ACTA MATERIALIA
·
2022
·
IF 9.209
Qian Liu,Ke-Feng Liu,Qi-Qi Wang,Xiao-Cun Liu,Fang Yu,Jian Liu,Yuan-Yuan Su,Sheng-Qing Xia
In this report, for the first time TiNiSi-type Zintl phases with the nominal formulae of ALiSb (A = Ca, Sr, Eu, Yb) were systematically investigated on their thermoelectric properties. The results indicated that ALiSb Zintl phases possessed intrinsically low lattice thermal conductivity despite the simple structure. In combination of thorough crystallographic and theoretical investigation, rattling-like scattering behavior originating from the Li atoms was suggested. As a result, the pristine ALiSb materials featured decent zT values of 0.4–0.7 at 823 K. With the electrical and thermal transport properties further optimized by configuring the solid solutions such as Sr 0.8 Eu 0.2 LiSb, the material approached a maximum zT up to 1.2 at the same temperature. These breakthroughs are distinct from the previous knowledge that low thermal conductivity in Zintl phases is usually realized through complex crystal structures, and for compounds with simple structures such as the TiNiSi type it is common to have poor thermoelectric performance. Owing to such a rattling-like scattering behavior, now light-element containing Zintl phases can be a promising resource for thermoelectric considerations as well. The mechanism is surely interesting and worth of in-depth investigation.
研究领域:
材料科学
·
热电材料
·
固体化学
·
晶体学
·
能源材料
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Ayesha Idrees,Ali Shan,Waqas Qamar Zaman,Ali Mohsin,Zain Abbas,Tanvir Shahzad,Atif Shakeel,Shuguang Lyu
M-metal (Ca and Cu) doped Ca-Fe 2 O 3 and Cu-Fe 2 O 3 catalysts were synthesized using solvothermal method. The Ca-Fe 2 O 3 and Cu-Fe 2 O 3 catalysts were characterized by XRD, Raman spectroscopy , SEM , TEM and XPS spectroscopy. The catalytic performance of 6%Ca-Fe 2 O 3 and 5%Cu-Fe 2 O 3 catalysts for trichloroethylene (TCE) removal were improved by M-metal doping leading to TCE removal at 99.8% in 1 h, which were three folds greater than by simple a- Fe 2 O 3 in the presence of persulfate (PS). Ca and Cu doping formed defective structure and created more oxygen vacancies thereby generating abundant active species during PS activation process. Further, the influence of catalysts’ dosage, oxidant dosage, solution pH, inorganic anions, and dissolved oxygen were evaluated. Complete removal of TCE was also obtained at weak alkaline pH condition. The greater specific surface area and the improved electrical conductivity was attributed to the huge generation of O 2 •– and 1 O 2 species which played major part in TCE removal. Scavenging tests and ESR spectroscopy confirmed the dominant role of O 2 •– and 1 O 2 in TCE degradation. The stability and viability of 6%Ca-Fe 2 O 3 and 5%Cu-Fe 2 O 3 catalysts were evaluated by repetition tests and in the presence of surfactants, TCE removal in real water matrix, and in the degradation of multi-pollutants.
✓ 已验证
产品关联
DOI
高影响因子
Advanced Energy Materials
·
2022
·Vol. 12
·期 22
·2200392
·
IF 29.698
Peng Zhong,Kazuaki Toyoura,Lulu Jiang,Lubing Chen,Sara Adeeba Ismail,Naoyuki Hatada,Truls Norby,Donglin Han
A significant hydration and protonic conduction in La 2 NiO 4+ δ -based Ruddlesden–Popper (RP) oxides will enable their use as positrode materials in proton ceramic electrochemical cells (PCECs). Unlike perovskite electrolytes and positrode materials, where protons reside and jump on regular oxide ions, RP oxides such as La 2 NiO 4+ δ may contain oxygen interstitials and offer the possibility that protons locate on and migrate by help of these, suggesting a mechanism by which positrodes may operate by triple conduction. Here, theoretical calculations that support proton migration between interstitial oxide ions in the rock-salt layer via unshared oxide ions in the perovskite layer are reported. Furthermore, water contents of pristine La 2 NiO 4+ δ and La 2- x A x NiO 4+ δ ( A = Ca, Sr, Ba) are reported, showing that hydration increases with the level and basicity of the dopant. Hebb-Wagner blocking electrode measurements show significant partial protonic conductivity in all samples. The effects of doping on hydration and of p H 2 O on the p-type conductivity suggest that protons reside primarily on structural oxide ion, but a role of interstitial oxide ions for dissolution and migration of protons cannot be ruled out in cases with oxygen excess. The results are instructive for further studies and optimization of RP oxides as potential positrode materials for PCECs.
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 29
·期 4
·6375-6388
·
IF 4.223
Ahmad Khalil,Shah Izaz Ali,Ali Sharafat,Khan Muhammad Tariq,Qureshi Muhammad Bilal Ahmed,Shah Syed Hassan Ali,Ali Asmat,Rashid Wajid,Gul Hifza Nayab
Ferric hydrate has been extensively applied for the removal of various types of pollutants from wastewater because of its low cost and high efficiency. However, its wide-scale application has been greatly restricted by high-dose and low-adsorption capacity. Therefore, a novel Ca-doped ferrihydrite adsorbent has been synthesized and used for the enhanced removal of fluoride from wastewater in the presence of other co-existing ions. At 5 mg/L initial fluoride concentration and pH 5, the removal efficiency of fluoride approached to 97.5% and remained stable. Similarly, with the increase of dose from 100 to 300 mg/L, the fluoride removal linearly increased to 98% and remained plateau at neutral pH. Also, the presence of co-existing ions such as NO 3 − , SO 4 2− , Cl − , and natural organic matter has not significantly influenced the removal performance of the adsorbent. Fluoride removal best fit the pseudo-second-order reaction kinetics and Langmuir isotherm model. The prepared adsorbent exhibited a maximum adsorption capacity of 53.21 mg/g for fluoride uptake from water. The SEM-EDX confirmed the doping of Ca onto the ferrihydrite where the elemental peaks of Ca and Fe emerged at the energy value of about 3.6 Kev and 7.1 Kev respectively in EDX analysis. In addition, SEM results of Ca-doped ferrihydrite adsorbent illustrated that a large microplates type of products was acquired after synthesis. The regeneration results confirmed that adsorbent could retain their original adsorption capacity after five regeneration cycles. The current study suggested that Ca-doped ferrihydrite has the application potential for the enhanced adsorption of fluoride from the water phase. Graphical abstract
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Shuo Yan,Yun Li,Jilin Cao
The calcium nitrate (Ca(NO 3 ) 2 ) waste generated from the production of nitrophosphate fertilizers brings about serious environment and human health issues. Using Ca(NO 3 ) 2 waste and ammonium bicarbonate (NH 4 HCO 3 ) fertilizer as raw materials, higher-value spherical calcite mesocrystals have been synthesized via precipitation method. The synthesis conditions are optimized from the aspects of dispersant, crystal control agent and reaction temperature, and the mechanism that regulates the size and morphology of calcite is illustrated. The synthesized spherical calcite mesocrystals exhibit the small particle size of ca. 5 µm and high specific surface area of 84.44 m 2 /g. Under the dispersion effect of polyvinylpyrrolidone, the adsorption of crystal control agent citric acid on the calcite particles results in the formation of the spherical mesocrystal morphology. The yield of calcite in this process could reach 94.3%. Ca 2+ ion remaining in the mother liquor are further removed in the form of CaCO 3 by addition of calcium oxide , and a mixture of ammonium nitrate and a small amount of NH 4 HCO 3 is obtained by concentrating the filtrate, which can be used as nitrogen fertilizers. This work provides a new insight into the low-cost synthesis of spherical calcite mesocrystals with the high specific surface area and the comprehensive utilization of Ca(NO 3 ) 2 waste.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2021
·Vol. 328
·期 3
·1019-1032
·
IF 1.371
Wang Yugang,Zhang Weimin,Chen Jiahong,Guo Yadan
A new type of Ca/Fe-phosphate composite CFP(CN) was prepared by a sol–gel method. The effects of pH, reaction time, initial uranium concentration, reaction temperature, and Mn(II) selective adsorption were investigated by static batch experiments. The adsorption process of CFP(CN) on U(VI) was in line with the quasi-second-order kinetic model and the Langmuir adsorption isotherm model. The results of thermodynamic analysis show that the adsorption of U(VI) by CFP(CN) is a spontaneous process with heat absorption and entropy increase. The adsorption mechanism of U(VI) on CFP(CN) was investigated by SEM, XRD and FT-IR.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Yongjun Sun,Shengbao Zhou,Wenquan Sun,Sichen Zhu,Huaili Zheng
In order to effectively remove the dissolved heavy metals and the heavy metals on the colloidal particles during the flocculation process, a novel dual-functional chitosan flocculant CMCTS-g-P(AM-CA) is prepared by ultraviolet light-initiated graft polymerization using CMCTS, AM, and ammonium dithiocarbamate. The main influencing factors of monomer concentration, monomer ratio, pH value, photoinitiator concentration, and illumination time are investigated on the basis of intrinsic viscosity, grafting rate, and grafting efficiency of CMCTS-g-P(AM-CA). Characterization results provided empirical evidence for existence of chelating groups. In addition, CMCTS-g-P(AM-CA) was applied to treat the simulated heavy metals and electroplating wastewater. The effect of CMCTS-g-P(AM-CA) dosage, pH value, and reaction G value on flocculation efficiency was also explored. After the two-stage flocculation, the residual concentration of Ni(II), COD, and turbidity of actual electroplating wastewater decreased to 0.96 mg/L, 93.00 mg/L, and 1.71 NTU after flocculation tests at optimal condition, respectively. Finally, the “3E” triangular evaluation model is established and applied to evaluate the flocculation performance of CMCTS-g-P(AM-CA) on the actual heavy metal wastewater further, thereby proving its excellent chelation flocculation performance.
✓ 已验证
产品关联
DOI
高影响因子
Arabian Journal of Chemistry
·
2023
·
IF 6
Fulong Cheng,Yinian Wang,Yuting Fan,Dan Huang,Jie Pan,Wei Li
Biochar-based adsorbents for phosphate removal from wastewater has gained increasing attention and achieved significant progress. However, there is still much room for the enhancement on adsorption performance in terms of removal rate, adsorption capacity and pH application range. Herein, novel Ca-Al-La modified biochar adsorbents in this study were synthesized for enhancing phosphate adsorption in wastewater. The synthesis parameters of adsorbents were optimized by using the response surface methodology (RSM). The Ca-Al-La modified biochar adsorbent synthesized under the optimal conditions (CAL-MBC) exhibited superior adsorption capability towards phosphate. Specifically, CAL-MBC achieved a rapid removal rate to reach the adsorption equilibrium within 1 h, a maximum phosphate adsorption capacity of 152.9 mg/g, and excellent pH stability within a broad pH range of 3.0–11.0. The adsorption mechanisms involving electrostatic interaction, precipitation and inner-sphere complexation via ligand exchange were responsible for the excellent adsorption performance of phosphate on CAL-MBC. This study verifies CAL-MBC as a promising metal modified biochar adsorbent to enhance phosphate removal from wastewater.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2026
·
IF 7.1
Min Li,Jiang Wang,Feiyu Liu,Xinze Song,Chunmei Su,Jinjia Liu,Shuai Wang,Jingchun Jia,Hongwei Ji,Chuncheng Chen
Fluoride contamination in groundwater and the disposal of spent adsorbents remain critical environmental challenges. Herein, a series of monolithic Ca-containing MgAl layered double hydroxide/polyacrylonitrile nanofiber membranes (Mg 2-x Ca x Al-LDH/PAN) were fabricated via electrospinning, which combine the high adsorption performance of LDH with the exceptional separability of nanofibrous matrices. Mg 1.9 Ca 0.1 Al-LDH/PAN showed 96.2% removal efficiency for 10 mg/L F - and maximum adsorption capacity of 16.7 mg/g at 25 °C in a batch reactor, and achieved a specific treatment rate of 150 L/kg/h in a fixed-bed column. The adsorption mechanisms were elucidated through combined experimental and DFT studies. More importantly, rather than following conventional regeneration routes, the spent fluoride-laden adsorbent was converted through pyrolysis into a fluorine-doped carbon-based electrode material. This upcycled material retained a high-surface-area fibrous structure and exhibited enhanced oxygen reduction reaction (ORR) activity compared to its non-fluorinated counterpart. This work presents an “adsorb-and-transform” paradigm that integrates efficient water decontamination with sustainable recovery of functional materials for energy applications. Download: Download high-res image (184KB) Download: Download full-size image
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 42
·19726-19736
·
IF 3.3
Xingxin Xu,Hualiang Huang
In this work, Ca(H2PO4)2 was used as a green corrosion inhibitor for AZ91D magnesium alloy in 3.5 wt% NaCl solution. The corrosion inhibition behavior and mechanism were analyzed using electrochemical tests, high-definition video measuring microscopy, scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The electrochemical testing results showed that the optimal corrosion inhibition concentration of Ca(H2PO4)2 was 0.6 g L−1, and the highest corrosion inhibition efficiency was 89.29% after 48 h immersion in the corrosive medium. Optical microscopy and SEM images showed that an obvious protective film formed on the Mg alloy surface in solution inhibited with Ca(H2PO4)2. EDS and XRD results showed that the protective layer was composed of Mg(OH)2 + MgHPO4 + Ca3PO4, and MgHPO4 played a major role. The precipitation mechanism of Ca(H2PO4)2 as a corrosion inhibitor was proposed.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
S.J. Guo,X.K. Tian,Y.X. Xu,J. Yan,S.H. Ju,C.Y. Zhao
Thermochemical energy storage (TCES) is a promising technology to overcome solar intermittency and volatility. However, weak solar absorption, poor cyclic stability for calcium carbonates , and cost issues for metal oxides hinder the applicability of these materials for thermochemical energy storage. Herein, an advanced, affordable, and effective TCES system is proposed, and the corresponding calcium carbonate-metal oxide synergistic material is designed with improved solar absorption and cyclic stability. The optimum molar ratio is Ca:Co:Mn:Mg = 100:20:7.5:5 for the synergistic material fabricated by the modified sol–gel method, where Ca element plays the primary role in heat storage, Co element serves as the primary optical performance enhancer and secondary heat storage component, and Mn/Mg elements act as the secondary performance modifiers. The solar absorptivity is boosted to ∼ 79.3%, and the heat storage density is 1295 kJ/kg after 30 high-temperature cycles, which are 6 times and 2.2 times higher than those of commercial calcium carbonate, respectively. Homogeneous mixing of modifiers at the microscale and stable, well-developed pore structure are critical factors for cyclic stability enhancement. The change of electronic structure on the Fermi level caused by Co/Mn ion doping is the key to optical absorption improvement, and the promoting amplitude exhibits wavelength dependence. This work expands the limited list of currently available TCES materials and the comprehensive description of optical properties offers guidance for future implementation of TCES materials with high solar absorption in specific wavelengths.
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Donglin He,Changlei Qin,Zonghao Zhang,Shuai Pi,Jingyu Ran,Ge Pu
The control of anthropogenic CO2 emissions has attracted worldwide attention because of global warming. Among diverse carbon capture technologies, calcium looping (CaL) is proposed as a favorable approach for postcombustion CO2 mitigation. However, the sorbents’ capacitive loss with increased CaL cycling has severely limited the efficient application of the method. Therefore, obtaining sintering-resistant Ca-based sorbents with high capture capacity, fast capture kinetics, and superior stability is considered a research priority. Here, we reported our latest work on the development of a novel Y2O3/MxOy-modified Ca-based sorbent with superior CO2 sorption performance. Y20/Mg20, i.e., synthetic Ca-based sorbents with Y and Mg incorporated at the mass ratio of 1:1, achieved a significantly high conversion (above 90%) in 20 CaL cycles at a typical calcination temperature (∼900 °C) and was stabilized at the CO2 uptake of 0.311 g of CO2/g of sorbent even after 122 CaL cycles. A comprehensive investigation revealed that the outstanding performance arose from the characteristics of (1) superior surface area and pore volume, provided by pores with radii of <20 nm, (2) a gradually formed skeleton-type structure, and (3) a porous internal structure with a homogeneous distribution of Y2O3 and MgO nanoparticles.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）