•PZT film was fabricated at 450 °C by introducing thermal UV/O3 treatment..•The obtained electrical characteristics of low-temperature processed PZT film were comparable with conventional processed ones..•The actuator using low-temperature processed PZT film was demonstrated.•Dependence of displacements change on the applied voltage was very consistent with that of the simulation.We report on the fabrication of a low-temperature sol-gel derived lead zirconium titanate (PZT) film and actuator, achieved by introducing a thermal ultraviolet/ozone (UV/O3) treatment. A spin-coated PZT gel film was irradiated with UV light on a heated stage (200 °C) in ambient O3, before crystallization. The thermal UV/O3 treatment created a reducing environment inside the PZT gel film, which inhibited the formation of the pyrochlore phase, leading to the direct formation of the perovskite phase after annealing at 450 °C. The low-temperature processed PZT film exhibited a preferential (111) orientation. The remanent polarization, coercive field, and leakage current of the PZT film obrained using this fabrication technique, were 23.6 μC/cm2, 109.6 kV/cm, and 10−6 A/cm2, respectively. We also fabricated an actuator using the low-temperature processed PZT film. The maximum displacement was approximately 130 nm at 10 V, which was close to the prediction of the simulation results. The proposed process shows great promise for the integration of PZT films with other systems.

•SPE column was successfully integrated on LEP chip.•A flow control technique to reduce sample volume for LEP technique was proposed.•The integrated chip can detect Pb at 10 ppb.Liquid electrode plasma – Atomic emission spectrometry (LEP-AES) is a novel elemental analysis method where a liquid sample is filled in a micro channel that has a narrow part at the center. High voltage is applied to the solution at the both ends of the channel, and consequently microplasma is generated in the channel. The microplasma is an excitation source for atomic emission spectrometry. The method is suitable for heavy metal detection. In this work, to improve detection limit, we integrated a solid phase extraction (SPE) column on a liquid electrode plasma chip (LEP chip) to improve the sensitivity of this method for lead (Pb) detection. The chip design and flow control technique was proposed based on the point of reducing the necessary eluent for one measurement. Chip pattern was made by Polydimethylsiloxane (PDMS) employing negative photolithography. The integrated chip was successful in detecting 10 ppb Pb in solution. Detection limit for Pb of LEP method is improved.Graphical abstract

This paper describes a quantitative measurement of trace elements (Na, Li) in high purity zirconium dioxide powder using liquid electrode plasma optical emission spectrometry (LEP-OES). Conventionally, for such type of measurements, inductively coupled plasma optical emission spectrometry (ICP-OES) is frequently employed. The detection limits of elements in zirconium by ICP-OES are degraded due to the spectra interference between the trace elements and zirconium of the matrix, because zirconium is a line rich element in spectra obtained by ICP-OES. LEP-OES is an elemental analysis method developed by the authors. The measurement principle is simple, as follows. Sample solution is put into a narrow channel on a small cuvette and voltage pulse is applied from both ends of the channel. At the center of the channel which is made narrower, the voltage and current are concentrated there, and plasma is generated. From the emission of the plasma, the quantitative analysis of the elements in the solution is achieved. The LEP-OES has the property that the emission of zirconium is relatively weak, so that highly sensitive measurement of trace elements in zirconium matrix can be conducted without interference. Sample solution is prepared by dissolving high purity zirconium dioxide powder and trace amounts of Na or Li with sulfuric acid. The voltage dependence and the pulse width dependence of optical emission spectra are also investigated. With increase of the voltage or the pulse width, the ratio of emission intensities of Na to those of hydrogen increases. This suggests that the ratio of sensitivity of two elements is variable, that means the element selectivity is controllable to some extent by the measurement conditions in LEP-OES. In the case of Na and H, the ratio can be controlled from 7.4 to 21.6%. Finally, the detection limits (3S.D.) of the trace elements, Na and Li, in 4000 μg g−1 zirconium dioxide aqueous solution are found to be 0.02 and 0.133 μg g−1, respectively. These values correspond to 5 μg g−1 for Na, 33.25 μg g−1 for Li in original high purity zirconium dioxide powder. The correlation coefficient of calibration curve was 0.995 for Na, 0.985 for Li. Those are comparable to the literature values of detection limits using ICP-OES.