Sanqing Huang

Chromatic polydiacetylene with novel sensitivity.

Conjugated polymers have been investigated for a number of applications in optoelectronics and sensing due to their important electronic and optical properties. For instance, polydiacetylene (PDA) may change color in response to external stimuli and has been extensively explored as a material for chromatic sensors. However, the practical applications of PDA materials have been largely hampered by their irreversible chromatic transitions under limited stimuli such as temperature, pH, and chemical. As a result, much effort has been paid to improve the chromatic reversibility and increase the scope of external stimuli for PDA. In this tutorial review, the recent development of PDA materials which show reversible chromatic transition and respond to new stimuli including light and electrical current has been described.

A New and General Fabrication of an Aligned Carbon Nanotube/Polymer Film for Electrode Applications

High-temperature or vacuum processes are typically required to fabricate them, resulting in high costs. These electrode materials have been also shown to be unstable in many conditions, e.g., platinum may be dissolved in corrosive electrolytes and indium tin oxide is fragile and not resistant to acid. [ 4–6 ] In addition, there are limited sources for either platinum or indium. These disadvantages have largely hindered their practical applications in a wide variety of fi elds. Therefore, it is highly desired to develop new electrode materials with good stability, high effi ciency, and low cost. Recently, increasing interest has been paid to carbon nanotube (CNT)/poly mer composite fi lms, which may represent a family of promising electrode materials to simultaneously solve the above challenges due to incorporated excellent properties from CNTs and polymers. CNTs exhibit high mechanical strength and electrical conductivity, while polymers provide good fl exibility, high transparency, easy processing, and low cost. [ 7 , 8 ] CNT/polymer fi lms have been typically fabricated by dispersing two moieties in solvent, followed by spin coating or other solution processes. [ 9 ] Although it is easy to operate with relatively high effi ciency, random dispersion of CNTs in polymer matrices greatly decreases the physical properties of resulting composite fi lms. [ 10 ] For instance, electrical conductivities of CNT/polymer fi lms at room temperature are often less than 10 − 3 S cm − 1 , which largely reduces their electrode applications. In order to improve their electrical conductivities, aligned CNT/polymer fi lms by using CNT sheets as templates have been recently realized, and conductivities up to 10 2 S cm − 1

A novel fabrication of a well distributed and aligned carbon nanotube film electrode for dye-sensitized solar cells†

Carbon nanotubes (CNTs) have been recently fabricated into macroscopic films to improve their practical applications in a wide variety of fields, e.g. electrode materials. In the current CNT electrodes however, CNTs are typically interconnected to form networks or are aligned as lots of bundles, and the resulting photovoltaic devices based on the CNT electrodes have typically shown low energy conversion efficiencies. Here we report a new and general drying approach to make a well distributed and aligned CNT film which exhibits a rapid charge separation and transport. As a demonstration, it has been used as a counter electrode to fabricate dye-sensitized solar cells with an energy conversion efficiency of 9.05%.

UV-induced chromatism of polydiacetylenic assemblies.

Highly ordered lamellar polydiacetylene nanocomposites are synthesized by assembling polydiacetylene and azobenzene through a ready solution process. The trans-to-cis transition of azobenzene under UV light induces a conformational change of polydiacetylene with a color change from blue to red.

Stimuli-sensitive assemblies of homopolymers.

Two homopolymers assemble into nanoparitcles in a common solvent of water through ionic complexation. These nanoparticles reversibly and rapidly respond to both pH and temperature, and are particularly promising as intelligent systems.

Functional nanomaterials for optoelectric conversion and energy storage

1 Institute of Mathematics and Physics, Central South University of Forestry and Technology, Changsha, Hunan 410004, China 2 Shanghai Engineering Research Center of Aquatic-Product Processing & Preservation, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China 3 School of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China 4Department of Macromolecular Science and Engineering, Case Western Reserve University, Cleveland, OH 44106, USA 5Department of Chemical Engineering, New Mexico State University, Las Cruces, NM 88003, USA

Perpendicularly aligned carbon nanotube/olefin composite films for the preparation of graphene nanomaterials

There remains a common and critical challenge in the preparation of carbon nanotube (CNT) composite materials, i.e., random dispersion of CNTs in the second phase. Here we have reported a general method to prepare perpendicularly aligned CNT/olefin composite films through a conventional slicing technique. The thickness of a composite film can be accurately controlled from about fifty nanometers to fifty micrometers, and the diameter and density of CNTs may be varied in a wide range as required. In particular, due to the generated defect at the end during the slicing process, the separated CNTs from the composite film have been easily unzipped to produce graphenes in the forms of nanoribbons and nanosheets with a yield of almost 100% under ultrasonic treatment.

Functional nanomaterials for optoelectric conversion and energy storage 2014

1College of Science, Central South University of Forestry and Technology, Changsha, Hunan 410004, China 2Shanghai Engineering Research Center of Aquatic-Product Processing & Preservation, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China 3School of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China 4Department of Macromolecular Science and Engineering, Case Western Reserve University, Cleveland, OH 44106, USA 5Department of Chemical Engineering, New Mexico State University, Las Cruces, NM 88003, USA