The existence of lattice strain between two different materials can be used to control the fine structural configuration in a hybrid colloidal nanostructure. Enabled by such, the relative position change of Au and CdX in Au-CdX from a symmetric to an asymmetric configuration is demonstrated, which can further lead to fine tuning of plasmon-exciton coupling and different hydrogen photocatalytic performance. These results provide new insight into plasmon enhanced photocatalytic mechanisms and provide potential catalysts for photoreduction reactions.

Rigid three-dimensional (3D) Ni3S4 nanosheet frames assembled from ultrathin nanosheets are synthesized via a facile solvothermal method.

We report a topotactic reaction strategy to achieve the oriented attachment (OA) of colloidal metal chalcogenide quantum dots into micrometer-sized nanosheets and nanobelts (up to 6-7 μm) on both mechanically rigid and flexible substrates. The nonstoichiometric composition, crystallization and Ag doping were controlled. The strong surface adsorption of cations and thiol ligands facilitated micrometer-scale three-dimensional OA. The cations induced the formation of electrostatic forces, cation passivation on the nanosheet surface and overlap packing of the nanosheets, enabling good contact with the substrates and improved electron transport without severe obstruction of organic insulating barriers. The observation of weak anti-localization phenomena and Hall effect sensitivity (up to 188%) of non-stoichiometric Ag 2-δ Te nanosheet films as well as the improved I-V and photoresponse properties of Ag-doped CdX nanosheet films confirm efficient electron transport. The stable I-V properties of these nanosheet films on flexible substrates, even under bending forces, testify to their potential in flexible device applications.

This paper reports a strategy to get self-assembly of CuTe nanorods into hierarchical superstructures: the side-by-side self-assembly of nanorods into microscale one-dimensional (1D) nanowires (primary structure), the side-by-side alignments of the 1D nanowires into two-dimensional (2D) nanowire bundles (secondary structure), and the further rolling up of the 2D bundles into three-dimensional (3D) microtubes (tertiary structure). It was found that the oleylamine (OLA)/n-dodecanethiol (DDT) mixture as a binary capping agent was key to produce CuTe nanorods in the quantum size regime with high monodispersity, and this was a prerequisite for their hierarchical self-assembly based on elaborate control of the solvent evaporation process. The obtained CuTe microtube superstructures were used as SERS substrate and showed much stronger SERS enhancement than the as-prepared CuTe nanorods before assembly. This was probably ascribed to the remarkably enhanced local electromagnetic field arising from the plasmon coupling of CuTe nanorods in the well-assembled superstructures.