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Reduced graphene oxide (RGO) coated with ZnO nanoparticles (NPs) was synthesized by a self-assembly and in situ photoreduction method, and then their application for removing organic pollutant from water was investigated. The RGO@ZnO composite nanomaterial has unique structural features including well-dispersed NPs on the surface and dense NPs loading. This composite exhibited a greatly improved Rhodamine B (RhB) adsorption capacity and an improved photocatalytic activity for degrading RhB compared to neat ZnO NPs. These properties made RGO@ZnO reusable for pollutant adsorbent. The composite showed an excellent cycling performance for organic pollutant removal up to 99% recovery over several cycles via simulated sunlight irradiation.

Shape conversions of silver nanoplates were realized by heating and subsequent light irradiation. The initial silver nanoprisms were transformed into silver nanodisks gradually in the process of heating, which was possibly achieved through dissolving and readsorption of silver atoms on the surface of silver nanoplates. Subsequently, under light irradiation, the heating induced silver nanodisks were reversed to silver nanoprisms in the same solution. The dissolved oxygen was found to play a pivotal role in the shape conversion from nanoprism to nanodisk. In addition to heating, deionized water could induce the shape conversion of silver nanoplates when it was added to precipitate of the initial silver nanoprisms after centrifugation. Citrate in solution is essential to the photoinduced shape conversion process. Transmission electron microscopy (TEM) and extinction spectroscopy results demonstrated that localized surface plasmon resonance (LSPR) properties of silver nanoplates were effectively tuned through shape conversion.

Anisotropic silver nanoparticles were coated on silk fibers to obtain colorful silk with good antibacterial properties. Different morphologies of silver nanoparticles gave different colors to the silk fibers, because of changes in the localized surface plasmon resonance of the nanoparticles. More efficiently, mixing of different silver nanoparticles in different proportions extended the range of colors. Unlike the conventional silk dyeing process, which is energy-intensive, the coloration process with silver nanoparticles was achieved at room temperature. The silk fibers displayed strong adsorption ability for silver nanoparticles during the coloration process. The modified silk fibers exhibited different bright colors as the silver nanoparticles on the surface of the fibers varied. Significantly, the silk fibers treated with silver nanoparticles showed significant antibacterial abilities against Escherichia coli. Moreover, good color fastness to washing was achieved through coating of polydimethylsiloxane on the surface of silk treated with silver nanoparticles.

We synthesized a surfactant-encapsulated polyoxoanion, (DODA)16As4W30Cu4O112‚114H2O (denoted SEC-1), which possesses a hydrophobic dimethyl dioctadecylammonium (DODA) shell and an encapsulated hydrophilic polyoxoanion core in organic phases. The novel organic/inorganic composite can form stable Langmuir monolayers, but it is significantly distorted when spread onto an air/water interface although the general core-shell structure seems to remain. Langmuir-Blodgett (LB) films of SEC-1 are readily prepared by transferring the monolayers onto substrates with a transfer ratio near 1. It has been proposed that there exist well-orientated alkyl chains and highly defined layer structure in LB films. Fourier transformation infrared spectroscopy at different temperatures indicates that two obvious phase transitions appear near 34 and 47 °C for multilayer LB films of SEC-1. The polyoxoanion can be organized to some extent within LB films with its long axis parallel to the substrate by comparing the IR transmission spectrum with the reflection-absorption spectrum. The one-monolayer LB film of SEC-1 possesses a homogeneous and flat surface morphology, and a water contact angle of 104 ( 3°for odd-layer LB films shows a highly hydrophobic surface.