Metal oxide semiconductors (MOS) have proven to be most powerful sensing materials to detect hydrogen sulfide (H 2 S), achieving part per billion (ppb) level sensitivity and selectivity. However, there has not been a way of extending this approach to the top-down H 2 S sensor fabrication process, completely limiting their commercial-level productions. In this study, we developed a top-down lithographic process of a 10 nm-scale SnO 2 nanochannel for H 2 S sensor production. Due to high-resolution (15 nm thickness) and high aspect ratio (>20) structures, the nanochannel exhibited highly sensitive H 2 S detection performances (R a /R g = 116.62, τ res = 31 s at 0.5 ppm) with selectivity (R Hd 2 S /R acetone = 23 against 5 ppm acetone). In addition, we demonstrated that the nanochannel could be efficiently sensitized with the p−n heterojunction without any postmodification or an additional process during one-step lithography. As an example, we demonstrated that the H 2 S sensor performance can be drastically enhanced with the NiO nanoheterojunction (R a /R g = 166.2, τ res = 21 s at 0.5 ppm), showing the highest range of sensitivity demonstrated to date for state-of-the-art H 2 S sensors. These results in total constitute a high-throughput fabrication platform to commercialize the H 2 S sensor that can accelerate the development time and interface in real-life situations.

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The design of new nanomaterials for rapid and reversible detection of molecules in existence is critical for real-world sensing applications. Current nanomaterial libraries such as carbon nanotubes, graphene, MoS2, and MXene are fundamentally limited by their slow detection speed and small signals; thus, the atomic-level material design of molecular transport pathways and active binding sites must be accompanied. Herein, we fully explore the chemical and physical properties of a hydrogen-substituted graphdiyne (HsGDY) for its molecular sensing properties. This new carbon framework comprises reactive sp carbons in acetylenic linkages throughout the 16.3 Å nanopores and allows for detecting target molecules (e.g., H2) with an exceptionally high sensitivity (ΔR/R b = 542%) and fast response/recovery time (τ90 = 8 s and τ10 = 38 s) even without any postmodification process. It possesses 2 orders of magnitude higher sensing ability than that of existing nanomaterial libraries. We demonstrate that rapid and reversible molecular binding is attributed to the cooperative interaction with adjacent double sp carbon in the layered nanoporous structure of HsGDY. This new class of carbon framework provides fundamental solutions for nanomaterials in reliable sensor applications that accelerate real-world interfacing.