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Gas-phase surface-enhanced Raman scattering (SERS) remains challenging due to poor analyte affinity to SERS substrates. The reported use of capturing probes suffers from concurrent inconsistent signals and long response time due to the formation of multiple potential probe-analyte interaction orientations. Here, we demonstrate the use of multiple non-covalent interactions for ring complexation to boost the affinity of small gas molecules, SO2 and NO2 , to our SERS platform, achieving rapid capture and multiplex detection down to 100 ppm. Experimental and in-silico studies affirm stable ring complex formation, and kinetic investigations reveal a 4-fold faster response time compared to probes without stable ring complexation capability. By synergizing spectral concatenation and support vector machine regression, we achieve 91.7 % accuracy for multiplex quantification of SO2 and NO2 in excess CO2 , mimicking real-life exhausts. Our platform shows immense potential for on-site exhaust and air quality surveillance. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) Submitted/Accepted version This research is supported by Singapore National Research Foundation Central Gap Fund (NRF2020NRF-CG001-010) and A*STAR AME Individual Research Grant (A20E5c0082).

The electrochemical nitrogen reduction reaction (NRR) offers a sustainable solution towards ammonia production but suffers poor reaction performance owing to preferential catalyst–H formation and the consequential hydrogen evolution reaction (HER). Now, the Pt/Au electrocatalyst d-band structure is electronically modified using zeolitic imidazole framework (ZIF) to achieve a Faradaic efficiency (FE) of > 44% with high ammonia yield rate of > 161 mgmgcat @1 h @1 under ambient conditions. The strategy lowers electrocatalyst d-band position to weaken H adsorption and concurrently creates electron-deficient sites to kinetically drive NRR by promoting catalyst–N2 interaction. The ZIF coating on the electrocatalyst doubles as a hydrophobic layer to suppress HER, further improving FE by > 44-fold compared to without ZIF (ca. 1%). The Pt/Au-NZIF interaction is key to enable strong N2 adsorption over H atom. Ministry of Education (MOE) Nanyang Technological University This research is supported by the Ministry of Education, Singapore, under Tier 1 (RG11/18) and Tier 2 (MOE2016-T2- 1-043) grants, and Max Planck Institute-Nanyang Technological University Joint Lab. H.Y.F.S., C.S.L.K. and G.C.P.-Q. thank scholarship support from Nanyang Technological University, Singapore. J.R.T.C. and J.Y.P. thank CN Yang scholarship. H.K.L. thanks the International Postdoctoral Scholarship support from Nanyang Technological University, Singapore, and Singapore Ministry of Education. We thank Mr. Poh Chong Lim, A*STAR, for XRD analysis.

Gas‐liquid reactions form the basis of our everyday lives, yet they still suffer poor reaction efficiency and are difficult to monitor in situ, especially at ambient conditions. Herein, we drive an inert gas‐liquid reaction between aniline and CO2 at 1 atm and 298 K by selectively concentrating these immiscible reactants at the interface between metal‐organic framework and solid nanoparticles (solid@MOF). Real‐time reaction SERS monitoring and simulation investigations affirm the formation of phenylcarbamic acid, which was previously undetectable because they are unstable for post‐reaction treatments. The solid@MOF ensemble gives rise to a >28‐fold improvement to reaction efficiency as compared to ZIF‐only and solid‐only platforms, emphasizing that the interfacial nanocavities in solid@MOF are the key to enhance gas‐liquid reaction. Our strategy can be integrated with other functional materials, hence opens up new opportunities for ambient‐operated gas‐liquid applications. MOE (Min. of Education, S’pore) Accepted version

Liquid marbles are emergent microreactors owing to their isolated environment and the flexibility of materials used. Plasmonic liquid marbles (PLMs) are demonstrated as the smallest spectroelectrochemical microliter‐scale reactor for concurrent spectro‐ and electrochemical analyses. The three‐dimensional Ag shell of PLMs are exploited as a bifunctional surface‐enhanced Raman scattering (SERS) platform and working electrode for redox process modulation. The combination of SERS and electrochemistry (EC) capabilities enables in situ molecular read‐out of transient electrochemical species, and elucidate the potential‐dependent and multi‐step reaction dynamics. The 3D configuration of our PLM‐based EC‐SERS system exhibits 2‐fold and 10‐fold superior electrochemical and SERS performance than conventional 2D platforms. The rich molecular‐level electrochemical insights and excellent EC‐SERS capabilities offered by our 3D spectroelectrochemical system are pertinent in charge transfer processes. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Nanyang Technological University National Research Foundation (NRF) Accepted version X.Y.L. thanks the financial support from National Research Foundation, Singapore (NRF-NRFF2012-04), Singapore Ministry of Education, Tier 1(RG21/16) and Tier (MOE2016-T2-1-043 (S)) grants, and Nanyang Technological University.C.S.L.K.,G.C.P.-Q., and M.R.L. acknowledge support from Nanyang Presidential Graduate Scholarship. H.K.L. thanks the graduate scholarship from A*STAR, Singapore