CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Tianyu Guo,Xiaorong Nie,Jianping Du,Jinping Li
Methane oxidation is a strong exothermal reaction, the heat released from which can be utilized and the greenhouse effect caused by emitted methane, particularly low-concentration methane (LCM), can be further relieved. Presently, one of the key problems is to develop an efficient catalyst material for promoting LCM oxidation. Here, we synthesized an alumina with 2D feather-like lamella structure (FLAO), which is suitable for industrial applications. The samples were characterized by X-ray diffraction, scanning/transmission electron microscopy, X-ray photoelectron spectroscopy and nitrogen adsorption/desorption techniques. The results show that as-synthesized alumina has feather-shaped morphology and 2D slices structures, which form loose framework. Pd nanoparticles were easy to be anchored and well-dispersed on the surface of alumina. The FLAO-supported Pd catalysts exhibited high activity and stability. For 360000 mL g −1 h −1 space velocity, the LCM conversion research above 90% at 400 °C, and only decrease 8.6% after 50 h reaction at 450 °C, suggesting that as-synthesized 2D alumina slice has potential application for highly efficient removal of low-concentration methane from ventilation air.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2020
·
IF 2.779
Guonan Cui,Yanchun Yang,Ruilan Chen,Chengjun Zhu
Cations substitutions are known to make much significant contribution on achieving the high-quality kesterite Cu 2 ZnSn(S,Se) 4 thin films . And the optimal ratios of Mn, Ni and Co substitutions are reported to be ~0.05, belong to the low doping to reduce their defect density , which looks like to some extent the effect of Na doping. In this study, learning the research experience of alkali metal doping, we introduced the extra trace Mn 2+ ion into the precursor solution without affecting the compositions of other elements (i.e. Cu, Zn, and Sn), and the effect of trace addition on properties of the absorber layer was also studied. It was discovered that crystalline, electrical properties, and hole carrier concentration of Cu 2 ZnSn(S,Se) 4 thin films increased with an increase of Mn incorporation, and the best doping ratio of Mn/(Cu + Zn + Sn) was considered to be 0.03. In addition, the effect of extra trace Mn-doping on the film thickness and elemental compositions of Cu 2 ZnSn(S,Se) 4 absorber layer were studied in detail.
研究领域:
材料科学
·
半导体物理
·
薄膜制备
·
光伏材料
·
固体化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 48
·期 13
·18876-18883
·
IF 5.532
Zhixin Ma,Yang Qi,Jun Wang,Xiaoguo Bi,Xu-dong Liu,Xiaodong Li,Ji-guang Li,Xudong Sun
SrTiO 3 is a promising thermoelectric material for applications in harsh environments, owing to its excellent thermoelectric (TE) properties and high-temperature stability. The effect of annealing in carbon powders on the TE properties of SrTiO 3−δ in the [111] direction was experimentally investigated and analysed using first-principles calculation. The electrical conductivity of the SrTiO 3−δ single crystals in the [111] direction increases with an increase in annealing temperature in the range of 1573–1673 K, which is opposite to that in the [510] direction as shown in a previous experiment. This is attributed to the different variation trend of carrier concentration. First-principle calculation results show that the carrier concentration in the [111] direction increases with increasing oxygen vacancy concentration, but it is the opposite in the [510] direction. Strong anisotropy of carrier concentration should be caused by the difference in atomic arrangement, making difference in the amount of free electrons that maybe constrained at high oxygen vacancy in different directions. Although the SrTiO 3−δ single crystal annealed at 1573 K shows a lower electrical conductivity, it obtains higher power factor with the maximum value of 2.24 mW m −1 K −2 at 323 K, which is predominantly due to its higher effective mass. It also yields the highest ZT value of 0.18 at 873 K owing to the lower thermal conductivity . The results of this study are imperative for the design and development of perovskite TE materials.
研究领域:
材料科学
·
凝聚态物理
·
热电材料
·
晶体学
·
固体化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 48
·期 22
·33967-33975
·
IF 5.532
Ya-nan Li,Ping Wu,Shiping Zhang,Yili Pei,Jinguang Yang,Sen Chen,Li Wang
Adding nanoparticles is a method to regulate the performance of thermoelectric materials. Ca 3 Co 4 O 9 /x MoSi 2 (x = 0, 0.05, 0.10, 0.13, and 0.16) was synthesized by a wet chemical method combined with atmospheric pressure sintering. The XRD and SEM results reveal that there are no other reaction in the samples. The grain size of all samples decrease with increasing MoSi 2 content, and all presented a similar flake morphology. The influence of MoSi 2 on the thermoelectric performance of Ca 3 Co 4 O 9 is systematically analysed. The appropriate addition of nano-MoSi 2 particles can increase the carrier concentration and enhance conductivity of Ca 3 Co 4 O 9 . The electrical conductivity of Ca 3 Co 4 O 9 /0.05 MoSi 2 is 83.16 Scm −1 , which is 49.2% higher than that of Ca 3 Co 4 O 9 at 1080 K. The Seebeck coefficient of the Ca 3 Co 4 O 9 /0.16 MoSi 2 sample reaches 197.56 μVK −1 at 980 K, which is significantly better than that of previously reported samples prepared by the same method. Moreover, combined with the experimental results and the analysis of the effective medium theory model, the addition of MoSi 2 can effectively debase the thermal conductivity of Ca 3 Co 4 O 9 . The thermal conductivity of Ca 3 Co 4 O 9 /0.16 MoSi 2 (∼1.26 Wm −1 K −1 , 1080 K) samples decrease greatly, which is attributed to the influence of interfacial thermal resistance and pores in the Ca 3 Co 4 O 9 /MoSi 2 . The ZT value of the Ca 3 Co 4 O 9 /0.05 MoSi 2 sample increases by 44.4% compare with that of Ca 3 Co 4 O 9 and reaches 0.26 at 1080 K. These results demonstrate that adding an appropriate amount of MoSi 2 particles is one of the methods to enhance the thermoelectric performance of Ca 3 Co 4 O 9 ceramic samples.
研究领域:
材料科学
·
凝聚态物理
·
无机非金属材料
·
能源材料
·
热电转换
✓ 已验证
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Yanzhi Zhao,Juying Zhou,Fuhou Lei,Haitang Xu,Jianfang Lu,Zaiying Huang,Qin Huang,Pengfei Li
In this work, amphiphilic acrylicpimaric acid polyglycol ester (APAPG) was synthesized by steglich esterification method. The structure transformation and aggregation behaviors of APAPG in water were investigated by Rayleigh light scattering (RLS) technique in a heating and cooling cycle. For concentration above critical micelle concentration (CMC), a reversible transition from micelle to aggregation was observed. The structure transformation process involved irreversible aggregation and disaggregation processes at low temperature and a reversible aggregation process at high temperature when the concentration closed to CMC. Accordingly, the information about each structure transformation behavior in the concentration far below CMC during heating process including individual unimers, aggregation and disaggregation were thoroughly revealed. However, the structure transformation behavior is irreversible in the cooling process. The structure transformation and aggregation behaviors were assessed by dynamic light scattering (DLS), microcalorimetry and scanning electron microscopy (SEM) techniques. The results indicate that the RLS technique can provide detailed information about structural evolution at molecular level of polymer chains.
研究领域:
高分子化学
·
胶体与界面化学
·
药物递送系统
·
生物材料
·
纳米医学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 23
·12429-12437
·
IF 14.511
Shuang Li,Yunxiang Hou,Di Li,Bo Zou,Qingtang Zhang,Yang Cao,Guodong Tang
SnSe is considered one of the most intriguing new thermoelectric materials. Polycrystalline SnSe offers a wide range of thermoelectric applications due to its facile synthetic processing and machinability. Herein, we have achieved a high average ZT of 0.8 as well as a high peak ZT of 1.86 in solution-synthesized porous Zn and Ga codoped SnSe nanosheets, generating a maximum energy conversion efficiency of 13.3%. High-density micro/nanopores are induced in the SnSe matrix, which are more effective for scattering phonons and reducing the thermal conductivity. The high density of micro/nanopores, nanosheet structure and dislocations contribute to an ultralow lattice thermal conductivity (0.157 W m−1 K−1 at 873 K). Meanwhile, Ga incorporation can induce band convergence and create resonance levels, producing a large Seebeck coefficient. Ga and Zn codoping contributes to a sharp increase in carrier concentration and an obviously increased electrical conductivity. The enhanced Seebeck coefficient and increased carrier concentration help in achieving a significant enhancement of the power factor over a wide temperature range in the porous Zn and Ga codoped SnSe nanosheets. Consequently, high thermoelectric performance is realized over a wide temperature range via the decoupling of electron–phonon transport in SnSe. This work opens up a great opportunity for designing prospective materials for thermoelectric applications with the aid of the solution synthesis route.
研究领域:
材料科学
·
凝聚态物理
·
纳米科技
·
能源材料
·
半导体物理
·
热电转换
·
无机功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF SUPERCRITICAL FLUIDS
·
2022
·
IF 4.514
Jianqiao Yang,Jiyuan Sun,Shuyuan Bai,Hao Wu,Shuzhong Wang,Yanhui Li,Wenhao Ma,Donghai Xu
To improve the corrosion resistance of component materials in supercritical water oxidation (SCWO) environment, a 15 µm Cr coating was prepared on Alloy 625 by magnetron sputtering, and the effect of oxygen concentration (0 M, 0.16 M, and 0.94 M) on the stability of the Cr coating in an SCW environment was investigated. Results show that the stability of the Cr 2 O 3 layer strongly depends on the oxygen concentration in the exposure environment. The protective Cr 2 O 3 layer was transformed to soluble Cr(VI) species and dissolved in SCW containing 0.94 M oxygen. Except for Cr 2 O 3 , some Fe/Ni containing oxides were also detected. The stability of the Cr coating in SCW with different concentrations of oxygen is discussed.
研究领域:
材料科学
·
腐蚀与防护
·
表面工程
·
能源环境工程
·
高温化学
✓ 已验证
DOI
高影响因子
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
·
2018
·Vol. 215
·期 11
·1700905
·
IF 1.795
Shuping Deng,Decong Li,Liping Zheng,Yu Tang,Zhong Chen,Luqi Sun,Wenting Liu,Lanxian Shen,Shukang Deng
In this work, the effect of Cd and Sn atoms partly substitution for Zn on among crystal growth, thermal stability, mechanical, and electrical transport property in β-Zn 4 Sb 3 is reported. In a series of samples prepared from the atomic ratios of Zn:Sb:Cd:Sn = 4.4:3: x :3 ( x = 0.2, 0.4, 0.6, and 0.8). Carrier concentration of all samples varies from 4.52 × 10 19 to 6.42 × 10 19 cm −3 as carrier mobility changes from 58.27 to 67.93 cm 2 V −1 s −1 at room temperature. As a result, electrical transport properties of the samples are optimized by Cd Sn co-doped. The experimental density of all the samples varies from 6.26 × 10 3 to 6.34 × 10 3 kg m −3 consistent with the theoretical value. The weight loss and melting point of the sample are determined to discuss thermal stability in the heating process in air, indicating that the single crystals β-Zn 4 Sb 3 possess an excellent thermal stability and it is practical importance in the TE application at high temperature. Consequently, the maximal power factor of 1.70 × 10 −3 W m −1 K −2 is achieved at 540 K for the sample with initial Cd content x = 0.2, which is enhanced by 40% compared with the single-doping system in β-Zn 4 Sb 3 .
研究领域:
材料科学
·
热电材料
·
固体物理
·
无机化学
·
功能材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·Vol. 46
·期 3
·2845-2852
·
IF 3.45
Quansheng Wu,Quan Zhao,Penghui Zheng,Wenbo Chen,Dongfeng Xiang,Ziyu He,Qiang Huang,Jianyan Ding,Jiangcong Zhou
Lithium-containing silicate compounds have attracted so much attention in recent years for applications in energy storage and illumination source due to their rigid structure and good electrical conductivity . In this study, a Eu 3+ doped lithium-containing silicate red phosphor , Li 2 Ca 4 Si 4 O 13 :Eu 3+ , was explored by using structural computational simulations and systematic experiments for multifunctional applications. As a result, due to the quite non-central symmetry of the Ca 2+ sites (C 1 symmetry), the strong 4f-4f excitations in near ultraviolet region were observed. Under near ultraviolet and cathode ray light excitation , Li 2 Ca 4 Si 4 O 13 :Eu 3+ phosphor has an efficient red emission with good thermal stability and ageing resistance. Furthermore, Li 2 Ca 4 Si 4 O 13 :Eu 3+ phosphor exhibits a concentration-sensitive behavior induced by the change of site symmetry. The results show that it is feasible to develop near-ultraviolet and cathode ray light excited red phosphors in lithium-containing silicate compounds.
研究领域:
材料科学
·
无机化学
·
固体物理
·
光电功能材料
·
发光材料
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Yaping You,Ya Zheng,Zesheng Pan,Yunluo Wang,Tianrui Zhou,Minghui Wang,Haijie Chen,Wan Jiang,Lianjun Wang
White light-emitting diode (WLED) has been widely used as solid-state lighting in recent years, with the advantages of energy saving, high luminous efficiency , and safety. Red phosphors are crucial to the color rendering index of WLED, and Eu 3+ -activated red phosphors can significantly improve the chromaticity performance of WLED. In this work, a series of new orange-red emitting BaLiZn 3 (PO 4 ) 3 : Eu 3+ phosphors were synthesized through high-temperature solid-state reaction method. The phase composition , crystal structure, morphology and photoluminescence properties of BaLiZn 3 (PO 4 ) 3 : Eu 3+ samples were investigated. The phosphors can be effectively excited by the violet light at 394 nm and emit orange-red lights corresponding to the electric dipole transition (5D 0 →7F 1 ) at 594 nm. The optimal doping concentration of Eu 3+ ions was about 5 mol%. The concentration quenching was caused by the electric dipole-dipole interaction between Eu 3+ ions. Temperature-dependent PL spectra indicate that BaLiZn 3 (PO 4 ) 3 : Eu 3+ has excellent emission and color stability at high temperatures. The color coordinates were calculated and fall in the orange-red luminescent area. The color purity is about 98.3 %, and the correlated color temperature is 1710K. These results indicate that the new orange-red phosphor BaLiZn 3 (PO 4 ) 3 : Eu 3+ has potential application prospects in WLED.
研究领域:
材料科学
·
发光材料
·
固体照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Siqi Wang,Zhi Yang,Yuejun Sun,Yu Xiao,Li-Dong Zhao
PbTe-based thermoelectric materials are considered to be a medium-temperature thermoelectric candidates and the high-performance n -type PbTe is urgently to be developed to match its p -type counterpart on account of practical application. Herein, we firstly optimized the carrier density of n -type PbTe through Sb doping, and obtained a maximum ZT value of ∼1.0. Then, based on the optimized carrier density, we introduced ternary compounds AgSb(Se, Te) 2 to suppress the lattice thermal conductivity . Minimum lattice thermal conductivity of n -type PbTe was reduced as low as ∼0.53 W m −1 K −1 and ∼0.62 Wm −1 K −1 through introducing AgSbSe 2 and AgSbTe 2 , respectively. Combining the maintained electrical properties with suppressed thermal conductivity , maximum ZT values ∼1.2 and ∼1.3 were obtained in PbTe+2%AgSbSe 2 and PbTe+2%AgSbTe 2 , respectively. This work provides an effective strategy of synergistically balancing charge and phonon transports in n -type PbTe with ternary AgSb(Se, Te) 2 compounds.
研究领域:
材料科学
·
热电转换
·
凝聚态物理
·
半导体物理
·
功能材料
·
能量转换材料
✓ 已验证
DOI
高影响因子
Journal of Oceanology and Limnology
·
2021
·Vol. 39
·期 5
·1622-1633
·
IF 1.265
Qu Yang,Xu Kuidong,Li Tao,Wang Maoyu,Zhong Huan,Chen Tianyu
The ocean is an important inventory of anthropogenic mercury (Hg), yet the history of anthropogenic Hg accumulation in the ocean remains largely unexplored. Deep-sea corals are an emerging archive of past ocean chemistry, which take in sinking or suspended particulate organic matter as their food sources. Such organic matter would exchange Hg with the local seawater before being consumed by the deep, sea corals. As such, the organics preserved in the coral skeleton may record the Hg evolution of the ambient seawater during the time of coral growth. Here, we report the first data on Hg concentrations variability of a deep-sea proteinaceous coral in the oligotrophic North Pacific at the water depth of 1 249 m, in attempt to understand the transfer of anthropogenic Hg into the deep Pacific ocean over the last seven centuries. We find that the Hg concentrations of different coral growth layers have remained relatively constant albeit with considerable short-term variability through time. The overall stable Hg concentration of the last seven centuries recorded in our sample suggests that anthropogenic pollution is not yet a clearly resolvable component in the deep oligotrophic North Pacific waters, in agreement with recent estimation from modelling works and observational studies of modern seawater profiles. As there is hardly an unambiguous way to separate anthropogenic Hg from the natural background based on recent seawater profiles, our historical data provide valuable information helping to understand the oceanic cycle of Hg through time.
研究领域:
海洋地球化学
·
环境科学
·
古气候学
·
生物地球化学循环
·
深海生态学
✓ 已验证
DOI
高影响因子