1:30pm - 2:00pmInvited
Looking for New Synergies in Molecular Plasmonics by Hybrid Functional Nanostructures
Leibniz-Institut für Polymerforschung Dresden e. V, Germany
For the next generation of optical devices, the possibility of cost-efficient manufacturing requires both tailored control of the nanoparticle building blocks as well as an up-scaleable self-assembly method for macroscopic areas. We address these demands using bottom-up directed self-assembly of plasmonic nanoparticles to achieve collective plasmonic resonances in high quality plasmonic modes.[Nano Lett. 2014, 14, 6863.] A first step toward these tailored modes are the controlled synthesis of the plasmonic building blocks with specific mintage materials (gold or silver), subwavelength dimensions and morphologies with less symmetry axis (cubic shape). For instance, we have recently been able to fabricate core shell nanoparticles with a specific dielectric spacer for controlled electric field enhancement.[J. Phys. Chem. C 2015, 119, 9513, Nano Lett. 2017, submitted] As a second step, we use a directed self-assembly technique to align these building blocks to achieve collective plasmonic excitations such as constructive interference between plasmonic and diffraction modes (Fano resonance). Finally, we go one step further and use our directed self-assembly approach to discuss a magnetic metasurface. This magnetic mode could be excited using a plasmonic film coupled nanoparticle system.[Faraday Discuss., 2016, 191, 159.] This extraordinary electric field enhancement opens up new possibilities in ultra-sensitive sensing applications, plasmon-induced charge separations and the tailored control of the electric as well as magnetic field is important for super-absorber and metamaterial applications.
2:00pm - 2:30pmInvited
Metal-Purine Complexes for Material Applications
Indian Institute of Technology Kanpur, India
We will describe design strategies for modified adenine nucleobase derivatives to construct metal-mediated discrete complexes, ring-expanded purine skeletons, shape-selective MOFs, and purine-capped nanoparticles, with wide-ranging applications. Such strategies rely on rich chemistry of purine and pyrimidine derivatives, versatile coordination behavior, ability to bind a host of metal ions, which could be further tuned by the introduction of additional functionalities, and their inherent propensity to hydrogen bond and exhibit pi-pi interactions. Selected applications in the realm of material and biological applications will be presented.
2:30pm - 3:00pmInvited
Functional Bistable Rotaxanes: Synthesis, Function and Controllable Self-Assembly
East China University of Science and Technology, China
Mechanically interlocked molecules (MIMs), especially pseudorotaxanes and rotaxanes have attracted much attention for their appealing structures, potential applications in molecular switches and unique capabilities of mimicking biological behaviors in recent decades. In this presentation, we demonstrated recent advances on the synthesis, function and controllable self-assembly of rotaxane and pseudorotaxane based molecular switches. Firstly, a facile one-pot strategy for the preparation of a series of complicated [n]rotaxanes with highly structural complexity was demonstrated, and several rotaxanes can function as multi-level molecular machines that can perform both rotational motion and translational motion in response to external stimuli. Then, based on this synthetic methodology, we extended the molecular design and introduced some functional units into the molecular shuttles to realize multiple functions within single-molecule platforms. We developed a convenient way to characterize or monitor the mechanical motion of molecular machines by means of the fluorescent changes with different wavelengths or intensity that can be distinguished by naked eyes. The self-assembly of rotaxane-base molecular machine units, such as the grafting the molecular machines into the nanoparticles and polymers, was discussed. In addition, we also proposed a new strategy to prepare stimuli-responsive supramolecular polymers and to realize the controllable multicomponent self-assembly through reversible supramolecular interactions. Moreover, the controlled assembly and disassembly of this system were accompanied by switchable photocatalytic activity, which showed potential application as a novel smart and recyclable photocatalyst.[7,8]
 D.-H. Qu, Q.-C. Wang, Q.-W. Zhang, X. Ma, H. Tian, Chem. Rev. 2015, 115, 7543.
 X. Fu, Q. Zhang, S.-J. Rao, D.-H. Qu, H. Tian, Chem. Sci. 2016, 7, 1696.
 D.-H. Qu, B. L. Feringa, Angew. Chem. Int. Ed. 2010, 49, 1107.
 H. Zhang, J. Hu, D.-H. Qu, Org. Lett. 2012, 14, 2334.
 Z.-Q. Cao, Q. Miao, Q. Zhang, H. Li, D.-H. Qu, H. Tian, Chem. Commun. 2015, 51, 4973.
 Q.-W. Zhang, D.-H. Qu, J.-C. Wu, X. Ma, Q.-C. Wang, H. Tian, Langmuir, 2013, 29, 5345.
 Q. Zhang, D.-H. Qu, Q.-C. Wang, H. Tian, Angew. Chem. Int. Ed. 2015, 54, 15789.
 Q. Zhang, W.-Z. Wang, J.-J. Yu, D.-H. Qu, H. Tian, Adv. Mater. 2017, 29, 1604948.
3:00pm - 3:15pmOral
Synthesis and Upconversion Fluorescence Property of Sodium 3,3'-((2-(3-carboxypropyl)-1,3-dioxo-2,3,4,5,14,15-hexahydro-1H-dinaphtho[2,1-e:1',2'-g]isoindole-7,12-diyl)bis(oxy))bis(propane-1-sulfonate)
National Metal and Materials Technology Center, Thailand
Sodium 3,3'-((2-(3-carboxypropyl)-1,3-dioxo-2,3,4,5,14,15-hexahydro-1H- dinaphtho [2,1-e:1',2'-g]isoindole-7,12-diyl)bis(oxy))bis(propane-1-sulfonate) (M510) was synthesized by O-alkylation reaction to give the product as a yellow solid. The structure of M510 was characterized by 1H-NMR, 13C-NMR, FT-IR and HRMS. Optical properties of M510 were studied by UV-visible spectroscopy and fluorescence spectroscopy. The UV absorption of a dilute solution of M510 in H2O showed peaks at 270, 302, 377 and 423 nm and energy band gap of 2.05 eV. Normally, with this low energy band gap, M510 should emit light at wavelength beyond 600 nm but a dilute solution of M510 in water showed peaks at 497 nm and 611 nm when excited at 365 nm. In addition, M510 showed peak at 500 nm when excited at 580 nm which is the upconversion luminescence (UCL) phenomenon. Furthermore, not only can the upconversion of M510 be observed in H2O but also in other solvents such as DMSO and ethanol.
3:15pm - 3:30pmOral
White Quantum Dot Layer as Fast Color Converter for Visible Light Communication
1Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), Singapore; 2National University of Singapore, Singapore
There has been increasing interest in using light emitting diodes for communications besides illumination. Visible light communication (VLC) can help relieve the congested traffic and overcome cyber-security issues faced by Wi-Fi communications. Due to its fast modulation speed and low energy consumption, LEDs are the preferred choice for VLC. Currently, white light is generated by exciting yellow phosphors with blue InGaN light emitting diodes (LED). However, phosphors have a slow decay lifetime of ~60 ns, which limits the switching speed of white LED to a few MHz. This ultimately limits the rate of data transmission.
It has been proposed that white LED formed by coating various derivatives of photoluminescence polymers such as poly(pheylene vinylene) over a blue GaN LED, can produce white light with fast modulation speeds of 200 MHz. However, the theoretical quantum yield of PPV based devices is limited to 25% and colour control is poor since organic polymer has a broadband emission. Moreover, they suffer from degradation by light, oxygen and water.
Here, we demonstrate a high speed white light LED formed by using CdSe quantum dots (QDs) layer as fast color converter. CdSe QDs have high quantum yield and stability, making them desirable for optoelectronics applications. We have used exciton-plasmon coupling to further enhance the rate of decay, resulting in an overall carrier lifetime of ~2 ns. This is ~30× faster than commercial phosphor in white LEDs. Electrical modulation shows that such color converter can significantly increase the modulation bandwidth of white LEDs. Such plasmonic enhanced QD-LED is a promising candidate for high speed and high brightness white light communications.