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Graphical abstract Metallic nanoparticles (NPs), as an efficient substrate for surface-enhanced Raman scattering (SERS), attract much interests because of their various shapes and sizes. The appropriate size and morphology of metallic NPs are critical to serve as the substrate for achieving an efficient SERS. Pulsed laser deposition (PLD) is one of the feasible physical methods employed to synthesize metallic NPs with controllable sizes and surface characteristics. It has been recognized to be a successful tool for the deposition of SERS substrates due to its good controllability and high reproducibility in the manufacture of metallic NPs. This review provides an overview about the recent advances for the preparation of SERS substrates by PLD technique. The influences of parameters on the sizes and morphologies of metallic NPs during the deposition processes in PLD technique including laser output parameters, gas medium, liquid medium, substrate temperature, and properties of 3D substrate are presented. The applications of SERS substrates produced by PLD in the environmental monitoring and biomedical analysis are summarized. This knowledge could serve as a guideline for the researchers in exploring further applications of PLD technique in the production of SERS substrate.

A variety of the modified X zeolites were used to catalyse the oxidative dehydrogenation of ethylbenzene to styrene with CO2 for the first time.

Acid-base bifunctional organic polymeric catalysts were synthesized with tunable structures. we demonstrated two synthesis approaches for structural fine-tune. In the first case, the framework flexibility was tuned by changing the ratio of rigid blocks to flexible blocks within the polymer framework. In the second case, we precisely adjusted the acid-base distance by distributing basic monomers to be adjacent to acidic monomers, and by changing the chain length of acidic monomers. In a standard test reaction for the aldol condensation of 4-nitrobenzaldehyde with acetone, the catalysts showed good reusability upon recycling and maintained relatively high conversion percentage.

The design of efficient catalysts with abundant active sites is fascinating but still is a great challenge for hydrogen evolution reaction (HER). Herein, a highly active Co-N-C hybrid array on nickel foam (Co-NCNT/NF) was constructed to enhance the HER activity. The 3D hydroxide nanosheets were utilized as a template and reactant to form the ordered ZIF-8 array by a solid-liquid interfacial release of Zn ions and coordination reaction, and the growth of ZIF-67 on the surface of ZIF-8 arrays assures the introduction of cobalt species into the precursor, catalyzing the formation of active Co-N-C sites. Based on the structure analysis and density functional theory calculations, an optimal configuration of the cobalt (111) face coated by carbon layer with one Co atom coordination to one N and C reveals a multi-site nature of the designed Co-NCNT/NF catalyst, which provided the improved conductivity, 3D hierarchical structure, the uniform distribution and efficient exposure of active Co-N-C sites. A small overpotential of 157 mV at a current density of -10 mA cm− 2 for HER in 1 M KOH was obtained, proving that the optimized proton adsorption on the multi-sites structure promotes the HER activity of Co-NCNT/NF.