Construction of superstructures with controllable morphologies from NPs is of great scientific and technological importance. A one-step method for simultaneous synthesis and assembly of Ag NPs to three-dimensional (3D) nanoporous superstructures is demonstrated. By varying the adsorption time of Ag precursors, an array of well-defined Ag superstructures with different morphologies are harvested. A "hot spot"-rich substrate for surface-enhanced Raman spectroscopy is established, which exhibits high sensitivity in trace detection of molecules. It is believed that the presented 3D nanoporous Ag superstructures hold great potential for various uses, such as novel multifunctional sensing and monitoring chips or devices.

Development of high performances gas sensors to monitor and detect the volatile organic compound triethylamine is of paramount importance for health and environmental protection. The Co3O4-ZnO nanoparticles composite was successfully synthesized by the one-step hydrothermal route and annealing process in this work. The gas sensitivity test results show that the composite exhibits excellent triethylamine-sensing performance at a cobalt content of 1 at%, indicating potential application for triethylamine detection. The sensor based on the Co3O4-ZnO composite had higher sensitivity to triethylamine, better selectivity, and faster response recovery rate compared with pure ZnO sensor. Combined with the structural characteristics of the characterized Co3O4-ZnO nanocomposite, the optimized triethylamine sensing performances can be ascribed to the p-n heterojunction effect between Co3O4 and ZnO, as well as the catalytic and high oxygen adsorption properties of Co3O4.

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Pressure-sensitive phenoxy-imine titanium catalyst (FI-catalyst) was successfully synthesized by covalently immobilizing it on the surface of functionalized polystyrene (PS) nanoparticles, which acted as a support and a giant ligand simultaneously. The supported catalyst shows high catalytic activities in ethylene polymerization. Utilizing this catalyst, a serious of unimodal polyethylenes with tailored molecular weights ranging from 2 000 000 to 300 000 were produced under various reaction pressures and temperatures. Particularly, when the polymerization pressure was shifted during the reaction, the ethylene polymer with bimodal molecular weight distribution was successfully synthesized in only a single reactor. Differential scanning calorimetry analysis of the resultant polyethylene revealed a large difference between crystallinities at the first and second heating cycles, indicating that the synthesized polyethylene is of low entanglement.

A facile method to prepare the nonspherical amphiphilic random copolymer of poly(styrene-co-methacrylic acid) (poly(St-co-PMAA)) latex particles with well-defined shapes and high yields by one-step batch emulsifier-free polymerization was demonstrated. In our strategy, only varying the molar ratio of styrene (St) to methacrylic acid (MAA), no seed-particles, no cross-linker, and no multistep control procedures were needed. Due to the presence of carboxyl groups on the surface of (poly(St-co-PMAA) latex particles, these latex particles can be used as templates for fabricating core-shell nonspherical functional materials, such as poly(St-co-PMAA)@SiO2 and poly(St-co-PMAA)@polypyrrole). The corresponding nonspherical hollow structures (SiO2 and polypyrrole) could be obtained after removal of the templates. In addition, poly(St-co-PMAA) latex particles exhibit interesting morphologies in ethanol.