A transmission surface plasmon resonance image (TSPRi) obtained with a plasmonic grating structure was investigated in combination with a smartphone camera. A substrate of a gold-coated CYTOP grating/glass slide showed the TSPR excitation wavelength of 675 nm at the incident light angle of 30°. The TSPRi acquired from a smartphone camera assembled with liquid crystal tunable filters corresponded with spectroscopic results. The sensitivity of this technique was 282/RIU. Due to changes in the sensitivity of the TSPRi intensity to the refractive index of the environment, this technique can be further developed for portable devices for sensor applications.

Detection of chlorpyrifos (CPF) using a surface plasmon resonance (SPR)-enhanced photoelectrochemical sensing system is demonstrated in this study. The presence of CPF was detected based on an increase in the short-circuit photocurrent when a sample is injected into the electrolyte at different concentrations. The short-circuit photocurrent signal was enhanced by both localized SPR of the gold nanoparticles and by the effects of grating-coupled propagating SPR. Using the hybrid SPR-enhancement system, CPF detection was achieved at concentrations as low as 7.5 nM. The proposed technique of leveraging a multifunctional photovoltaic effect can be used for a variety of sensing applications.

A novel and fundamental method was reported to judge states of lithium ion batteries (LIBs) using the capacitance and the voltage of the cells that were estimated from the real-time currents and voltage characteristics of the cells. We measured the differential capacitance, that is, dQ/dV or delta Q/ delta V that is equal to the currents (I) divided by differential voltages (dV/dt) calculated from the current and the voltage characteristics of the cell during the charging/ discharging, where Q is the charge that flows through the cell, V is the voltage of the cell and t is time. It is thought that the capacitance decrease with the degradation of the cell because the effective area of the electrodes is decreasing due to formation of undesirable compounds. The differential capacitance in some specific voltage range for the LIBs was approximately directly proportional to the state of the degradation of the cell. Therefore, it is concluded that the novel method is very useful to judge the state of the LIBs.

We have reported recently a novel method for cross-linking conjugated polymers involving a “precursor polymer” route, where the electrochemical method can be used to prepare ultrathin films on conducting metal and metal oxide surfaces. In this paper, we present the design, synthesis, protocol, and recent results in the application of these thin film materials. An emphasis will be given on how these films are characterized in-situ by a combined surface plasmon spectroscopy (SPS) and electrochemical approach. As a methodology, the concept can be extended to new methods of electrodeposition, patterning, and grafting of conjugated polymers on electrochemically addressable metal surfaces. Compared to spin-cast or electropolymerized monomer films, they are very robust both thermally and mechanically. Other applications of these films to sensors, dielectric materials, non-lithographic patterning, etc. are currently being investigated.

In this report, we describe the photo-induced in-plane alignment of nematic liquid crystal (LC) molecules, 5CB, in a hybrid cell with alternate self-assembled films of low-molecular weight azobenzene dye and polyelectrolyte on gold electrodes using the attenuated total reflection (ATR) measurement method. The molecular self-assembly process was also investigated by the ATR method. Reflectivities due to excitations of the surface plasmon polariton (SPP) were observed in the ATR properties of the LC cell. In-plane switching of the LC molecules adjacent to the aligning layer was evaluated from the ATR curves after irradiation of linearly polarized visible light to the LC cell. The sensitivity of the ATR method gives information on the alignment, tilt angle, and extent of LC reorientation in the bulk. Thus, the importance of using the molecular self-assembly processes of individual polyion-dye pairs for fabrication of new photo-aligning layers is emphasized.

Epitaxially grown films of Bi4Ti3O12 (BIT) were prepared on the substrate of a sapphire single crystal heated at 650°C using a sintered Bi4Ti3O12 target by electron cyclotron resonance (ECR) plasma sputtering. The BIT film of the same composition with the target was obtained under the conditions of microwave power(Mp) higher than 500 W and RF power(Rp) between 300 to 700 W. Increasing Mp or Rp, the deposition rate of the film was increased and the surface of the film became rough. The film exhibiting flat surface, good crystalline orientation and stoichiometric composition was prepared at such the high rate as 3.5 Å/sec under the conditions of Mp=500W and Rp=500W. Dielectric constants(1KHz) of the films deposited on (1120), (1102) and (0001) of sapphire were 93, 121 and 90, respectively, and refractive indexes of each films for the wave length of 632 nm were 2.32, 2.38 and 2.37, respectively.