Ultraviolet (UV)-ozone photo-annealing was applied to fabricate low-temperature high-performance solution-processed thin-film transistors (TFTs). With UV-ozone treatment at the optimal temperature of 300 °C, TFT devices showed an improved field-effect mobility of 1.73 cm2 V−1 s−1, a subthreshold slope (S) of 0.32 V dec−1, an on/off-current ratio greater than 1.3 × 107, and good operational bias-stress stability compared to those of InGaZnO TFT devices fabricated with only a conventional thermal-annealing process. The results of X-ray photoelectron spectroscopy and the maximum density of the surface states (Ns) confirm that the device improvement originates from reduced oxygen-related defects and improved electron trapping due to UV-ozone irradiation.

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Color‐tunable Ca4‐1.5xTa2O9: xTb3+ phosphors are prepared via a convenient solid‐state reaction and the cross‐relaxation mechanism is investigated. The concentration of Tb3+ ions greatly affects blue‐green emission in Ca4Ta2O9 samples. The cross‐relaxation effect is explained with the use of Raman and emission spectra and the thermal stability of Ca4‐1.5xTa2O9: xTb3+ is evaluated under excitation at 254 nm. Using the theoretical fitting results, the cross‐relaxation between Tb3+ ions, via energy transfer from 5D3 to 5D4, was determined to be a multipolar interaction of the dipole–dipole mechanism. The critical distance was calculated to be 15.45 Å. The thermal quenching temperature (T50) is higher than 200°C. Results show that Ca4‐1.5xTa2O9: xTb3+ phosphors have good thermal stability and color tunability.

The b-type vibration–rotation band of N2⋅SO2 near the SO2 ν3 band origin was observed in a molecular-beam, diode laser direct absorption experiment. Rotational transitions and Stark effect data for this complex were additionally measured using molecular-beam electric resonance methods. The vibrational band origin was 1361.1440(2) cm−1, shifted by 0.9167(2) cm−1 from that of the SO2 monomer. Rotational constants were measured for the upper and lower vibrational states with A″=8875.3(22) MHz, B″=1620.3(22) MHz, C″=1426.1(24) MHz, A′=8832.4(26) MHz, B′=1617.3(28) MHz, and C′=1431.6(15) MHz. The electric dipole moment components were determined, with μa = 0.0441(16) D and μc = 1.5884(29) D. The c component of the nitrogen quadrupole coupling component was found to be eqccQ = 1.30(21) MHz. A structure analysis gave the separation between the centers of mass of the monomers as 3.8925(28) Å. The angles between the symmetry axes of the SO2 and N2 units and the line connecting these monomers were calculated as 61.35° and 24.54°, respectively. Additionally, the SO2 monomer a axis was found to lie along the b axis of the complex. The electric dipole moment data indicate that the equilibrium angle for the SO2 is much closer to 90° than the rms result. These structural results were compared to model calculations of the binding energy of the complex.

Trace detection of common pesticide residue is necessary to assure safety of fruit and vegetables, given that the potential health risk to consumers is attributed to the contamination of the sources. A simple, rapid and effective means of finding the residue is however required for household purposes. In recent years, the technique in association with surface-enhanced Raman scattering (SERS) has been well developed in particular for trace detection of target molecules. Herein, gold nanoparticles (Au NPs) were integrated with sol-gel spin-coated Zirconia nanofibers (ZrO2 NFs) as a chemically stable substrate and used for SERS application. The morphologies of Au NPs/ZrO2 NFs were adjusted by the precursor concentrations (_X, X = 0.05–0.5 M) and the effect of SERS on Au NPs/ZrO2 NFs_X was evaluated by different Raman laser wavelengths using rhodamine 6G as the probe molecule at low concentrations. The target pesticides, phosmet (P1), carbaryl (C1), permethrin (P2) and cypermethrin (C2) were thereafter tested and analyzed. Au NPs/ZrO2 NFs_0.3 exhibited an enhancement factor of 2.1 × 107, which could detect P1, C1, P2 and C2 at the concentrations down to 10−8, 10−7, 10−7 and 10−6 M, respectively. High selectivity to the organophosphates was also found. As the pesticides were dip-coated on an apple and then measured on the diluted juice containing sliced apple peels, the characteristic peaks of each pesticide could be clearly identified. It is thus promising to use NPs/ZrO2 NFs_0.3 as a novel SERS-active substrate for trace detection of pesticide residue upon, for example, fruits or vegetables.