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The existence of Pb which formed polyatomic ions such as PbCl+, PbAr+would interfere the determination of ultra-trace Am by ICP-MS. An extraction chromatography method for the removal of Pb interference was provided in this work to improve the determination accuracy of ultra-trace Am by ICP-MS. In this study, Sr resin was applied to separate Am and Pb because of the great difference between Am and Pb on adsorption ability. The variable parameters including nitric acid concentration, loading volume, column height and loading amount were investigated to optimize the separation conditions for high recovery of Am (R(Am)) as well as high decontamination factor of Pb (DF(Pb)). The optimal separation method was recommended in the study with the recovery of Am over 99% and the decontamination factor of Pb over 2 × 105. Moreover, the method was successfully applied to the analysis of 241Am in the simulated samples.

Vertically aligned rutile TiO2nanowire arrays (NWAs) with lengths of ∼44 μm have been successfully synthesized on transparent, conductive fluorine-doped tin oxide (FTO) glass by a facile one-step solvothermal method. The length and wire-to-wire distance of NWAs can be controlled by adjusting the ethanol content in the reaction solution. By employing optimized rutile TiO2NWAs for dye-sensitized solar cells (DSCs), a remarkable power conversion efficiency (PCE) of 8.9% is achieved. Moreover, in combination with a light-scattering layer, the performance of a rutile TiO2NWAs based DSC can be further enhanced, reaching an impressive PCE of 9.6%, which is the highest efficiency for rutile TiO2NWA based DSCs so far.

A novel self-powered UV photodetector (UVPD) based on the photoelectrochemical cell (PECC) has been constructed using the TiO2coated SnO2mesoporous spheres (SnO2-MS@TiO2). This self-powered UVPD displays a higher photocurrent density compared to the UVPD with the pure SnO2-MS. By means of external quantum efficiency (EQE), UV-vis absorption, and electrochemical impedance measurements, we scrutinize the intrinsic role of the TiO2coating layer on the photocurrent enhancement. Under UV irradiation, this UVPD exhibits a high on/off ratio of 11519, a fast rise time of 0.007 s and decay time of 0.006 s, together with the excellent visible-blind characteristic and linear optical signal response. The self-powered photodetector is a promising candidate for application in high-sensitivity and high-speed UVPDs.

The effect of air and oxygen annealing on the structural and the optical properties of hydrothermally synthesized ZnO nanorods was investigated. After hydrothermal synthesis, the resulting ZnO nanorods were annealed in air and under an oxygen atmosphere at 370°C for 1 h. X-ray diffraction results revealed that the oxygen-annealed nanorods possessed high crystallinity with a hexagonal-wurtzite crystal structure in the (002) plane. Evaluation of strain showed a tensile lattice strain of 0.426% resulting from oxygen annealing. The photoluminescence measurements showed that the relative intensity ratio of the near-band-edge emission (NBE) to the green emission (INBE/IGE) increased from ~2.6 for the as-grown ZnO nanorods to ~68.7 when the nanorods were annealed under oxygen. After annealing, a red shift of ~30 and ~44 meV in the NBE was observed for the nanorods that were annealed in air and under oxygen, respectively. This shift is attributed to the interaction between the neutral acceptors and the adsorbed oxygen atoms.

The effect of indium cluster on enhanced ultraviolet luminescence in AlxInyGa1–x–yN quaternary alloys with increasing Al composition was investigated. X-ray diffraction (XRD), temperature-dependent photoluminescence (PL), transmittance spectra, and Raman scattering measurements have been employed to study the AlxInyGa1–x–yN quaternary alloy. Abnormal S-shaped temperature dependence of PL emissions in high Al content sample originated from carrier localization induced by indium nanoclusters, which is in good agreement with the pure InN mode measured by Raman scattering. A large Stokes shift between the emission peak and the absorption edge is also found in the high Al content sample. All these observations suggested that the enhancement of carrier localization by indium nanoclusters is responsible for the increase in radiative recombination probability with increasing Al composition. Our results demonstrated that AlxInyGa1–x–yN quaternary alloy can exhibit a larger band gap than that of GaN and enhanced ultraviolet luminescence due to the existence of indium nanoclusters. Meanwhile, the effect of indium clusters was increased with Al compositions increasing, even at low indium mole fraction about 4%.

We present a time-saving staining protocol based upon the low-toxicity and nonvolatile solvent dimethyl sulfoxide for a high-efficiency dye-sensitized solar cell, which is very critical for the roll-to-roll flexible cell production. Power conversion efficiencies of 11.7−12.1% were achieved under AM1.5G simulated sunlights. The intrinsic roles of lithium cations on efficiency enhancement were scrutinized by measuring transient absorption and electrical impedance spectroscopies. Our studies have revealed that lithium ions can enhance exciton dissociation at the energy-offset dye/titania interface effectively. Charge collection is not found to be a crucial current loss channel in our high-efficiency dye-sensitized solar cell.

We report a heteroleptic ruthenium complex (C107) featuring the electron-rich 5-octyl-2,2′-bis(3,4-ethylenedioxythiophene) moiety conjugated with 2,2′-bipyridine and exhibiting 10.7% power conversion efficiency measured at the AM1.5G conditions, thanks to the enhanced light-harvesting that is closely related to photocurrent. This C107sensitizer has an extremely high molar extinction coefficient of 27.4 × 103M−1cm−1at 559 nm in comparison to its analogue C103(20.5 × 103M−1cm−1at 550 nm) or Z907(12.2 × 103M−1cm−1at 521 nm) with the corresponding 5-hexyl-3,4-ethylenedioxythiophene- or nonyl-substituted bipyridyl unit. The augmentation of molar extinction coefficients and the bathochromic shift of low-energy absorption peaks along with the π-conjugation extension are detailed by TD-DFT calculations. The absorptivity of mesoporous titania films grafted with Z907, C103, or C107sublinearly increases with the molar extinction coefficient of sensitizers, which is consistent with the finding derived from the surface coverage measurements that the packing density of those sensitizers decreases with the geometric enlargement of ancillary ligands. When the dye-coated titania film is immersed in a high-efficiency redox electrolyte, a lower density molecule grafting on titania nanocrystals leads to more deep electronic states and a faster charge recombination at the titania/dye/electrolyte interface at a given electron Fermi level, explaining the observation of a larger dark current and a lower open-circuit photovoltage. Electrical impedance analysis further reveals that the electron diffusion length in nanocrystalline titania films is shortened along with the π-conjugation extension of ancillary ligands.

Large-scale uniform bicone-like ZnO microcrystals were successfully synthesized via a simple solution method at lower temperature (80 °C). The as-prepared bicones, composed of two cones, possess a single-crystal hexagonal structure and grow along the [0001] direction. The influence of the reactant concentration on the size and shape of the ZnO samples has been studied in detail, and the results revealed that reactant concentration plays a crucial role in determining the final morphologies of the samples. The growth process of the bicone-like ZnO microcrystals was viewed by field emission scanning electron microscopy (FESEM) characterization, and a possible formation mechanism was proposed. Optical properties of the bicone-like ZnO microcrystals were also investigated by photoluminescence (PL) spectroscopy. The room-temperature PL spectrum of the bicone-like ZnO microcrystals shows a strong UV emission peak. The UV emission is further identified to originate from the radiative free exciton recombination by temperature-dependent PL. In addition, the bicone-like ZnO microcrystals exhibit excellent sensing properties toward ethanol gas at an operating temperature of 300 °C. The response and recovery times are 2 and 3 s, respectively. These results indicate that the bicone-like ZnO microcrystals have potential applications in fabricating optoelectronic devices and gas sensors.

Large-scale uniform nutlike ZnO microcrystals are successfully synthesized via a facile hydrothermal process. Field emission scanning electron microscopy and transmission electron microscopy results reveal that the as-prepared ZnO products have average lengths of 2.2 μm and diameters of 1.8 μm, possessing a wurtzite structure. The evolution process of the nutlike ZnO microcrystals has been viewed by FESEM characterization, and the results reveal that the reaction time plays a crucial role in determining the final size and shape of the samples. It is also found that the existence of triethanolamine (TEA) is vital to the formation of the complex microcrystals formed from self-assembled nanoparticles, and a possible formation mechanism is proposed. Optical properties of the ZnO sample are also investigated by PL spectroscopy. It is found that the intensity of the visible emission shows an obvious decrease after the nutlike ZnO is annealed in air for 90 min. Moreover, the UV emission is further identified to originate from the recombination of the radiative free exciton and the donor bound excition by the temperature-dependent PL spectra.

We conjugated 2-(hexylthio)thiophene with bipyridine to construct a new heteroleptic polypyridyl ruthenium sensitizer exhibiting a charge-transfer band at 550 nm with a molar extinction coefficient of 18.7 × 103M−1cm−1. In contrast to its analogues Z907 and C101, a mesoporous titania film stained with this new sensitizer featured a short light absorption length, allowing for the use of a thin photoactive layer for efficient light-harvesting and conversion of solar energy to electricity. With a preliminary testing, we have reached 11.4% overall power conversion efficiency measured at the air mass 1.5 global conditions. Transient photoelectrical decays and electrical impedance spectra were analyzed to picture the intrinsic physics of temperature-dependent photovoltage and photocurrent.

Large-scale ZnO nanotube bundles were successfully synthesized by a single solution method at lower temperature. Every ZnO nanotube bundle is composed of closely packed nanotubes, with inner diameters of ∼350 nm and wall thicknesses of ∼60 nm, and forms radiating structures. The influence of the reaction time on the size and shapes of the ZnO samples was studied in detail, and the results revealed that the reaction time plays an important role in determining final morphologies of the samples. The formation of the tubular structure may be due to the selective dissolution of the metastable Zn-rich (0001) polar surfaces, and a possible growth model was proposed. Optical properties of the ZnO nanotube bundles were also investigated by photoluminescence (PL) spectroscopy. It was found that the UV emission peak of the nanotube bundles did not change its position, while the visible emission band showed an obvious red shift when the nanotube bundles were annealed in ambient oxygen. Moreover, the UV emission was further identified to originate from the radiative free exciton recombination by the temperature-dependent PL.

Solid-state electrolytes play a crucial role in the improvements of safety and electrochemical stability in all-solid-state lithium batteries (ASSLBs). In this review, we present the recent research and development of the composite solid polymer electrolytes for ASSLBs.