Mingjian Yuan

A Multianalyte Chemosensor on a Single Molecule: Promising Structure for an Integrated Logic Gate

A novel fluorescent probe that possess both BODIPY and Rhodamine moieties has been designed for the selective detection of Hg(2+) and Ba(2+) ions on the controlling by a logic gate. The characteristic fluorescence of the Ba(2+)-selective OFF-ON and the Hg(2+)-selective fluorescence bathochromic shift can be observed, and the concept has been used to construct a combinational logic circuit at the molecular level. These results will be useful for further molecular design to mimic the function of the complex logic gates on controlling.

Light Harvesting and Efficient Energy Transfer in Dendritic Systems: New Strategy for Functionalized Near‐Infrared BF2‐Azadipyrromethenes

A series of dendritic systems, which are capable of funneling energy from the periphery to the core, have been synthesized. The photophysical properties of the dendrimers, generations 0-2, have been determined. The light-harvesting ability of these compounds increases with increasing generation arising from the increase in molar extinction coefficient. Selective excitation of the donor leads to an efficient energy transfer (>90 %) to the acceptor. The approach provides a facile synthesis for modification of near-infrared BF2-Azadipyrromethene.

Controlled growth and field emission properties of CuS nanowalls

Vertically oriented CuS nanowalls supported on a copper substrate have been synthesized through a facile method involving an inorganic vapour–solid phase reaction. The CuS nanowalls were well connected to form an extended network. The shapes of the CuS nanostructures could be controlled by adjusting the reaction conditions such as the reaction temperature and the flow rate of argon gas. The crystallinity of the nanowalls was investigated by XRD and their morphological features were characterized by FESEM. Both TEM and SAED analyses revealed that the nanowalls are single-crystalline. The field emission properties of the CuS nanowalls were investigated. The turn-on field and current density of the CuS nanowalls are comparable to those of many other semiconductor nanomaterials, which suggests that the CuS nanowalls may have potential applications in the vacuum microelectronics industry.

Organic−Inorganic Nanohybrids via Directly Grafting Gold Nanoparticles onto Conjugated Copolymers through the Diels−Alder Reaction

Nanocomposites of poly- p-phenyleneethynylene gold nanoparticles (PPE-Au) were synthesized via directly grafting maleimide functionalized gold nanoparticles (MA-Au) onto PPE chains by a mild Diels-Alder reaction. The Diels-Alder reaction between copolymers and MA-Au leads to self-assembly of the MA-Au as well as enhances electronic communication between the copolymers and inorganic particles. The as-prepared hybrid nanoassemblies show homogeneous status and well-defined interfaces, which facilitate the electronic interaction between conjugated polymers and gold nanoparticles. Moreover, dramatic photophysical properties and an influence on the assembly behavior of gold nanoparticles are also exhibited, which allows this procedure to be performed as a smart assay for monitoring the process of the Diels-Alder reaction.

Large Third-Order Optical Nonlinear Effects of Gold Nanoparticles with Unusual Fluorescence Enhancement

The third-order nonlinear optical properties of two solutions of gold nanoparticles protected by carbazolyldiacetylene derivatives were investigated using the Z-scan technique. Both gold nanoparticle colloid solutions in toluene show unusual fluorescent enhancement and large third-order nonlinear optical properties including nonlinear absorption and refractive effects. When extending the pi-conjugated length of the ligands, the third-order nonlinear properties of composite materials based on gold nanoparticles were enhanced accordingly.