Publications by authors named "Weiguang Ran"

The photocatalytic conversion of carbon dioxide (CO) into "liquid sunshine" methanol (CHOH) using semiconductor catalysts has garnered significant attention. Increasing the number of effective electrons and regulating reaction pathways is the key to improving the activity and selectivity of CHOH. Due to the electron transport properties of semiconductor heterojunctions and reduced graphene oxide (rGO), a CoS/CoS-rGO nanocomposite was constructed and applied to the photocatalytic reduction of CO to CHOH.

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Photocatalytic CO reduction is considered as a promising strategy for CO utilization and producing renewable energy, however, it remains challenge in the improvement of photocatalytic performance for wide-band-gap photocatalyst with controllable product selectivity. Herein, the sulfur-doped In(OH) (In(OH)S-z) nanocubes are developed for selective photocatalytic reduction of CO to CH under simulated light irradiation. The CH yield of the optimal In(OH)S-1.

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To settle the unsatisfying efficiency and insufficient light harvesting ability of photocatalysts, we report on the development of Er/Yb-codoped BiOBr (BiOBr:Er/Yb) microparticles that were synthesized by a rational high-temperature solid-state reaction method. The prepared microcrystals exhibit high visible upconversion (UC) emissions with maximum intensities at = 0.01 when excited by a 980 nm laser.

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In this paper, Er/Yb co-doped CdMoO phosphors were prepared by a traditional high temperature solid state reaction method. Based on the 3D network structure of the CdMoO host and the efficient Er/Yb upconversion luminescence combinations, excellent green emission properties were observed when the prepared sample is irradiated with a laser at about 980 nm. For optical temperature sensors based on the fluorescence intensity ratio (FIR), the prepared phosphors have excellent sensitivity to temperature in the range of 293 to 473 K.

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Open-framework structured materials such as Prussian blue analogues and sodium superionic conductor (NASICON) materials have been regarded as promising electrode candidates for aqueous batteries. These materials exhibit outstanding long cycle stability and high rate capacity retention, due to their high ion diffusive rate in the crystal and the stable structure maintenance in the electrochemical reaction process. Herein, an open-framework structured material [Ni(en)][Fe(CN)] (NienHCF) is prepared and first used as a cathode material for aqueous sodium- and potassium-ion batteries.

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Through a solid-phase reaction technique, Sm and Bi co-doped LaBWO phosphors with high emission intensity and sensitive temperature sensing properties have been successfully synthesized. Based on XRD Rietveld refinement, the optimized crystal structure was used as the original model to calculate the band structure and partial density of states (PDOS) by density functional theory (DFT) calculations. The luminescence characteristics of Sm and Bi co-doped LaBWO phosphors were measured and analyzed.

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The surface frustrated Lewis pairs (SFLPs) on defect-laden metal oxides provide catalytic sites to activate H and CO molecules and enable efficient gas-phase CO photocatalysis. Lattice engineering of metal oxides provides a useful strategy to tailor the reactivity of SFLPs. Herein, a one-step solvothermal synthesis is developed that enables isomorphic replacement of Lewis acidic site In ions in InO by single-site Bi ions, thereby enhancing the propensity to activate CO molecules.

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We report a new type of highly efficient visible light-driven photocatalyst, Sm-activated BiOF nanoparticles, developed by a facile solid-state reaction technology. The corresponding phase compositions, morphological nature, and chemical states along with complementary theoretical calculation insights are investigated systematically. Upon 404 nm laser excitation, the photoluminescence performance of the synthesized nanoparticles is explored and the optimal properties are achieved in BiOF:Sm ( = 0.

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The Er/Yb-codoped NaLaMgWO phosphors were synthesized via a traditional high-temperature solid-state reaction method. The temperature sensing performance was thoroughly investigated by studying the temperature-dependent up-conversion (UC) emission intensity ratio in the range of 293-533 K. A remarkable enhancement of green UC emission, as well as enhanced temperature sensitivity, were observed by increasing the Yb concentration.

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Herein, Er3+-activated NaLaMgWO6 phosphors were prepared by a traditional high-temperature solid-state method. Based on the double perovskite structure of the NaLaMgWO6 host, we observe the desirable PL properties of Er3+. When excited at about 378 nm, the as-obtained materials can emit strong green light.

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Realization of simultaneous, efficient bifunctional application of thermochromic phosphors on light emitting diodes (LEDs) and as ratiometric thermometers is significant. Herein, doped Er ions are introduced as an activator into double perovskite LiLaMgWO host lattice. The developed phosphors can be efficiently excited by a near-ultraviolet LED chip and show bright green emission, mainly at 527 and 543 nm, as well as very low thermal quenching.

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Eu doped CdMoO super red emission phosphors with charge compensation were prepared by the traditional high temperature solid-state reaction method in air atmosphere. The interrelationships between photoluminescence properties and crystalline environments were investigated in detail. The 3D network structure which composed by CdO and MoO polyhedra can collect and efficiently transmit energy to Eu luminescent centers.

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A series of Tb3+, Eu3+-doped Sr2MgSi2O7 (SMSO) phosphors were synthesized by high temperature solid-state reaction. X-ray diffraction (XRD) patterns, Rietveld refinement, photoluminescence spectra (PL), and luminescence decay curves were utilized to characterize each sample's properties. Intense green emission due to Tb3+ 5D4→7F5 transition was observed in the Tb3+ single-doped SMSO sample, and the corresponding concentration quenching mechanism was demonstrated to be a diople-diople interaction.

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ZnSiO, ZnGeO, and CdAlO possess high electron density in their six-membered-ring nanotunnels, manganese from MnO was successfully doped into them, and green or blue phosphors were produced in air. It is nanotunnel A with high electron density that induces active sites for the reduction of Mn. Mn is captured and reduced to Mn on active sites by seizing two electrons from native defect V (V + Mn → V + Mn).

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Luminescent properties are affected by lattice environment of luminescence centers. The lattice environment of emission centers can be effectively changed due to the diversity of lattice environment in multiple site structure. But how precisely control the doped ions enter into different sites is still very difficult.

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A series of Sr2ZnWO6 phosphors co-doped with Eu(3+), Bi(3+) and Li(+) were prepared using the Pechini method. The samples were tested using X-ray diffraction and luminescence spectroscopy. The results show that the samples can be effectively excited by near-ultraviolet (UV) and UV light.

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