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α-Fe2O3 particles were prepared by a solution-derived method with annealing at ∼800 °C. By particle transfer, the particles were applied to photoanodes for photoelectrochemical water splitting.

A semitransparent Ta3N5 photoanode is designed for efficient and durable solar water splitting. The Ta3N5-CuInSe2 tandem device exhibits an initial and stabilized solar-to-hydrogen efficiency of ∼9% (highest for metal oxides/nitrides) and 4%, respectively.

Tantalum nitride (Ta3N5) is a visible-light-responsive semiconductor that may be capable of achieving the 10% solar-to-hydrogen (STH) efficiency required to allow the commercialization of water splitting systems. However, despite immense research efforts, the highest STH efficiency yet reported for photoanodes based on Ta3N5-nanorods (NRs) is only 2.7%. Therefore, it is imperative to build a theoretical foundation that explains the various loss mechanisms and their correlations with structural and material properties, so as to optimize the performance of this material. The present work devised a detailed numerical model based on an in-depth analysis of the performance characteristics of photoanodes made from either Ba-doped or undoped Ta3N5-NRs. This experimentally calibrated optoelectrical modelling enabled predictions of various factors related to performance loss, including optical effects, charge carrier recombination and resistive loss. Certain physical parameters, such as charge carrier lifetime, diffusion length, hole extraction rate from the NR surfaces to the electrolyte and the series resistance of the photoanode, could also be calculated. The results show that the enhanced performance obtained with Ba doping can be primarily attributed to increases in the carrier lifetime and diffusion length. The present model was recalibrated using experimental data from the literature to examine hidden effects of the NRs’ dimensions on optical and recombination losses. On this basis, various design principles are presented herein that should allow the fabrication of efficient Ta3N5-NRs photoanodes for commercial STH production.

Heterostructure-based photoanodes have been investigated to enhance light absorption and promote the generation and extraction of charge carriers for efficient solar-to-hydrogen energy conversion. ...

The development of lithium-ion batteries (LIBs) with high-energy densities faces challenges to meet the ever-growing market demands. Tungsten oxide (WO3) with high theoretical capacity and low cost...

In the field of micro/nanofluidics, the channel open/close valves are among the most important technologies for switching and partitioning actions and integration of various operations into fluidic circuits. While several types of valves have been developed in microfluidics, few are capable in nanofluidics. In this study, we proposed a femtoliter (fL) volume nanochannel open/close valve fabricated in glass substrates. The valve consists of a shallow, circular and stepped-bottom valve chamber connected to nanochannels and an actuator. Even with tiny deformation occurring at the nanolevel in glass, an open/closed state of a nanochannel (10-1000 nm) can be achieved. We designed a fL-valve based on an analytical material deformation model, and developed a valve fabrication process. We then verified the open/closed state of the valve using a 308 fL-valve chamber with a four-stepped nanostructure fitting an arc-shape of deflected glass, confirmed its stability and durability over 50 open/close operations, and succeeded in stopping/flowing an aqueous solution at 209 fL s-1 under a 100 kPa pressure in a 900 nm nanochannel with a fast response of ∼0.65 s. A leak flow from the closed valve was sufficiently small even at a 490 kPa pressure-driven flow. Since the developed fL-valve can be applied to various nanofluidic devices made of glass and other rigid materials such as plastic, it is expected that this work will contribute significantly to the development of novel integrated micro/nanofluidics chemical systems for use in various applications, such as single cell/single molecule analysis.

Photocatalytic splitting of water under solar light has proved itself to be a promising approach toward the utilization of solar energy and the generation of environmentally friendly fuel in a form of hydrogen. In this work, we demonstrate highly efficient solar-to-hydrogen conversion efficiency of 7.7% by photovoltaic–photoelectrochemical (PV–PEC) device based on hybrid MAPbI3 perovskite PV cell and WO3/BiVO4 core–shell nanorods PEC cell tandem that utilizes spectral splitting approach. Although BiVO4 is characterized by intrinsically high recombination rate of photogenerated carriers, this is not an issue for WO3/BiVO4 core–shell nanorods, where highly conductive WO3 cores are combined with extremely thin absorber BiVO4 shell layer. Since the BiVO4 layer is thinner than the characteristic carrier diffusion length, the photogenerated charge carriers are separated at the WO3/BiVO4 heterojunction before their recombination. Also, such architecture provides sufficient optical thickness even for extremely thin BiVO4 layer due to efficient light trapping in the core–shell WO3/BiVO4 nanorods with high aspect ratio. We also demonstrate that the concept of fill factor can be used to compare I–V characteristics of different photoanodes regarding their optimization for PV/PEC tandem devices.

Among strategies of fuel production, photoelectrochemical water splitting for hydrogen generation is garnering significant attention. The challenge for solar energy harvesting is material development with intense photocatalytic activity, efficient free-charge generation, separation, and transport. Tantalum nitride (Ta3N5) and oxynitrides (Ta3NyOx) are recognized as promising candidates for this role. This research suggests a new route to engineer Ta3NyOx nanoparticles (NPs) with structure, crystallinity, chemical, and optoelectronic properties controlled by design. This work employs a single-step plasma-based technique that takes advantage of dc reactive magnetron sputtering of tantalum in Ar/N2 mixtures. The NPs with the chemical composition of Ta3N3.9O0.6 are synthesized; however, they become partially oxidized when exposed to air, providing an inwardly-directed gradient of the nitrogen concentration. The core-region consists of n-type sub-stoichiometric Ta3Ny with a band gap of

The next-generation cooling devices are gradually being scaled to smaller than the size of high-performance microchips to enable local heat removal from small hot spots. Realization of a micro/nanofluidic heat pipe device is a challenging task, as it requires high condensation efficiency in an ultra-small space and sufficient liquid transport without employing any wick. Herein, we demonstrate a two-phase loop micro heat pipe device based on unique liquid properties in extended nanospace (10–1000 nm) to meet the growing demands of the miniaturization of electronics and optoelectronics. The device, which contains a small volume of liquid (tens of nanoliter) and does not require a wick, can be conveniently embedded in the microchip. The capillary condensation of water on nanopillars was investigated. The experimental results showed a significant enhancement of the condensation rate on nanopillars for a faster vapor–liquid phase transition. In addition, a streaming potential measurement was performed to evaluate the liquid transport during operation of the micro heat pipe device. This method enables the measurement of water flow rates through extended nanochannels without requiring probe molecules. The micro heat pipe device was verified to work properly. Finally, the cooling performance of the micro heat pipe device was quantitatively estimated, and improvements were proposed to achieve highly efficient cooling.

Zinc telluride (ZnTe)-based photocathodes with appropriate modifications showed incident-photon-to-current conversion efficiencies (IPCEs) higher than 30% at 420–520 nm, reached 40% IPCE at 460 nm, and were not zero up to 710 nm because of photoexcitation related to the intermediate-band. ZnTe films were prepared by productive close-spaced sublimation. After surface modification with CdS and Pt, the photocathode showed clear cathodic photoresponse in the phosphate buffer solution. The modulation of substrate temperature, incorporation of Cu, and further surface modification with very thin Mo and Ti layers significantly enhanced cathodic photocurrent which contributes to hydrogen evolution from water. Through the measurement of IPCEs, photoelectrochemical hydrogen evolution from water utilizing photoexcitation related to the intermediate-band was first confirmed. The photocathode showed advantageous durability under simulated sunlight: during irradiation of about 50 min, the stabilized photocurrent slightly decreased from 1.6 mA cm−2 to 1.5 mA cm−2.

We have developed dry etching process of lithium niobate (LN) wafer using neutral loop discharge reactive ion etching (NLD-RIE) to fabricate both micro- and nano-channels for investigating proton diffusion enhancement in ferroelectric nanochannels. We have also developed low-temperature direct bonding process between LN wafers. Two-hundred parallel nanochannel array of 200-nm deep and wide and 400-μm long connected to two microchannels (width: 500 μm, depth: 5.9 μm) at the both ends were fabricated. We have succeeded in measuring the proton diffusion coefficient as high as 1.2×10−8 m2/s.

Single-cell analysis is of increasing importance in many fields, but is challenging due to the ultra-small volumes (picoliters) of single cells. Indeed, analysis of a specific analyte might require the analysis of a single molecule or several molecules. Analytical processes usually include sampling, chemical processing, and detection. Although several papers have reported chemical processing and detection methods for single cells, a sampling method compatible with maintaining the viability of a single cell during sampling has yet to be developed. Here, we propose a femtoliter sampling method from a living single cell using micro/nanofluidic device technology. The sampling of 39 fL of cytoplasm from a single human aortic endothelial cell was demonstrated and its viability after sampling was confirmed.

Autonomous micro/nano mechanical, chemical and biomedical sensors require persistent power sources scaled to their size. Realization of autonomous micro-power sources is a challenging task, as it requires combination of wireless energy supply, conversion, storage and delivery to the sensor. In this work, we realized solar light driven power source that consists of a micro fuel cell (μFC) and a photocatalytic micro fuel generator (μFG) integrated on a single microfluidic chip. The μFG produces hydrogen by photocatalytic water splitting under solar light. The hydrogen is then consumed by the μFC to generate electricity. Importantly, the byproduct water returns back to the photocatalytic μFG via recirculation loop without losses. Functionality of both devices relies on novel phenomena in extended-nano fluidic channels that ensure ultra-fast proton transport. As a proof of concept, we demonstrate that μFG/μFC source achieves remarkable energy density of ~17.2 mWh cm-2 at room temperature.

Nanostructured photoanodes based on well-separated and vertically oriented WO3 nanorods capped with extremely thin BiVO4 absorber layers are fabricated by the combination of Glancing Angle Deposition and normal physical sputtering techniques. The optimized WO3 -NRs/BiVO4 photoanode modified with Co-Pi oxygen evolution co-catalyst shows remarkably stable photocurrents of 3.2 and 5.1 mA/cm(2) at 1.23 V versus a reversible hydrogen electrode in a stable Na2 SO4 electrolyte under simulated solar light at the standard 1 Sun and concentrated 2 Suns illumination, respectively. The photocurrent enhancement is attributed to the faster charge separation in the electronically thin BiVO4 layer and significantly reduced charge recombination. The enhanced light trapping in the nanostructured WO3 -NRs/BiVO4 photoanode effectively increases the optical thickness of the BiVO4 layer and results in efficient absorption of the incident light.

The surface modification is indispensable to facilitate new functional applications of micro/nanofluidics devices. Among many modification techniques developed so far, the photo-induced chemical modification is the most versatile method in terms of robustness, process simplicity, and feasibility of chemical functionality. In particular, the method is useful for closed spaces, such as post-bonded devices. However, the limitation by optical diffraction limit is still a challenging issue in scaling down the pattern sizes to nanoscale. Here, we demonstrated a novel surface modification on sub-100 nm scale utilizing the novel optical near-field (ONF) generated on nanostructures of photocatalyst (TiO2). The minimum pattern size of 40 nm, which was much smaller than diffraction limit, was achieved using a visible light source (488 nm) and a conventional irradiation setup. The controllability of pattern size by light intensity, the feasibility of functionality, and the non-contact working mode have impacts on surface patterning of post-bonded micro/nanofluidics devices. It is also worthy to note that our results verified for the first time the ONF on nanostructures of non-metal materials and its ability to manipulate the chemical reaction on nanoscale.

TiO 2 films deposited on unheated substrates of alumina silicate glass by rf. (13.56 MHz) magnetron sputtering in the mixture of O 2 and Ar gases have been studied with X-ray diffraction (XRD), Atomic Force Microscopy (AFM) and optical spectroscopy. Structural and optical properties of TiO 2 films deposited at different O 2 concentrations and total pressures have been analyzed. Photocatalytic properties of TiO 2 films were characterized by following the degradation of methylene blue molecules under UV irradiation. It was found that the rate of methylene blue decomposition strongly depends on morphology and crystallinity of the deposited films, namely on the content of the anatase phase and on the size of the anatase grains. The best photocatalytic activity was found on TiO 2 films consisting of pure anatase phase with the size of grains of about 450 A. With the help of those films a thin film reactor for water purification has been designed and tested.

Pyrene and 1-pyrenebuturic acid molecules were deposited on glass and copper substrates with the formation of submicron dots by laser-induced molecular micro-jet implantation through polar and non-polar liquid layers. The size of the smallest 1-pyrenebuturic acid molecules dots prepared on a glass substrate by implantation through water and diiodomethane was estimated to be about 400 nm and 300 nm at laser fluences of 235 J/cm 2 and 326 J/cm 2 , respectively. The fluorescence and the Raman spectra showed that the implanted 1-pyrenebutyric acid molecules did not decompose during the implantation process. The smallest size of a pyrene dot was 700 nm at the laser fluence of 378 J/cm 2 . However, the pyrene dots could be formed only by implantation through a water layer.

Anodic oxidation of Ti nanorods prepared by glancing angle deposition has been used for the fabrication of brush-type nanostructures of TiO2. During the anodization process, small TiO2 nanotubes grew on the walls of Ti nanorods until all Ti was converted to the oxide. As a result we obtained highly porous material that consists of TiO2 nanotubes arranged in shells around central oxide cores, which replaced former Ti nanorods. The combination of glancing angle deposition and anodization techniques creates unique possibilities for the fabrication of TiO2 nanostructures with a hierarchical ordering.

Structural, optical and photocatalytic properties of various TiO2 nanostructures prepared by glancing angle deposition (GLAD) and by electrochemical anodic oxidation of Ti were studied. The TiO2 nanorods were prepared on unheated glass substrates by reactive sputtering of Ti in a mixture of Ar and O2 gases in a glancing angle deposition (GLAD) regime. The crystal structure of the TiO2 nanorods was characterized by X-ray diffraction (XRD) and the obtained spectra showed that both anatase and rutile phases are present in the GLAD deposited nanorods with the ratio which corresponds to the ratio of Ar and O2 in the working gas. In addition, TiO2 nanostructures were fabricated by electrochemical anodic oxidation of Ti films and Ti nanorods prepared by GLAD in the oxygen free atmosphere at 0.1 Pa of Ar.

Nanocomposite Ti/hydrocarbon plasma polymer (Ti/ppCH) films were deposited by DC magnetron sputtering of titanium target in n-hexane, argon, or a mixture of these two gases. The resultant films were heterogeneous, with inorganic regions of nanometer scale distributed within a plasma polymer matrix. The titanium content was controlled by adjusting the argon/n-hexane ratio in the working gas. In the pure n-hexane atmosphere, the Ti concentration was found to be below 1 at %, whereas in pure argon it reached 20 at %, as measured by Rutherford backscattering spectroscopy and elastic recoil detection analysis (RBS/ERDA). A high level of titanium oxidation is detected with TiO(2), substoichiometric titania, and titanium carbide, composing an inorganic phase of the composite films. In addition, high hydrogen content is detected in films rich with titanium. Ti-deficient and Ti-rich films proved equally good substrates for adhesion and growth of cultured human osteoblast-like MG 63 cells. In these cells, the population densities on days 1, 3, and 7 after seeding, spreading area on day 1, formation of talin-containing focal adhesion plaques as well as concentrations of talin and osteocalcin (per mg of protein) were comparable to the values obtained in cells on the reference cell culture materials, represented by microscopic glass coverslips or a polystyrene dish. An interesting finding was made when the Ti/ppCH films were seeded with calf pulmonary artery endothelial cells of the line CPAE. The cell population densities, the spreading area and also the concentration of von Willebrand factor, a marker of endothelial cell maturation, were significantly higher on Ti-rich than on Ti-deficient films. On Ti-rich films, these parameters were also higher or similar in comparison with the reference cell culture materials. Thus, both types of films could be used for coating bone implants, of which the Ti-rich film remains effective in enhancing the endothelialization of blood contacting artificial materials.

The effective one-step physical approach is demonstrated for the fabrication of anatase titanium dioxide nanotubes through r.f. magnetron sputtering of TiO 2 on a highly ordered nanoporous anodic alumina template. The nanostructured TiO 2 benefited from the combination of unique properties of both the sputtering technique that provided well-controlled environment for the fabrication of anatase phase TiO 2 and the porous anodic alumina (PAA) that provided uniform and ordered nanopores. The photocatalytic properties of TiO 2 films were characterized following the degradation of methylene blue molecules under UV light irradiation. The photocatalytic activity of the nanostructured TiO 2 films has been found to be approximately twice higher in comparison with the flat TiO 2 films fabricated at the same conditions.

Organic molecular dots were successfully produced by means of a nano second pulsed dye laser on glass and indium tin oxide (ITO) substrates, with sizes of several hundred nanometres. The method involves the transfer of organic molecules from the source Coumarin 6 (C6) and poly [2-methoxy, 5-(2′-ethyl-hexyloxy)-p-phenylene-venylene] (MEH-PPV) films onto a target material through a water filled space-gap using a laser induced molecular jet (LIMJ). In this way, the organic dots of Coumarin 6 and MEH-PPV molecules were successfully implanted onto the glass and ITO targets. The present results demonstrate the possibility to significantly improve photo electronic or photoelectric devices such as novel photonic crystal and molecular device sensors, and so on.

The transfer of a polymeric micropattern onto a poly(methyl methacrylate) film surface was achieved by the pulsed laser irradiation of Coumarin 6 molecules using self-organized polymer honeycomb templates. The molecular implanted areas were analyzed by fluorescence microscopy and fluorescence spectroscopy. It was found that the implantation patterns were affected by the configuration of the sample, the template, and the atmospheric conditions. This technique is applicable to the production of molecular patterns on a centimeter-scale region of polymer film surfaces by a simple process. [DOI: 10.1380/ejssnt.2008.222]

Implantation of organic molecules into conductive organic or inorganic materials on the nanometre scale is one of the challenging problems in materials research that has to be solved. We have developed an advanced method of laser implantation suitable for producing organic molecular dots with sizes of a few hundred nanometres on organic and inorganic solid materials. This method involves transferring of organic molecules from a source film to a target material through a water-filled space-gap using a laser-induced molecular micro-jet. In this way, organic dots of Coumarin 6 (C6) molecules were successfully implanted into different target materials such as polymer, glass, copper, indium tin oxide (ITO), stainless steel, and so on. The shapes of the implanted dots as well as the shapes of the holes, caused by damage to the source or target films during laser irradiation, depended on whether water or air filled the space-gap between the films.

Preparation procedure and properties of composite SiO x / hydrocarbon plasma polymer films are described and discussed. The composite films have been prepared by RF sputtering in argon from two balanced magnetrons equipped with silica (SiO2) and polyimide (PI) targets. The films obtained reveal a wide range of properties which depend on the preparation conditions; primarily on the RF power delivered to the magnetrons. Morphology and composition of the composite films have been analysed by means of AFM, TEM, RBS/ERDA and FTIR. Wettability in terms of contact angle of water increases from 28 ∘ to 46 ∘ when the content of the SiO x component of the composite increases. Peculiar properties of the composite SiO x / hydrocarbon plasma polymer films are discussed with respect to their elemental composition and nature of chemical bonds created on the surface of the films. Finally, an attempt is made to express the amount of inorganic phase present in the organic matrix in terms of a filling factor.

Efficient photocatalytic water splitting requires effective generation, separation and transfer of photo-induced charge carriers that can hardly be achieved simultaneously in a single material. Here we show that the effectiveness of each process can be separately maximized in a nanostructured heterojunction with extremely thin absorber layer. We demonstrate this concept on WO3/BiVO4+CoPi core-shell nanostructured photoanode that achieves near theoretical water splitting efficiency. BiVO4 is characterized by a high recombination rate of photogenerated carriers that have much shorter diffusion length than the thickness required for sufficient light absorption. This issue can be resolved by the combination of BiVO4 with more conductive WO3 nanorods in a form of core-shell heterojunction, where the BiVO4 absorber layer is thinner than the carrier diffusion length while it’s optical thickness is reestablished by light trapping in high aspect ratio nanostructures. Our photoanode demonstrates ultimate water splitting photocurrent of 6.72 mA cm−2 under 1 sun illumination at 1.23 VRHE that corresponds to ~90% of the theoretically possible value for BiVO4. We also demonstrate a self-biased operation of the photoanode in tandem with a double-junction GaAs/InGaAsP photovoltaic cell with stable water splitting photocurrent of 6.56 mA cm−2 that corresponds to the solar to hydrogen generation efficiency of 8.1%.

Efficient photocatalytic water splitting requires effective generation, separation and transfer of photo-induced charge carriers that can hardly be achieved simultaneously in a single material. Here we show that the effectiveness of each process can be separately maximized in a nanostructured heterojunction with extremely thin absorber layer. We demonstrate this concept on WO3/BiVO4+CoPi core-shell nanostructured photoanode that achieves near theoretical water splitting efficiency. BiVO4 is characterized by a high recombination rate of photogenerated carriers that have much shorter diffusion length than the thickness required for sufficient light absorption. This issue can be resolved by the combination of BiVO4 with more conductive WO3 nanorods in a form of core-shell heterojunction, where the BiVO4 absorber layer is thinner than the carrier diffusion length while it's optical thickness is reestablished by light trapping in high aspect ratio nanostructures. Our photoanode demonstrates ultimate water splitting photocurrent of 6.72 mA cm(-2) under 1 sun illumination at 1.23 V(RHE) that corresponds to ~90% of the theoretically possible value for BiVO4. We also demonstrate a self-biased operation of the photoanode in tandem with a double-junction GaAs/InGaAsP photovoltaic cell with stable water splitting photocurrent of 6.56 mA cm(-2) that corresponds to the solar to hydrogen generation efficiency of 8.1%.

Deposition of plasma polymer films by r.f. magnetron sputtering of polyimide in an atmosphere of argon, nitrogen and in a self-sputtering mode is studied. In situ analytical techniques are applied to monitor the composition of both plasma and growing film during the deposition. A co-evaporation regime is observed at higher applied powers. Such a regime is characterized by a significant increase in deposition rate of plasma polymer films. In addition CO-based groups appear in the plasma volume and in the resulting films. The films deposited in a pulsed mode are similar in composition to those deposited in the continuous regime at equivalent power. The plasma polymer films are found to be stable to short-term oxidation in air.

Coumarin 6 (C6) molecules were implanted into poly butyl methacrylate (PBMA) polymer films following excitation using a pulsed dye laser coupled with a microscope. The mechanism of this microscopic laser induced molecular implantation method (LIMIT) is discussed on the basis of experimental parameters affecting the implanted area's size. The C6 molecules were ejected from a C6 source film facing a PBMA target film with various interface distances between them. The area size variation was observed in terms of the density distribution of the ejected C6 molecules in the plume and the plume shape was estimated at different laser fluences. The size and the shape of the ejected C6 molecules are discussed in terms of the processes taking place in the plume. Based on the obtained results, the implantation method was optimized so that the formation of extended fine-art quality green-color fluorescent patterns consisting of C6 molecular dots could be demonstrated.

Perylene molecules have been successfully implanted onto borosilicate glass plates, forming fluorescent features of 420 nm in diameter, using a method involving laser induced molecular micro-jet ejection through a water layer. The technique utilises a polymer source film in which perylene molecules are dispersed, a borosilicate glass substrate as a target and a pulsed laser. The space gap between the source film and the target is filled with liquid water. Perylene molecules dispersed in the polymer source films are photo-excited using 4-ns laser pulses resulting in the ejection of the molecules from the source matrix after which they become implanted into the target after passing through the water layer. This new advanced implantation method, using a laser induced molecular micro-jet through water, gives fine spatial control for fixing functional organic molecules in a designated region on hard dielectric materials and will have application in the fabrication of molecular devices, molecular sensors, and opto-electronics.

Composite SiOx/hydrocarbon plasma polymer films have been prepared by RF sputtering of silica and hydrocarbon polymer (polyethylene (PE) or polypropylene (PP)) targets placed on two balanced magnetrons. The morphology and composition of the composite films have been analysed by means of AFM, RBS/ERDA, FTIR, and XPS. The obtained films demonstrated wide range of wettability and hardness in dependence on the preparation conditions. When the ratio of RF powers delivered to the individual targets P SiO 2 / P PE ( P PP ) changed from 0.1 to 10 the static contact angles of water varied from 75° to 25° and from 80° to 33° for composite films obtained from PE and PP, respectively. The hardness of the composite films varied from 2400 to 3400 N/mm2 and from 1600 to 2000 N/mm2 for the above-mentioned cases, respectively. Peculiar properties of the composite SiOx/hydrocarbon plasma polymer films have been discussed with respect to the elemental composition and nature of the chemical bonds established on the surface of the films.

Polyimide-like thin films were deposited by thermal degradation of polyimide with and without simultaneous activation by a glow discharge excited using an r.f. planar magnetron. The films deposited without discharge are similar in composition to conventional polyimide, whereas the deposition with plasma results in cross-linked coatings with composition typical for plasma polymers e.g. prepared by r.f. sputtering of polyimide. AFM reveals rough surface topography for the films evaporated without plasma. The application of plasma leads to very smooth plasma polymer films.

A microdot pattern of multiple organic molecules was prepared. Fluorescent molecules, which absorb visible light, were added to a commercial ultraviolet photopolymerization polymer solution and the polymer solution was polymerized by irradiating with nanosecond pulsed visible laser light. The size and the shape of the polymerized dots differed with the irradiation condition and the kind of the added molecules. Based on these results, a microdot pattern of multiple organic molecules was prepared by repeating a micropatterning process with the molecules.

Structural and mechanical properties of the TiN films deposited on stainless-steel substrates by rf. magnetron sputtering have been studied. The TiN films of few hundreds of nanometers in thickness were fabricated, varying both the total pressure of the N 2 /Ar reactive gas mixture and N 2 partial pressure in a chamber. It was found that the morphology of the TiN films strongly depended on the N 2 concentration of the working gas. A formation of the (2 0 0) phase was detected at 50% of N 2 concentration. The tribological properties of the deposited films strongly depended on the total pressure. A low frictional coefficient of 0.14 has been measured for TiN films deposited at 50% of N 2 , at a total pressure 9 Pa.

A simple method for silicon microfabrication has been successfully developed. Polypropylene (PP) film as a resist was prepared on a surface of silicon (Si) (1 0 0) plate by an rf magnetron sputtering method. A pulsed laser light was focused and irradiated to the PP film and a part of the film was removed by laser ablation process in the spot at certain laser intensity. When the sample was immersed in a potassium hydroxide solution, etching occurred only at the part that the PP film was removed by laser ablation. These results raise the possibility of this method as a process for Si microfabrication.

A pulsed dye laser was used to implant Coumarin 6 (C6) and tetraphenyl-porphine zinc functional organic molecules (ZnTPP) into poly (butyl methacrylate) (PBMA) polymer films. The resulting films were patterned with a matrix of well-formed dots several micrometers in diameter. The dependence of the size of implanted dots on the laser intensity has been studied at different concentrations of the dopants in the source films. The mass distribution of each particular dot on PBMA target film was inferred using the fluorescence intensity distribution of the implanted dots. The dependence of the lower and upper limits of the dot's size was determined when source films having different dopant concentrations were used. Based on the results obtained the optimum parameters for creation of extended “two colour” complex patterns consisting of both, C6 and ZnTPP, molecular dots were established.

Composite SiOx/PTFE films were deposited by rf sputtering in argon using balanced magnetron equipped with a PTFE/SiO2 target. The composition of deposited films, found by XPS and FTIR, ranged from fluorocarbon plasma polymers with very small SiOx content up to coatings with a greater incorporation of SiOx. The hardness of fluorocarbon polymer films with increased concentration of SiOx was 2400 N/mm2. This is between two to three times higher than in the case of fluorocarbon plasma polymers with very low SiOx content. The static contact angle of water ranges from 112 to 95° and the refractive index from 1.49 to 1.43, when incorporation of SiOx into fluorocarbon plasma polymer matrix decreases.

We demonstrate a new approach to plasmonic enhanced photocatalytic water splitting by developing a novel core-shell Ti@TiO2 brush nanostructure where an elongated Ti nanorod forms a plasmonic core that concentrates light inside of a nanotubular anodic TiO2 shell. Following the ubiquitous element approach aimed at providing an enhanced device functionality without the usage of noble or rare earth elements, we utilized only inexpensive Ti to create a complex Ti@TiO2 nanostructure with an enhanced UV and Vis photocatalytic activity that emerges from the interplay between the surface plasmon resonance in the Ti core, Vis light absorption in the Ti-rich oxide layer at the Ti/TiO2 interface and UV light absorption in the nanotubular TiO2 shell.

Engineering using liquids confined in channels 10-1000 nm in dimension, or "extended-nanofluidics," is the next target of microfluidic science. Liquid properties at this scale were unrevealed until recently because of the lack of fundamental technologies for investigating these ultrasmall spaces. In this article, the fundamental technologies are reviewed, and the emerging science and technology in the extended-nanospace are discussed.

Laser induced molecular implantation technique (LIMIT) has been used for site-controlled fabrication of pixel arrays of organic light-emitting diodes in a form of dots with a diameter of several micrometers. N,N'-Bis(3-methylphenyl)-N,N'-diphenylbenzidine (TPD) dots, which were implanted into the poly(3,4-ethylene dioxythiophene)–poly(styrene sulphonate) (PEDOT–PSS) layer, act as recombination centers between the hole- and electron-transport layers in the indium tin oxide (ITO)/PEDOT–PSS/TPDdots/tris(8-hydroxyquinoline) aluminum (Alq3)/Mg–Ag sandwich structure, and illuminate intense green light. We studied fluorescence spectra of the implanted TPD dots and the dependence of their size and morphology on the intensity of a laser pulse, as well as the electroluminescence resulted from the organic light-emitting device (OLED) arrays. The site-controlled fabrication of such small OLEDs opens up an opportunity for production of electroluminescent devices with ultrahigh resolution.

Integrated chemical systems on microfluidic chips are further downscaling to 101–103 nm scale, which we call extended-nano space. The extended-nano space is a transient space from single molecules to bulk condensed phase, and new liquid properties can be expected in fluidics and chemistry. Actually, many unique liquid properties are increasingly reported which are quite different with microspace. In addition, development of new chemical devices is in progress by utilizing the unique characteristics of extended nanospace. Although new research area is being formed, there exist many challenges in fundamental technologies (nanofabrication, fluidic control, detection, partial surface modification, etc.) due to the extremely small size. Optical near field (ONF) technology is one promising solution because the size of ONF is comparable with extended-nano space and also has unique optical properties such as non-adiabatic optical transitions. In this chapter, we introduce our approach to construct a new micro and extended-nano chemical systems by utilizing the unique characteristics of ONF.