MATERIALS LETTERS
·
2014
·
IF 2.269
T. Wei,Y.Q. Wang,C.Z. Zhao,X.X. Dong,J.H. Wang
Filled tetragonal tungsten bronze (TTB) structure Sr 4 La 2 Ti 4 Nb 6 O 30 co-doped by Er 3+ and Yb 3+ (SLTN: x Er 3+ – y Yb 3+ ) ceramics with different x and y were synthesized, and their crystal structure, upconversion photoluminescence (UC-PL), and dielectric permittivity were investigated for the first time. Under 980 nm infrared (IR) excitation, bright single-band UC green (515–570 nm) emission was observed for SLTN: x Er 3+ – y Yb 3+ ( x =0.05, y =0), however, featured two-bands UC emission (515–570 nm and 640–690 nm) was confirmed for all SLTN: x Er 3+ – y Yb 3+ ( x =0.05, y ≠0) samples. Two-photon energy transfer process was proved through pumping laser power dependence of emission intensity measurement. It is believed that energy back transfer (EBT) process should be mainly responsible for the two-bands UC emission. In addition, the dielectric properties were also discussed for SLTN: x Er 3+ – y Yb 3+ system.
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2022
·Vol. 51
·期 12
·4685-4694
·
IF 4.569
Guixian Li,Yu Xue,Qinan Mao,Lang Pei,Hong He,Meijiao Liu,Liang Chu,Jiasong Zhong
Luminescent thermometers provide a non-contact method of probing temperature with high sensitivity and response speed at the nanoscale. Synergistic photoluminescence from different activators can realize high sensitivity for luminescent thermometers by finely selecting ions with specific crystallographic sites. Herein, the more temperature-sensitive Mn4+ and the less-sensitive Eu3+ (or Sm3+) activators are co-doped into a Ca2GdSbO6 matrix to form an effective thermometer, where Mn4+ and Eu3+ (or Sm3+) ions occupy the Sb5+ and Gd3+ sites, respectively. The co-doping of Eu3+ ions or Sm3+ ions leads to lattice expansion of Ca2GdSbO6 matrix and a tuned narrow emission from deep-red to orangish-red. According to the ratio of luminescence intensity, the maximal Sa and Sr values are 0.19 K−0 (347 K) and 1.38% K−( (420 K) for Ca2GdSbO6:Mn4+/Eu3+ probe and 0.26 K−p (363 K) and 1.55% K−( (430 K) for Ca2GdSbO6:Mn4+/Sm3+ probe thermometers, respectively. In addition, thermometers based on Mn4+ emission lifetimes can provide the highest relative sensitivity of 1.47% K−s at 425 K. Thus, the highly-temperature-sensitive Ca2GdSbO6:Mn4+/(Eu3+ or Sm3+) phosphor is a promising candidate for practical luminescence thermometers.
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Tian Tang,Jianing Ma,Jingyu Xue,Xiaoqiang Shen,Jinfei Chen,Linhan Yu,Vladislav Rac,Vesna Rakić,Xinbao Li,Hao Song,Xuesen Du
Industrial sources, such as steel and power activities continue to emit substantial amounts of CO, but have not received the same level of attention as mobile sources due to a lack of relevant regulations. This work reports that a commercial Pt/Al 2 O 3 catalyst used in vehicle CO catalytic converters may face severe selenium (Se) poisoning deactivation from industrial sources. The turnover frequency (TOF) of the Pt/Al 2 O 3 catalyst (250 °C) decreased from 2.18 s −1 to 0.12 s −1 with only 0.49 wt% (ICP) Se deposition. Se deposition causes the Pt 5d orbital shift to a higher energy state, raising the oxidation state of platinum. As a result, the back-donation from the 5d electrons of Pt to the 2π* antibonding orbital of the adsorbed CO molecule is inhibited, weakening the bonding between Pt/Al 2 O 3 and the CO antibonding orbital, thereby significantly reducing CO activation ability. DRIFTS results, combined with apparent and microscopic kinetics, indicate that the surface of Se deposited Pt/Al 2 O 3 catalyst remains O* available (500 K, θ O* = 0.16), and the rate-controlling step changes from O 2 + 2* → 2O* to CO + * → CO*. The work suggests that the application of CO catalytic oxidation technology for industrial source should fully consider the toxic effect of Se, but is often neglected.
✓ 已验证
DOI
高影响因子
CARBON
·
2023
·
IF 10.9
Xia Wang,Taifeng Shi,Chunlei Wan,Peng-an Zong,Zhenguo Liu,Wei Huang
Electromagnetic interference (EMI) shielding materials play a crucial role in safeguarding the reliable operation of electronic devices against electromagnetic waves (EW). Nevertheless, electronic devices inherently generate heat, and thermoelectric (TE) can convert heat into electricity, making them attractive as clean energy sources. Therefore, there is an increasing demand for high-performance EMI shielding materials with excellent TE properties. These materials can effectively mitigate EW pollution while simultaneously harnessing heat as electricity. Carbon cloth (CC) as one type of functional textile , has been widely explored as a potential material for EMI shielding, but rarely reported for TE application, due to low Seebeck coefficient . In this study, a facile electrodeposition method was employed to coat Bi 2 Te 3 layers onto the carbon fibers within carbon cloth. This innovative approach not only significantly improved the EMI shielding efficiency from 17.0 dB to an impressive 42.7 dB, but also imparted excellent TE performance to the film, as evidenced by a power factor of 42.4 μWm −1 K −2 . A four-legged TE module based on this film generates 35.5 nW of power at a temperature difference of 30 K, indicating its significant potential for powering low-consumption wearable electronics after integrating more TE legs. This study has paved the way for the development of a versatile material, that can mitigate EW pollution while simultaneously harnessing heat as electricity, by incorporating high TE performance inorganics into CC using a simple electrodeposition method.
✓ 已验证
DOI
高影响因子
Heliyon
·
2024
·
IF 3.4
Yanru Yin,Mengmeng Jiang,Lianhua Tian
A series of GdY 2 SbO 7 :Bi 3+ , Eu 3+ phosphors were prepared using the conventional solid-state reaction. In this study, the photoluminescence properties and temperature sensitivity of the samples were investigated. When Bi 3+ and Eu 3+ were codoped into GdY 2 SbO 7 , the intensity of Bi 3+ decreased with increasing Eu 3+ concentration, indicating a potential energy transfer from Bi 3+ to Eu 3+ . To examine the temperature sensitivity of the sample, its emission spectrum was investigated in the range of 300–500 K. Based on different temperature dependences of Bi 3+ and Eu 3+ , the relative sensitivity ( S r ) and absolute sensitivity ( S a ) of the samples were calculated using the fluorescence intensity ratio (FIR) and thermochromic methods. In FIR modes, S r based on I Eu 3+ /I Bi 3+ reached 1.26 % K −1 at 500 K, while S r on double excitation method reached 1.36 % K −1 at 340 K. In addition, according to the thermochromic properties of GdY 2 SbO 7 :Bi 3+ , Eu 3+ phosphor, the temperature-sensing ability of the sample was investigated, and S r reached a maximum value of 0.5996 % K −1 at 300 K.
✓ 已验证
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2021
·
IF 3.531
Juping Ma,Yan Jiao,Chongyun Shao,Yan Sun,Fei Yu,Lili Hu
In this work, Tb 3+ /Al 3+ co-doped and Al 3+ single doped silica glasses are taken as the research objects, and X-ray is used as the simulated light source to study the photodarkening mechanism. Detailed optical properties of the glasses before and after X-ray irradiation and the results of electron paramagnetic resonance (EPR) indicate that the photodarkening effect is attributed to the valence changes of Tb 3+ ions and the energy transfer between Tb 3+ ions and related defects. In addition, this work revealed the relationship between valence changes behavior of Tb 3+ ions and various defects in glass matrix materials, deepening the understanding of the photodarkening mechanism in Tb 3+ doped oxide glass. We envisage that our finding provides a depth-theoretical support for the synthesis of Tb 3+ -doped oxide matrix glass fibers with excellent optical and anti-photodarkening performance.
✓ 已验证
DOI
高影响因子
Soft Matter
·
2025
·
IF 2.8
Yun-song Zhou,Yang Sheng,Peng Zhang,Rong Zhang,Mark Bradley,Yi-xin Sun
The self-assembly of small molecules into supramolecular hydrogels is of great significance in mimicking biological systems. In this study, we investigated the formation and structure change of supramolecular hydrogels based on the self-assembly behavior of an achiral coumarin derivative (G1) and a chiral phenylalanine derivative (ALP). It was observed that G1 and ALP can self-assemble at various molar ratios, resulting in distinct nanostructured morphologies. Specifically, at a molar ratio of G1/ALP (4 : 1), the achiral G1 molecules initially bifurcate and diverge, ultimately forming a dendritic microstructure at the G1 termini. When the G1/ALP ratio was adjusted to 2 : 1, a chrysanthemum-like microstructure emerged. UV-light can destroy the self-assembled gel structure of different G1/ALP ratios, changing it from gel to sol. The emergence of these higher-order chiral structures during self-assembly was attributed to hydrogen bonding and π–π stacking interactions between the molecules. This research offers valuable insights into the understanding of biological self-assembly processes and the design of artificial biomedical materials.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2025
·
IF 6.3
Menghe Lou,Li Xiang,Guo Nie,Xueqing Luo,Renna Li,Feng Bi,Xiaole Weng,Zhongbiao Wu
The removal of carbon monoxide (CO) from sintering flue gases remains a significant challenge in industrial gas purification, requiring efficient catalytic systems. This study explores the use of TiO 2 synthesized under supercritical conditions in copper-based catalysts for low-temperature CO oxidation. Experimental results showed enhanced catalytic activity, with complete CO conversion at 120°C, primarily due to a higher Cu⁺ concentration in the catalyst. Characterization techniques (XPS, EPR, CO-DRIFT) confirmed a substantial increase in the Cu⁺ ratio in Cu/sc-TiO 2 (78%) compared to Cu/TiO 2 (71%) before thermal treatment. Additionally, the Cu/sc-TiO 2 -A catalyst exhibited smaller particle size and better dispersion, which contributed to the elevated Cu⁺ ratio after preheating. Thermal treatment increased the Cu⁺ ratio by 11% in Cu/sc-TiO 2 -A, compared to just 3% in Cu/TiO 2 -A, leading to a final Cu⁺ ratio of 89%, which enhanced catalytic activity. DRIFT and TPSR analyses indicated that the Cu/sc-TiO 2 catalyst generated CO during heat treatment, creating a micro-reduction environment that optimized copper valence states and active sites. This study highlights the potential of continuous hydrothermal flow synthesis for modulating catalyst valence states in industrial applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER COMPOSITES
·
2024
·
IF 4.8
Dayu Liang,Xiang Li,Yixiang Zhang,Jianlei Qi,Zhimin Lu
In this paper, carboxyl-terminated nitrile rubber (CTBN) and Nano cerium oxide (n-CeO 2 ) were used to toughen epoxy resin (EP), and the effects of toughening agents on the mechanical and thermal properties of EP were studied. Orthogonal experiments determined that the ideal toughener proportions are 20 wt% CTBN and 1 wt% n-CeO 2 , under which the resin demonstrated superior mechanical characteristics. The combined application of CTBN and n-CeO 2 significantly enhanced the resin's mechanical properties, surpassing the effects of individual particle toughening. Compared with pure EP, the impact, flexural, and tensile strengths of the resin-cured product synergistically toughened by CTBN and n-CeO 2 increased by 462%, 136%, and 110%, respectively, and the flexural and Young's moduli increased by 38% and 35%, respectively. Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) were used to characterize the cured resin. The results indicate that incorporating CTBN and n-CeO 2 reduces the reaction activation energy, thereby accelerating the curing reaction and facilitating its progression. The addition of nanoparticles enhances the maximum weight loss temperature of the cured resin, thereby improving its thermal stability. CTBN and n-CeO 2 particles create a uniform phase separation structure within the resin, enhancing its toughness and strength. Furthermore, the impact fracture mode of the cured resin transitions from brittle to tough fracture, demonstrating a significant toughening effect. This provides an effective method for the toughening modification of EP. Highlights The synergistic use of CTBN and n-CeO 2 enhances the toughness of EP. The incorporation of nanoparticles improves the thermal stability of the cured resin. The addition of CTBN and n-CeO 2 accelerates the curing reaction rate. The inclusion of toughening agents transforms the fracture mode of the cured resin from brittle to tough fracture.
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
·
2025
·
IF 6.3
Shengyu Wu,Zhongran Wu,Guofeng Li,Yongkai Liao,Shanna Lin,Zhao Liu,Chao Cai
The transport behavior of pollutants under dynamic groundwater conditions has attracted significant attention recently. However, there is limited research on the simultaneous effects of groundwater table fluctuations on the transport of co-existing pollutants, especially combined dense and light non-aqueous phase liquids (DNAPLs and LNAPLs). In this study, column experiments investigated toluene and dichloromethane transport in a controlled water table system with varying fluctuation conditions. Results showed that both dichloromethane and toluene accumulated near the groundwater table under static water table conditions, but the concentration of dichloromethane declined more rapidly than toluene due to differences in their physicochemical properties, such as solubility, density, and hydrophobicity. Groundwater fluctuations facilitated pollutants transportation towards deeper layers, potentially resulting in unforeseen increases in pollutant volatilization and downward fluxes. The interactions between dichloromethane and toluene, including competitive adsorption, enhanced dissolution, and altered kinematic viscosities, resulted in the reduced transport potential of dichloromethane while enhancing that of toluene. Furthermore, compared to dichloromethane, the initial upward fluctuation of the water table had a more pronounced impact on toluene due to its lower solubility and volatility. The downward transport risk index assessment indicated that among various factors considered, groundwater fluctuation amplitude exerted the most significant influence on pollutant migration risk. These new findings will provide important insights into understanding and assessment of the potential transport risk associated with combined LNAPLs and DNAPLs in the natural environment.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemPlusChem
·
2025
·
IF 2.8
Chunqiu Zhao,Qiang Chang,Fu Yin,Guowei Niu,Chenghua Zhang,Dan Liu,Bhekie B. Mamba,Alex T. Kuvarega
Graphical To enhance the catalytic performance of Zn−NC in the hydrogenation of CO to dimethyl ether, highly dispersed bimetallic catalysts are synthesized through the pyrolysis different metal-doped ZIF. The incorporation of secondary metals (Mn, Fe, Co, Ni, Cu) leads to distinct variations in catalytic performance. Among them, the introduction of Cu significantly improves catalytic activity. Highly dispersed bimetallic atomic-scale catalysts have garnered significant attention in syngas conversion filed due to the synergistic effects of the precisely structured bimetallic site, which facilitate the effective activation of CO. Despite their potential, synthesizing these catalysts to meet the specific application requirements remains challenging. Herein, various bimetallic catalysts were synthesized through the pyrolysis of the bimetallic ZIF precursors which were prepared by in situ doping of different metals (Mn, Fe, Co, Ni and Cu) into the ZIF-8 structure. In the presence of a highly dispersed and highly loaded Zn, the doping content in the ultimate second metallic catalysts varied between 0.15–1.20 wt % for different metals. The catalysts were systematically characterized using XRD, BET, TEM, XPS, Raman, ICP, and H 2 -TPD techniques. Among them, the Zn−NC regulated with Cu or Ni exhibited superior catalytic performance. Notably, the Cu−Zn−NC catalyst showed the highest activity, achieving a CO conversion of 32.8 % and optimal DME selectivity approaching 95.2 % in CO hydrogenation reactions. These enhanced performance metrics were attributed to the synergetic effects of bimetallic components. The incorporation of Cu not only preserved the original Zn−N structure but also preserved the catalytic performance unchanged. This preparation strategy is expected to filter out new research targets to use in diverse catalytic applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2025
·Vol. 15
·期 3
·1658-1664
·
IF 4.6
Xiuping Li,Jiaqi Wang,Bolin Yin,Kaihong Liu,Jingjing Zhao,Bo Jiang,Hexing Li
The hydrogenation of carbon dioxide into profitable chemicals is a viable path toward achieving the objective of carbon neutrality. However, the typical approach for hydrogenation of CO2 heavily relies on thermally driven catalysis at high temperatures, which is not aligned with the goals of carbon neutrality. Thus, there is a critical need to explore new catalytic methods for the high-efficiency conversion of CO2. Herein, we present a new class of catalysts, featuring phosphorus-doped amorphous ruthenium nanoparticles supported on copper nanoparticles, which capitalizes on the plasmonic effects of copper to achieve the photothermal transformation of CO2 to CO within a gas–solid flow system. Our findings indicated that the reaction efficiency in the presence of photothermal energy was over eight times greater than that with thermal energy alone. The catalyst system exhibited nearly 100% selectivity towards CO under mild conditions, with an impressive CO yield of 123.16 mmol g−1 h−1. This study highlights the significant potential of amorphous metal phosphides in photocatalytic CO2 hydrogenation under mild conditions and offers a fresh avenue for the robust catalysis of amorphous materials.
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）