INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·Vol. 44
·期 3
·1586-1596
·
IF 4.229
Tianyu Zhao,Zipeng Xing,Ziyuan Xiu,Zhenzi Li,Shilin Yang,Qi Zhu,Wei Zhou
TiO 2-x /g-C 3 N 4 /CdS ternary heterojunctions are fabricated through thermal polymerization-chemical bath deposition combined with in-situ solid-state chemical reduction approach. The prepared materials are characterized by X-ray diffraction, Fourier transform infrared spectra , scanning electron microscopy, transmission electron microscopy , nitrogen adsorption-desorption, and X-ray photoelectron spectroscopy. The results show that the ternary heterojunctions are formed successfully and CdS quantum dots (QDs) and TiO 2 are anchored on surface of g-C 3 N 4 nanosheets simultaneously. The visible-light-driven photocatalytic degradation ratio of Bisphenol A and hydrogen production rate are up to 95% and ∼254.8 μmol h −1 , respectively, which are several times higher than that of pristine TiO 2 . The excellent visible-light-driven photocatalytic activity can be ascribed to the synergistic effect of TiO 2−x , g-C 3 N 4 and CdS QDs which extend the photoresponse to visible light region and favor the spatial separation of photogenerated charge carriers.
研究领域:
材料科学
·
光催化
·
纳米材料
·
环境催化
·
能源化学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2020
·
IF 4.551
Junjie Zhou,Hao Liu,Yichao Lin,Chen Zhou,Aisheng Huang
A well-shaped Ce (IV)-based metal organic framework (Ce-BDC) is prepared under solvothermal method. The influence of synthesis time, temperature and the amount of acetic acid (HAc) as a modulator is studied to develop a new strategy for the synthesis of well-shaped Ce-based MOF. The relationship between the synthesis parameters and morphology as well as crystallinity of Ce-BDC is investigated by XRD and SEM. Furthermore, the obtained well-shaped Ce-BDC shows a CO 2 uptake capacity of 2.28 mmol g −1 at 0 °C and 1.0 bar. Meanwhile, the breakthrough curve behaviors of Ce-BDC are investigated for a CO 2 /CH 4 and CO 2 /N 2 mixture gas . It is found that the Ce-based MOF adsorbs CO 2 under ambient temperature and pressure, but completely excludes CH 4 and N 2 , suggesting that it is a promising adsorbent for efficient separation of CO 2 from natural gas.
研究领域:
材料科学
·
无机化学
·
多孔材料
·
气体分离
·
环境催化
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Kaitong Liu,Jian Han,Fuming Li,Congcong Jin,Zhihua Yang,Miriding Mutailipu,Shilie Pan
A case of hydrous borate with the formula of Ba 2 B 13 O 19 (OH) 5 ·5H 2 O was synthesized by the traditional hydrothermal method . It crystallizes in the chiral P 1 space group and has a unique two-dimensional 2 [B 13 O 19 (OH) 5 ] ∞ layer that is constructed by the hydrogen involved [B 13 O 22 (OH) 5 ] fundamental building blocks (FBBs). The Ba atoms and H 2 O molecules are filled in the three-dimensional pore constructed by the 2 [B 13 O 19 (OH) 5 ] ∞ layer. Interestingly, Ba 2 B 13 O 19 (OH) 5 ·5H 2 O is the first case of hydrous borates that has the above rare [B 13 O 22 (OH) 5 ] FBB and 2 [B 13 O 19 (OH) 5 ] ∞ layer, which enriching the structural chemistry of borate system. The diffuse reflection spectrum result shows that the ultraviolet (UV) cutoff edge of Ba 2 B 13 O 19 (OH) 5 ·5H 2 O is below 200 nm. Its second harmonic generation (SHG) response is approximately 1.0 times that of potassium dihydrogen phosphate at the 1064 nm fundamental wavelength and it is also phase-matchable. Both results indicate that the title compound is a nonlinear optical crystal for UV spectral region. Theoretical simulation calculation shows that the occupied VE states are mainly contributed by the O-2p orbitals, and therefore [B 13 O 22 (OH) 5 ] groups are the main sources of SHG effects.
研究领域:
无机化学
·
材料科学
·
晶体工程
·
光学材料
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固体化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·Vol. 44
·期 17
·21000-21003
·
IF 3.057
Jie Zhang,Zhenxing Yue,Yu Luo,Longtu Li
A cofired trilayer ceramic architecture showing as MgTiO 3 /TiO 2 /MgTiO 3 was designed to realize temperature-stable and ultrahigh- Q microwave dielectrics in the typical MgTiO 3 -TiO 2 system. The effects of TiO 2 content on the microwave dielectric properties of cofired trilayer ceramics were studied. Through the design of cofired trilayer architecture, the chemical reactions between MgTiO 3 and TiO 2 were limited within a narrow region of MgTiO 3 /TiO 2 interfaces (~ 15 µm in width), which could be beneficial for optimizing the microwave dielectric properties. Excellent characteristics of ε r ~ 18.38, Q×f value ~ 169,900 GHz and τ f ~ − 1 ppm/°C were gained for the MgTiO 3 /TiO 2 /MgTiO 3 ceramic architectures stacked with 1.63 vol% TiO 2 . The current work could serve as new strategies to develop high-performance dielectric resonators and multilayers for 5G wireless communication applications.
研究领域:
材料科学
·
无机非金属材料
·
电子陶瓷
·
微波介质材料
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功能陶瓷
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 46
·期 12
·20173-20182
·
IF 3.83
Shujie Gai,Haifeng Zhu,Peixin Gao,Cheng Zhou,Zihui Kong,Maxim S. Molokeev,Zhiyong Qi,Zhi Zhou,Mao Xia
Currently, phosphor-converted LEDs (pc-LEDs) are revolutionizing the industry of plant growth lighting. To meet the requirements of this technology, phosphors with tunable photoluminescence , high thermal stability and luminous intensity are required. Herein, we found that the simple substitution of yttrium for lanthanum in La 2 MgTiO 6 :Mn 4+ (LMT:Mn 4+ ) system could satisfy above three criteria simultaneously. The photoluminescence properties can be regulated by continuously controlling the chemical composition of La 2-x Y x MgTiO 6 :Mn 4+ solid solution . The La sites are occupied by Y ions , causing a significant blue shift in the emission spectra which owing to the change of local crystal field strengthen. Meanwhile, the thermal stability and decay lifetimes are also varied due to the variation of local structure and band gap energy. The thermal stability of the material reaches 83.5% at 150 °C, which is better than the reported La 2 MgTiO 6 :Mn 4+ and Y 2 MgTiO 6 :Mn 4+ phosphors. The electronic luminescence (EL) of pc-LED devices using La 2-x Y x MgTiO 6 :Mn 4+ red phosphor is evaluated, which matching the absorption regions of plant pigments well, reflecting the superiority of the studied phosphors in plant growth lighting areas.
研究领域:
材料科学
·
光电子学
·
无机化学
·
农业工程
·
固体物理
·
发光材料
·
植物生理学
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2019
·
IF 3.192
Lu Zhu,Yousen Zhu,Xuanru Ren,Ping Zhang,Jianghao Qiao,Peizhong Feng
MoSi 2 -MoB-ZrO 2 composite powders are one-step synthesized prepared by self-propagating high-temperature synthesis (SHS), which are further utilized to prepare the oxidation protective coatings by spark plasma sintering (SPS) method on molybdenum substrate. Microstructure and properties of the coatings were investigated and determined. Oxidation behavior of the coatings at high temperature was also studied. The results showed that the composite coating is dense and crack-free due to the addition of ZrO 2 , which is beneficial for the decrease of mismatch in coefficient of thermal expansion, and no void exists in the diffusion layer owing to the diffusion of Si, which is inhibited by adding MoB. Compared with the pure MoSi2 coating, the high hardness of the composite coating is enhanced by about 20% while the fracture toughness of the composite coating is improved by about 25%, which makes the occurrence of intergranular fracture , crack deflection and crack bridging. After oxidation at 1400 °C for 80 h, MoSi 2 coating failed while xMoSi 2 -MoB-3ZrO 2 (x = 3, 4, 5) composite coating still kept its protective effect. Only a little substrate is consumed during oxidation and improved oxidation resistance is gained by MoSi 2 -MoB-ZrO 2 composite coating. 3MoSi 2 -MoB-3ZrO 2 coating shows the relatively best oxidation resistance due to the formation of crack-free oxide film on the surface of the coating.
研究领域:
材料科学
·
表面工程
·
高温氧化
·
陶瓷涂层
·
粉末冶金
✓ 已验证
DOI
高影响因子
CRYSTAL RESEARCH AND TECHNOLOGY
·
2015
·Vol. 50
·期 4
·312-318
·
IF 0.935
Yadong Hu,Yinghua Zhou,Xurong Xu,Ruikang Tang
The evolution of amorphous calcium carbonate (ACC) into crystals in ethanol/water binary solvents under ambient temperature was investigated, and it was found to depend on the volume ratio of ethanol to water (R). Calcite remained dominant when the amount of water was high (R = 1/3). A slight change in the amount of ethanol (R = 3/1) could lead to a dramatic change in the polymorph from calcite to aragonite. However, when poly (allylamine hydrochloride) (PAH) was added at R = 3/1, almost pure vaterite could be obtained, which has a specific morphological variation (from hollow microspheres to cloud-like). This study provides an alternative polymorphic route for the CaCO 3 mineral by using the evolution of ACC in different solvent environments, which provides some useful clues for understanding the importance of kinetic control of the morphologies and polymorphs of a wide range of inorganic materials. In addition, this simple mild phase-controlled synthetic method could be scaled up as a green chemistry route for the industrial production of different polymorphs of CaCO 3 .
研究领域:
材料化学
·
结晶学
·
纳米材料
·
生物矿化
·
绿色化学
·
功能材料
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 38
·22064-22071
·
IF 12.732
Wenda Zhang,Jie Feng,Fengqi Lu,Alberto J. Fernández-Carrión,Hui Fu,Xiaojun Kuang
Na-doped melilite-type silicate Sr2MgSi2O7 was reported to display high oxide ion conductivity. In this work, through multiple complementary techniques including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, solid-state 29Si and 23Na nuclear magnetic resonance spectroscopy, and DFT calculations of defect formation energies, we found that it is hard to replace Sr with Na in Sr2MgSi2O7, and the Sr2−xNaxMgSi2O7−0.5x compositions formed mixed crystalline Sr2MgSi2O7 and Na-containing glassy phases. AC impedance spectroscopy measurements indicated that the ionic conduction in Sr2−xNaxMgSi2O7−0.5x could be from Na+ ions in the glassy phase, instead of the oxide ions.
研究领域:
材料科学
·
固体离子导体
·
无机非金属材料
·
能源材料
·
电化学
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2019
·Vol. 125
·期 3
·158
·
IF 1.784
Gao Dong-Sheng,Gao Xiang-Dong,Wu Yong-Qing,Zhang Tong-Tong,Yang Jing-Nan,Li Xiao-Min
Co doped BaSnO 3 films [BaSn 1 − x Co x O 3 (0 ≤ x ≤ 0.50), i.e., BSCO] have been grown on MgO single-crystal substrates via pulsed laser deposition. Effects of the Co-doping level on the crystallinity, the microstructure, and optical properties of the BSCO films are investigated. All the BSCO films are of high crystallinity and grown epitaxially on MgO substrates. The lattice parameter of the (200) plane drops linearly with the increase of the ‘ x ’ value. The Co doping is found to increase the film roughness and the grain size, and a RMS roughness of 8.33 nm and grain size up to 100 nm are observed in the film with x = 0.50. The low Co-doping level ( x = 0.05, 0.1) has slight anti-reflection effects on the incident visible light, and the Co-doping level higher than 0.2 reduces the optical transmittance significantly. The optical bandgap shows a first-rising then falling trend with the increase of the Co content, and the lowest bandgap of 1.94 eV is realized in the BSCO film with x = 0.50.
研究领域:
材料科学
·
凝聚态物理
·
薄膜制备
·
光学材料
·
功能氧化物
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Peng Hou,Ke Chen,Xudong Wang,Xiaofei Hu,Bing Li,Ming Liu,Xiao (Matthew) Hu,Yujie Song
The rapid development of high-performance materials has garnered considerable attention in addressing electromagnetic pollution . The construction of core-shell heterostructures is an effective approach for regulating the electromagnetic parameters of absorbers. However, these heterostructures usually lack a direct channel for charge transport between the core phase and the adhesive shell phase. Herein, Fe 2 AlB 2 @FeAl-layered double hydroxides with core-shell heterostructures were prepared using a top-down approach. The tightly connected FeAl-LDHs nanosheets to the Fe 2 AlB 2 parent phase improved electronic transport. Compared with raw Fe 2 AlB 2 , the spherical absorber with an embroidered structure demonstrated stronger reflection loss (-15.6 dB for Fe 2 AlB 2 , −58.6 dB for Fe 2 AlB 2 @FeAl-LDHs) and a broader effective absorption bandwidth (2.2 GHz for Fe 2 AlB 2 , 3.6 GHz for Fe 2 AlB 2 @FeAl-LDHs) due to the enhanced dielectric and magnetic losses. This study presents a practical method for designing new controllable core-shell heterostructures for electromagnetic wave-absorbing materials.
研究领域:
材料科学
·
电磁学
·
纳米材料
·
功能材料
·
复合材料
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2015
·
IF 2.288
J.L. Wang,E.H. Song,M. Wu,W.B. Dai,S. Ye,Q.Y. Zhang
Selectively enhanced green upconversion (UC) and near-infrared (NIR) downconversion (DC) emissions of Er 3+ by Yb 3+ -Mn 2+ dimer sensitizing have been demonstrated in Er 3+ /Yb 3+ /Mn 2+ tri-doped spinel MgGa 2 O 4 upon excitation of 980 nm laser diode (LD). By optimizing the doping rate of Mn 2+ , the intensity ratio of green to red UC emission intensities of Er 3+ (G/R) could be enhanced about 10 times. Meanwhile, the 1.5 μm NIR DC emission could also be increased about 3.6 times in this system. The DC and UC emission properties, UC mechanism, as well as the enhancing mechanism have been investigated and discussed in detail. A selectively enhancing mechanism based on Yb 3+ -Mn 2+ dimer sensitizing is proposed to explain the selectively enhancing phenomena. This work could inspire the design of novel UC materials for various applications, such as temperature sensors and optical transmission, etc.
研究领域:
光学材料
·
生物医学光子学
·
无机功能材料
·
分子影像
·
转化医学
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2019
·Vol. 7
·期 20
·1900774
·
IF 7.125
Xin Zhang,Dengbao Han,Chenhui Wang,Imran Muhammad,Feng Zhang,Ali Shmshad,Xulan Xue,Wenyu Ji,Shuai Chang,Haizheng Zhong
The in situ fabricated perovskite nanocrystals (PNCs) obtained through spin-coating a precursor solution are suitable candidates to achieve efficient perovskite light emitting diodes (PeLEDs). In this work, the solvent effects of on-chip crystallization are investigated by correlating the nucleation and growth process of in situ fabricated formamidinium lead iodide (FAPbI 3 ) nanocrystals with their optical and electronic properties. The FAPbI 3 nanocrystals obtained from a precursor solution in γ-butyrolactone (GBL) are smaller than those obtained from N , N -dimethylformamide and dimethyl sulfoxide, and the relatively weak coordination between GBL and the precursor molecules enables reduced defect states in the resulted PNCs with enhanced photoluminescence properties. A modified LaMer model is proposed to describe the solvent effects in the on-chip crystallization process. Based on these understandings, red emissive FA 0.87 Cs 0.13 PbI 3 nanocrystal films with absolute photoluminescence quantum yields up to 70% are realized. Finally, an efficient PeLED with maximum luminance of 218 cd m −2 and peak external quantum efficiency of 15.8% is achieved with good reproducibility.
研究领域:
材料科学
·
纳米科技
·
光电子学
·
半导体器件
·
凝聚态物理
✓ 已验证
DOI
高影响因子