A novel polyvinylpyrrolidone (PVP)‐directed crystallization route is successfully developed for the shape‐selective synthesis of ZnO particles with distinctive shapes, including monolayer, bilayer, and multilayer structures, gears, capped pots, hemispheres, and bowls, at temperatures as low as 32 °C. This route is based on exploiting a new water/PVP/n‐pentanol system. In the system, PVP can greatly promote ZnO nucleation by binding water and direct ZnO growth by selectively capping the specific ZnO facets, which is confirmed by IR absorption spectra. The bandgap of the ZnO particles is readily tuned by modifying the product morphology by adjusting the PVP chain length, PVP amount, water volume, and reaction temperature. The remarkable ZnO structures and the biomimetic method demonstrated here not only expand the structures and applications of ZnO but also provide a new approach to explore the unusual structures for novel physicochemical properties and technological applications. Furthermore, the novel ZnO/Au/ZnO sandwich structure is successfully fabricated by inserting a Au plate into the bilayer ZnO structure.

The attachment of water molecules to poly(vinylpyrrolidone) (PVP) is used in conjunction with the region‐selective distribution of PVP and water in a water/PVP/n‐pentanol system to confine reactions along the surface of PVP, thus achieving the highly shape‐selective synthesis of anisotropic Au nanostructures with controlled sizes and remarkable shapes such as regular octahedrons, triangles, rods, dumbbells, belts, and hexagons. The IR absorption spectra of the Au nanoparticles confirm that the nanoparticles are formed around PVP, and corroborate the adsorption of PVP on Au. The size, shape, and plasmon resonance of the Au nanoparticles can be readily tuned by modifying the adsorption behavior and/or the reducing ability of PVP by adjusting the relative amounts of PVP and water, directly adding gold seeds, or changing the stirring conditions in the reaction mixture. The obtained highly pure anisotropic Au nanostructures and the synthesis method demonstrated here enable us to study distinct nanostructures to search for novel physicochemical properties and technological applications. Our method is also successfully extended to prepare highly pure silica spheres, tubes, and needles with controlled aspect ratios.

A novel water/polyvinylpyrrolidone (PVP)/n‐pentanol ternary system is successfully developed to realize the controlled growth and assembly of silver nanoprisms using a one‐step synthesis for the first time. The highly shape‐selective growth and assembly of nanoprisms is based on the unique water/PVP/n‐pentanol interface. It is seen that the cooperative assembly of nanoprisms with PVP greatly affects the size‐dependent nanoprism plasmon bands. The plasmon bands of the assemblies are closer to those of bulk silver than to those of nanoprisms. The method is simple and versatile, and is successfully extended to prepare Au and Pd nanoprisms, lamellar ZnO particles, and layered ZnO assemblies with high purity. The method may provide powerful technology for shape‐selective synthesis and assembly of lamellar nanoparticles with novel structures and functions in nanotechnology.

Novel Au-induced polyvinylpyrrolidone (PVP) aggregates with bound water (PVP-water) were created for the highly shape-selective synthesis of distinctive silica nanostructures, such as core-shell spheres, rods, snakes, tubes, capsules, thornlike, and dendritic morphologies. A water/PVP/n-pentanol system was first designed to bind water to PVP, and then Au nanoparticles were used to induce the PVP-water species to aggregate into distinctive soft structures by exploiting the interplay between PVP and gold. This was confirmed by the IR absorption spectra. The bound water in the soft structures was consumed during the hydrolysis of tetraethylorthosilicate and the target silica nanostructures were obtained. The soft structures, and therefore, the silica morphologies, can be readily tuned by adjusting the experimental parameters. The tunable Au-induced PVP-water soft structures reported herein open up new dimensions for the synthesis of distinctive nanomaterials (other than silica) that have new physicochemical properties and applications. These soft structures were also successfully extended to synthesize ZnO and SnO(2) particles with remarkable shapes, such as spheres, leaves, T-shaped structures, and dendritic morphologies.

High purity (∼88%) gold nanobelts have been synthesized in the water/polyvinylpyrrolidone (PVP)/n-pentanol system created to realize the selective-adsorption of PVP on Au which directs Au to grow in belt form via the one-dimensional (1D) self-assembly of triangular Au nanoplates. These nanobelts present uniform thickness and lateral dimension, large aspect ratio up to 160, unique 60° angle end structure, and double-peak plasmon resonance property. The PVP directed 1D self-assembly method demonstrated here may provide a general route for the shape-selective synthesis of the other 1D functional nanostructures.