−Pt) fabricated on a flexible platform. The flexible CNF@Ni−Pt sensor showed only a negligible decrease in response during mechanical stress under flat (21%) and bent (17%) states after several bending cycles owing to the high aspect ratio of the carbon nanofiber network, which helps us to indulge a long bending path. Moreover, the flexible CNF@Ni−Pt sensor showed superior sensor response (50%) toward H 2 with outstanding selectivity toward other interfering gases. In addition, hydrogen adsorption kinetic studies performed on flexible CNF@Ni−Pt sensors indicated comparable theoretically calculated (0.42) and experimental (0.49) rate constant values. In situ Raman spectroscopy analysis aided in unraveling the H 2 interaction with the catalytically active Ni−Pt sites anchoring on the surface of CNFs, and a plausible sensing mechanism could be predicted. Flexible, less platinum CNF@Ni−Pt sensors can find wider applications in the fields of flexible electronics, biomedical, and environmental monitoring.

Production and alignment of heterojunction metal oxide semiconductor nanomaterials-based sensing elements for microsensor devices has always posed fabrication challenges since it involves multi-step synthesis processes. Herein, we demonstrate a coaxial...

Aligned 1D heterojunction carbon nanofibers have been developed, which possess exceptional properties like high surface-to-volume ratio and excellent direct electron transport properties favouring their hydrogen sensing properties.