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Understanding water activation and reaction at metal-oxide interfaces is of significant importance. However, it remains a great challenge due to the weak signal of surface-active species and the difficulties associated with in situ detection methods. Herein, the water-gas shift reaction mechanism at the Pd–CeO2 interfaces has been systematically studied by using the "borrowing" surface-enhanced Raman spectroscopy (SERS) strategy through the fabrication of Au@CeO2–Pd core–shell satellite structures. Through the combination of in situ SERS and online mass spectrometry, real-time monitoring of surface intermediate species and reaction products is achieved simultaneously. It is found that CO adsorbed on Pd can either react with the oxygen species formed via water dissociation (the associative mechanism) or the lattice oxygen in CeO2 (the redox mechanism), with the former having a higher activity. This work provides an effective approach for the in situ study of interfacial catalysis and explains the important role of the Pd–CeO2 interfaces in the water-gas shift reaction at a molecular level. [ABSTRACT FROM AUTHOR]

Developing efficient oxygen evolution reaction (OER) electrocatalysts can greatly advance the commercialization of proton exchange membrane (PEM) water electrolysis. However, the unclear and disputed reaction mechanism and structure‐activity relationship of OER pose significant obstacles. Herein, the active site and intermediate for OER on AuIr nanoalloys are simultaneously identified and correlated with the activity, through the integration of in situ shell‐isolated nanoparticle‐enhanced Raman spectroscopy and X‐ray absorption spectroscopy. The AuIr nanoalloys display excellent OER performance with an overpotential of only 246 mV to achieve 10 mA cm−2 and long‐term stability under strong acidic conditions. Direct spectroscopic evidence demonstrates that *OO adsorbed on IrOx sites is the key intermediate for OER, and it is generated through the O–O coupling of adsorbed oxygen species directly from water, providing clear support for the adsorbate evolution mechanism. Moreover, the Raman information of the *OO intermediate can serve as a universal "in situ descriptor" that can be obtained both experimentally and theoretically to accelerate the catalyst design. It unveils that weakening the interactions of *OO on the catalysts and facilitating its desorption would boost the OER performance. This work deepens the mechanistic understandings on OER and provides insightful guidance for the design of more efficient OER catalysts. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Core‐shell nanostructures constituted by a plasmonic core and an ultrathin shell have drawn enormous attentions in enhanced spectroscopies, catalysis, energy, and other fields because of their splendid properties such as multifunctionality, stability, and adjustability. In this article, we summarized the endeavors made by our group in the past decade about the core‐shell nanostructures in the shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS) and plasmon‐enhanced spectroscopies. Meanwhile, the potential challenges and perspectives about core‐shell nanostructures in spectroscopies have also been proposed. Thus, we believe this article would provide an avenue for a comprehensive understanding of enhanced spectroscopies with core‐shell nanostructures. What is the most favorite and original chemistry developed in your research group?? Core‐shell nanostructure enhanced Raman spectroscopy for surface analysis. How do you get into this specific field? Could you please share some experiences with our readers?? I started the studies on Raman spectroscopy since I was a Ph.D. candidate. I think most researchers should concentrate on specific fields, especially those that can hardly be solved by others, and make constant research on them. How do you supervise your students?? First, give highly challenging or unique topics to students. Then, make detailed plans for them and supervise them to execute the plans. What is the most important personality for scientific research?? Insistence and diligence. What are your hobbies? What's your favorite book(s)? Playing computer games. My favorite book is State of Divinity (笑傲江湖), by Louis Cha. What is your favorite journal(s)? The journals report systematic and pioneer works on chemistry, materials, or energy, etc. [ABSTRACT FROM AUTHOR]

The spillover of hydrogen species and its role in tuning the activity and selectivity in catalytic hydrogenation have been investigated in situ using surface‐enhanced Raman spectroscopy (SERS) with 10 nm spatial resolution through the precise fabrication of Au/TiO2/Pt sandwich nanostructures. In situ SERS study reveals that hydrogen species can efficiently spillover at Pt‐TiO2‐Au interfaces, and the ultimate spillover distance on TiO2 is about 50 nm. Combining kinetic isotope experiments and density functional theory calculations, it is found that the hydrogen spillover proceeds via the water‐assisted cleavage and formation of surface hydrogen–oxygen bond. More importantly, the selectivity in the hydrogenation of the nitro or isocyanide group is manipulated by controlling the hydrogen spillover. This work provides molecular insights to deepen the understanding of hydrogen activation and boosts the design of active and selective catalysts for hydrogenation. [ABSTRACT FROM AUTHOR]

Precise control and accurate understanding of the ordering degree of bimetallic nanocatalysts (BNs) are challenging yet crucial to acquire advanced materials for the oxygen reduction reaction (ORR). AuCu BNs with various ordering degrees were synthesized to evaluate the influence of ordering degree on the ORR at a molecular level using in situ Raman spectroscopy. The activity of AuCu BNs was improved by over 2 times after a disorder-to-order transition, making the performance of highly ordered AuCu BNs exceed that of benchmark Pt/C. Direct Raman spectroscopic evidence of key intermediate (*OH) demonstrates that the active site is the combination site of Au and Cu. Moreover, two distinct *OH species are observed on the ordered and disordered structure, and the ordered site is more beneficial for ORR due to its lower affinity to *OH. This work deepens the understanding on the important role of ordering degree on BNs and enables the design of improved catalysts., (© 2022 Wiley-VCH GmbH.)