▎ 摘　　要

Here, for the first time, we synthesize hybrid hydrophilic and hydrophobic nanocarbon materials with reliable and stable gas sensing performance. The hybrid monolayer graphene (Gr)enitrogen and argon (N-2 and Ar) gas incorporated ultra-nanocrystalline diamond (Gr/N-2@UNCD and Gr/Ar@UNCD) structures were synthesized using a microwave plasma enhanced chemical vapor deposition (MPECVD) method. The presented nanohybrid combinations have a unique morphology with diamond defects (sp(3)) covered by a graphene sheet (sp(2)). Sample sensors with metal electrodes were fabricated to study the H-2 gas sensing properties of the material. Thus, the as-fabricated Gr/N-2@UNCD exhibited higher sensor response (14.6%) than those of the as-fabricated Gr, N-UNCD and Gr/Ar@UNCD (3.6, 1.07 and 11.2%) based devices. The Gr/N-2@UNCD nanohybrid based sensor showed outstanding repeatability, selectivity and stability over similar to 56 days. The substantial improvement in the H-2 sensing performance of the as-fabricated Gr/N-2@UNCD nanohybrid based sensor was attributed to the modifications in surface morphology and resistance. The partial-hydrophobic surface of Gr/N-2@UNCD alters the beneficial resistivity and improved absorption, which assists in the efficient transport of electrons and H-2 gas molecules. The hybrid nanostructure of Gr-N-2@UNCD exhibits several unique properties that paves the way to future opportunities for advanced gas sensor fabrication. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.