Open Access Research Article Issue
Upconversion 32Nb2O5-10La2O3-16ZrO2 glass activated with Er3+/Yb3+ and dye sensitized solar cell application
Journal of Advanced Ceramics 2017, 6 (4): 312-319
Published: 19 December 2017
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Er3+/Yb3+ codoped niobium pentoxide glasses were fabricated by the aerodynamic levitation (ADL) method with rapid cooling rate. All samples with various doping concentrations showed good upconversion luminescence properties under 980 nm laser excitation. The structure, transmittance spectrum, and luminescence properties of the samples were systemically investigated by XRD, UV-Vis-NIR spectrophotometer, and upconversion spectra. All transparent samples exhibited green and red upconversion emissions centered at 532, 547, and 670 nm. Experimental results showed that the sample codoped with 1 mol% Er3+/Yb3+ has the strongest upconversion emissions, and the increase of the doped Yb3+ concentration results in the increased red emission and reduced green emission. The logI-logP plot of green emission indicated that the green emissions reach the saturation at high pump power excitation, deviating from the low-power regime. After one-photon energy transfer (ET) process, 4I11/2+4I11/24F7/2+4I15/2 process between the two neighboring Er3+ ions was responsible for the population of the 4S3/2/4H11/2 states. The niobium pentoxide codoped with Er3+/Yb3+ bulk glasses could be used in the dye sensitized solar cell (DSSC) to improve the efficiency.

Research Article Issue
Aerodynamic levitated laser annealing method to defective titanium dioxide with enhanced photocatalytic performance
Nano Research 2016, 9 (12): 3839-3847
Published: 10 September 2016
Abstract PDF (1.8 MB) Collect

Defective TiO2 has attracted increasing attention for use in photocatalytic and electrochemical materials because of its narrowed band-gap and improved visible-light photocatalytic activity. However, a facile and efficient approach for obtaining defect-rich TiO2 still remains a challenge. Herein, we demonstrate such an approach to narrow its bandgap and improve visible-light absorption through implanting abundant defects by aerodynamic levitated laser annealing (ALLA) treatment. Note that the ALLA method not only provides rapid annealing, solidifying and cooling process, but also exhibits high efficiency for homogeneous and defective TiO2 nanoparticles. The laser-annealed TiO2 achieves a high hydrogen evolution rate of 8.54 mmol·h–1·g–1, excellent decomposition properties within 60 min, and outstanding recyclability and stability, all of which are superior to the corresponding properties of commercial P25.

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