Diarylethenes for Memories and Switches

http://sces.phys.utk.edu/mostcited/mc1_1114.pdf

Colossal Magnetoresistant Materials: The Key Role of Phase Separation

Recent startling interest for lanthanide luminescence is stimulated by the continuously expanding need for luminescent materials meeting the stringent requirements of telecommunication, lighting, electroluminescent devices, (bio-)analytical sensors and bio-imaging set-ups. This critical review describes the latest developments in (i) the sensitization of near-infrared luminescence, (ii) “soft” luminescent materials (liquid crystals, ionic liquids, ionogels), (iii) electroluminescent materials for organic light emitting diodes, with emphasis on white light generation, and (iv) applications in luminescent bio-sensing and bio-imaging based on time-resolved detection and multiphoton excitation (500 references).

/pdf/lanthanide-luminescence-for-functional-materials-and-bio-1w9cppwf8r.pdf

Lanthanide luminescence for functional materials and bio-sciences

The semiconductor industry has seen a remarkable miniaturization trend, driven by many scientific and technological innovations. But if this trend is to continue, and provide ever faster and cheaper computers, the size of microelectronic circuit components will soon need to reach the scale of atoms or molecules—a goal that will require conceptually new device structures. The idea that a few molecules, or even a single molecule, could be embedded between electrodes and perform the basic functions of digital electronics—rectification, amplification and storage—was first put forward in the mid-1970s. The concept is now realized for individual components, but the economic fabrication of complete circuits at the molecular level remains challenging because of the difficulty of connecting molecules to one another. A possible solution to this problem is ‘mono-molecular’ electronics, in which a single molecule will integrate the elementary functions and interconnections required for computation.

Electronics using hybrid-molecular and mono-molecular devices

Organic solar cell research has developed during the past 30 years, but especially in the last decade it has attracted scientific and economic interest triggered by a rapid increase in power conversion efficiencies. This was achieved by the introduction of new materials, improved materials engineering, and more sophisticated device structures. Today, solar power conversion efficiencies in excess of 3% have been accomplished with several device concepts. Though efficiencies of these thin-film organicdevices have not yet reached those of their inorganic counterparts (η ≈ 10–20%); the perspective of cheap production (employing, e.g., roll-to-roll processes) drives the development of organic photovoltaic devices further in a dynamic way. The two competitive production techniques used today are either wet solution processing or dry thermal evaporation of the organic constituents. The field of organic solar cells profited well from the development of light-emitting diodes based on similar technologies, which have entered the market recently. We review here the current status of the field of organic solar cells and discuss different production technologies as well as study the important parameters to improve their performance.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0884291400094498

Organic solar cells: An overview

Photoinduced charge separation in multilayered heterostructures of conducting polymers and their doping effects

The C60/poly(isothianaphthene) (PITN) heterojunction device was fabricated and its electrical characteristics and photoirradiation effects were investigated. This device has current-rectifying function. Upon photoirradiation, both forward and backward currents were enhanced, and photovoltaic effects was also appeared. These results were discussed in terms of charge transfer between C60 and PITN in the ground state and photoexcited state.

Effects of C/sub 60/ on conducting polymer with small band gap

Multilayered heterostructures composed of negatively and positively charged conducting polymers have been fabricated by the self-assembly method, and their optical properties and photoconduction have been studied. Remarkable quenching of photoluminescence and enhanced photoconduction are found in the multilayered heterostructure. These phenomena are explained in terms of the efficient photoinduced charge separation at the heterointerfaces between the negatively and positively charged conducting polymers which are thought to act as photodonor and photoacceptor, respectively.

Photoinduced Charge Separation and Photocurrent in Multilayered Conducting Polymer Heterostructure by Self-Assembly Method

Persistent photoconductivity (PPC) has been observed in C60-doped poly(3-alkylthiophene) (PAT). PPC increases with increasing irradiation time, tending toward saturation. PPC also increases with C60 concentration, tending toward saturation or even decrease at high concentration. Novel temperature dependence of PPC has been observed. This PPC has been discussed in terms of enhanced photoexcited carrier density in C60 doped PAT and the suppression of the recombination of primary negative and positive carriers due to the stabilization of trapped electrons in C60 and defect states in PAT.

Persistent Photoconductivity in C60-Doped Poly(3-alkylthiophene)

Gold nanoparticles capped with a simplified ionic liquid-like ligand were prepared, which were incorporated into the fusion materials with ionic liquids at concentrations of up to 40 wt% of inorganic content. The fusion material of gold nanoparticles with an ionic liquid monomer was readily converted into a polymeric composite, in which gold nanoparticles showed high thermal stability.

/pdf/preparation-of-fusion-materials-based-on-ionic-liquids-and-2695vbd8ez.pdf

Tsuyoshi Kawai

Papers

Photoinduced charge separation in multilayered heterostructures of conducting polymers and their doping effects

Effects of C/sub 60/ on conducting polymer with small band gap

Photoinduced Charge Separation and Photocurrent in Multilayered Conducting Polymer Heterostructure by Self-Assembly Method

Persistent Photoconductivity in C60-Doped Poly(3-alkylthiophene)

Preparation of fusion materials based on ionic liquids and cationic gold nanoparticles