Bohua Wu

Functionalization of Carbon Nanotubes by an Ionic‐Liquid Polymer: Dispersion of Pt and PtRu Nanoparticles on Carbon Nanotubes and Their Electrocatalytic Oxidation of Methanol

Small beginnings: Metal nanoparticle/CNT nanohybrids are synthesized from carbon nanotubes (CNTs) functionalized with an ionic-liquid polymer. The Pt and PtRu nanoparticles with narrow size distribution (average diameter: (1.3+/-0.4) nm for PtRu, (1.9+/-0.5) nm for Pt) are dispersed uniformly on the CNTs (see images) and show good performance in methanol electrooxidation.

Polymerized ionic liquid-wrapped carbon nanotubes: The promising composites for direct electrochemistry and biosensing of redox protein

Polymerized ionic liquid-wrapped carbon nanotubes (PIL-CNTs) were firstly designed for direct electrochemistry and biosensing of redox proteins. The CNTs were coated successfully with polymerized ionic liquid (PIL) layer, as verified by transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy. The PIL-CNTs were dispersed better in water and showed superior electrocatalysis toward O(2) and H(2)O(2) comparing to pristine CNTs and the mixture of IL monomer and CNTs. With glucose oxidase (GOD) as a protein model, the direct electrochemistry of the redox protein was investigated on the PIL-CNTs modified glassy carbon (GC) electrode and excellent direct electrochemical performance of GOD molecules was observed. The proposed biosensor (GOD/PIL-CNTs/GC electrode) displayed good analytical performance for glucose with linear response up to 6mM, response sensitivity of 0.853 microA mM(-1), good stability and selectivity.

Carbonization of ionic liquid polymer-functionalized carbon nanotubes for high dispersion of PtRu nanoparticles and their electrocatalytic oxidation of methanol

Based on the carbonization of ionic liquid polymer-functionalized carbon nanotubes (CNTs), surface-nitrogen-enriched CNTs (SNE-CNTs) were developed as a support for noble metal nanoparticles (NPs). Due to the high surface content and uniform distribution of the element nitrogen on the CNT surface, PtRu NPs were deposited uniformly on the surface of the SNE-CNTs with a small particle size and show superb performance for methanol electrooxidation.

Chitosan-functionalized carbon nanotubes as support for the high dispersion of PtRu nanoparticles and their electrocatalytic oxidation of methanol.

Carbon nanotubes (CNTs) were non-covalently functionalized with chitosan (Chit) and then employed as the support for PtRu nanoparticles. The functionalization was carried out at room temperature without the use of corrosive acids, thereby preserving the integrity and the electronic conductivity of the CNTs. Transmission electron microscopy reveals that PtRu nanoparticles were highly dispersed on the surface of Chit-functionalized CNTs (CNT-Chit) with small particle-size. Cyclic voltammetry studies indicated that the PtRu nanoparticle/CNT-Chit nanohybrids have a higher electrochemical surface area, electrocatalytic performance, and stability towards methanol oxidation compared to PtRu nanoparticles supported on the pristine CNTs.

Modulating the Electrochromic Performances of Transmissive and Reflective Devices Using N,N-Dimethyl Formamide Modified Poly(3,4-Ethylenedioxythiophene)/Poly(Styrene Sulfonate) Blend as Active Layers

As one of the important factors which affect the properties and applications of conducting polymers, the electrical conductivity of a poly(3,4-ethylenedoxy-thiophene)/ poly(styrene sulfonate) (PEDOT: PSS) blend was adjusted by using various amount of an organic solvent (N,N-dimethyl formamide, DMF) as an additive. The conductivities of PEDOT: PSS thin films can be increased dramatically, from 1.0 S to 32.1 S cm−1, with a 2/1 volume ratio of PEDOT: PSS/DMF loading after totally removing the organic solvent by annealing the film at 80° for 48 h in a vacuum oven. The optical contrasts of transmissive and reflective devices assembled using DMF-modified PEDOT: PSS as active layers exhibited a close relationship with the conductivity of PEDOT: PSS. Interestingly, high conductivity of PEDOT: PSS enhanced the contrast of a transmissive device, while high conductivity of PEDOT: PSS decreased the contrasts of a reflective device. The underlying reason is related to the different electrochromic mechanisms of these two types of device configurations.

Electrochromic Behaviors of Water-Soluble Polyaniline with Covalently Bonded Acetyl Ferrocene

A novel ferrocene-containing hybrid electrochromic material was synthesized via copolymerization of aniline with p-phenylenediamine functionalized acetyl ferrocene in the presence of poly (styrene sulfonate) dopant in an aqueous medium, and neat polyaniline (PANI) was prepared for comparison. The polymerization characteristics and the structure of the copolymer were systematically studied by Fourier-transform infrared, meanwhile, their electrochromic properties and electrochemical behaviors were tested by UV–vis spectra, cyclic voltammetry and electrochemical impedance spectroscopy (EIS). It was found that the strong covalent bond and large conjugated system between PANI and ferrocene enhance the electron transfer rate and electron delocalization in the ferrocene-polyaniline (Fc-PANI) hybrid. In particular, the electrochromic device with Fc-PANI as the active layer shows significant enhancement in optical contrast over the PANI-based device.