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The LiGd(MoO 4) 2 :Eu3+ phosphors were successfully synthesized using the hydrothermal method followed by calcination. The effects of different dosages of the cationic surfactant dodecyl trimethyl ammonium bromide (abbreviated as DTAB) on the luminescent properties were discussed in detail. It was found that the luminescence intensity of the sample at the optimum DTAB addition was 3.03 times higher than that without DTAB under the 465 nm excitation peak. The change of the morphology was observed by SEM and TEM, which indicated that there were many cracks on the surface of the sample at the optimal DTAB additive contents. Moreover, the average particle size of the sample at the optimum DTAB dosage is larger than that of the sample without DTAB. The lifetime of the sample with the optimum DTAB addition shorter than that without DTAB, and then the fluorescence scintillation could be reduced. Furthermore, the crystal field environment of Eu3+ ions were analyzed by Judd-Ofelt theory. [ABSTRACT FROM AUTHOR]

Herein, we fabricated honeycomb ceramics with different porosities and pore shapes via the layer-by-layer deposition of cordierite (2MgO·2Al 2 O 3 ·5SiO 2) particle ink, obtaining proper rheological properties using a direct-writing technology. No collapses as well as minimal cracking and bending were observed in the internal structure of the samples after calcination. We measured and compared the internal porosity and specific surface area of honeycomb ceramics with the same pore shape but different pore dimensions, as well as the same pore dimension but different pore shapes. The samples were both loaded with an γ-Al 2 O 3 washcoat and Pd-based catalyst using the same method for the catalytic combustion of toluene. The different porosity and pore shape influenced the catalytic efficiency. This study may provide some useful guidelines for fabrication of honeycomb ceramics by direct writing technology, which could be used to remove volatile organic pollutants(VOCs). [ABSTRACT FROM AUTHOR]