ACS Applied Energy Materials
·
2024
·
IF 5.4
Jiahao Xu,Kangwei Hou,Xiaolin Li,Yuhan Bian,Yaping Wang,Li Wang,Guangchuan Liang
The practical applications of lithium manganese iron phosphate (LMFP) are severely circumvented by the inferior electronic conductivity and electrochemical reaction kinetics. In this work, a Na+-doping method is adopted to prepare Li1–xNaxMn0.6Fe0.4PO4/C (x = 0, 0.01, 0.02, 0.03) materials by spray drying combined with the carbothermal reduction method. It is found that appropriate Na+ doping enhances the crystallinity, reduces Li–Fe antisite defects, decreases the primary particle size, and homogenizes the size distribution of the LMFP material. Moreover, the inferior rate and cycling performance of LMFP are mainly ascribed to the slower Li+ diffusion kinetics of Mn redox. A combination of experiments and DFT calculations shows that Na+ doping can increase the Li–O bond length, widen the Li+ diffusion channel, and decrease Li+ diffusion energy barriers, which can accelerate the Li+ diffusion rate and Mn redox kinetics, thereby improving the high-rate capability and cycling stability of Na+-doped samples. Besides, doped Na+ can not only act as pillars to stabilize the structure but also reduce Mn3+ content and Mn–Mn interactions to alleviate the Jahn–Teller effect, which also helps to improve the cycling performance of Na+-doped samples, wherein the Li0.98Na0.02Mn0.6Fe0.4PO4/C sample exhibits optimal rate and cycling performances. Its specific discharge capacity is 125.0 mAh g–1 at 5 C, and the capacity retention rate reaches 96.7% after 100 cycles at 1 C. Therefore, the Na+-doping strategy is believed to be an effective modification means to ameliorate the high-rate and cycling capabilities of olivine-based cathode materials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Lin-Pei Guo,Zhi-Yuan Guo,Jing Wang,Pan-Pan Zhang,Zhi-Hui Huang,Zhi-Yong Ji
Monovalent selective ion-exchange membranes have been widely used for lithium extraction from brine with a high Mg/Li ratio. However, extracting Li + directly from raw brine with high Na/Li ratio remains a significant challenge. This study introduces a flexible lithium selective composite membrane by incorporating lithium-ion conductor with a quaternized polymer. The lithium-ion conductor provides pathways for lithium transmission, while the quaternized polymer effectively hinders the leakage of impurity cations. As a result, with the applied voltage of 2.0 V, the membrane achieved a high Li + /Na + separation coefficient of 35.48 with a Li + flux of 8.33 × 10 −10 mol cm −2 s −1 in the simulated Yiliping brine, which are 56.3 and 2.8 times higher than that of commercial monovalent selective cation exchange membrane (CIMS). We proposed a lithium transport mechanism involving an adsorption-dehydration-diffusion process through the membrane. Theoretical calculations indicate that the combined effects of significant adsorption energy (−0.47 eV), low dehydration energy (515 kJ mol −1 ), and low diffusion barrier (0.37 eV) leads to the high selectivity for lithium. These findings provide promising prospects for the large-scale preparation of lithium ion-selective membranes, enabling the direct lithium extraction from raw brine.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Jia'nan Wang,Wenjun Huang,Haomiao Xu,Peng Cui,Zan Qu,Naiqiang Yan
Sulfur dioxide (SO 2 ), as a primary pollutant in the air, has attracted much attention due to the adverse effects on the atmospheric environment and human health. The wet flue gas desulfurization (WFGD) has been proved to be the most effective method to control the emission of SO 2 . However, the traditional absorbents in WFGD posed the problems of limited recycling utilization and susceptible to oxidation. In this study, we proposed the Na-Mg-Ci 3- compound system to repeatedly absorb SO 2 for rounds. The results demonstrated that the compound system can integrate the absorption capacity of Na 3 Ci absorbent and the regeneration efficiency of Mg 3 Ci 2 absorbent. We compared the performances of the compound systems with different alkaline earth metals (Li, Na, K), and the sodium was most suitable for the circulating desulfurization with the consideration of performance and economy. After that, we investigated the influence of ingredient proportions on the absorbent performance, and the results showed that the 0.4 mol/L Na 3 Ci and 0.2 mol/L Mg 3 Ci 2 were the best combination for the compound system in these experiments. In this condition, the compound system had the excellent effective sulfur capacity and regeneration speed in the recycling process. Moreover, the anti-oxidation effect of sodium ascorbate was explored, and the reusability performance of compound system can be improved with antioxidants. This study contributes to providing a novel method for the removal and recycling of SO 2 in the wet flue gas desulphurization.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Hailin Zhao,Bingjing Tang,Jie Tang,Yafeng Cai,Yao Cui,Hao Liu,Li Wang,Yunsong Wang,Wangcheng Zhan,Yanglong Guo,Yun Guo
Catalytic oxidation is believed to be the most efficient method for indoor formaldehyde purification. Herein, we reported that the Pt/Na-ZSM-5 catalyst with low Pt loading (0.16 wt %) prepared by depositing Pt on Na+ ion-exchanged ZSM-5 could completely oxidize 300 ppm formaldehyde in 2.5 vol % H2O at 32 °C and maintain its activity during the 62 h-long stability test. Multiple characterizations revealed that the presence of Na species significantly enhanced formaldehyde adsorption ability and made Pt species tend to exist in the form of metal Pt through electron transfer from Na to Pt, which promoted the activation of oxygen and opened a new efficient formaldehyde oxidation pathway, namely, direct decomposition of formate. The synergistic effects resulted in the TOF of Pt(0.16)/Na-ZSM-5 being about nine times higher than that of Pt(0.50)/ZSM-5. Our study showed that utilizing an alkali metal to tune the surface acidity/basicity of the support and the state of the supported noble metal was a promising way to improve the intrinsic catalytic performance and reduce noble metal usage.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2015
·
IF 5.636
Lu Li,Ping Li,Juan Fang,Qingling Li,Haibin Xiao,Hui Zhou,Bo Tang
Considering the important functions of cellular Na+ and K+ together with their cooperative efforts on various biological processes, it is significant to simultaneously detect Na+ and K+ at a single-cell level. Here, we present a novel method to discriminate and quantify simultaneously Na+ and K+ in single cells using a new near-infrared fluorescent probe associated with microchip electrophoresis. The fluorescent probe selectively responds to both Na+ and K+. The microchip electrophoresis allows accurate single-cell manipulation and effective distinction of Na+ and K+. Based on the method, the concentration of Na+ and K+ in single normal and cancer cells was compared, and the variation of Na+ and K+ in single cancer cells during the early stage of apoptotic volume decrease was monitored, which would help us to better understand the critical roles of Na+ and K+ in malignant cells and apoptosis. This method has paved a new way for the research of the synergistic function of Na+ and K+ in the regulation of various biological processes at a single-cell level.
研究领域:
分析化学
·
细胞生物学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Xin He,Wutong Chen,Feiyun Sun,Zekai Jiang,Bing Li,Xiao-yan Li,Lin Lin
Flow-electrode capacitive deionization (FCDI) is a promising electromembrane technology for wastewater treatment and materials recovery. In this study, we used low-cost Na-modified zeolite (Na-zeolite) to prepare a composite flow-electrode (FE) suspension with a small amount of highly conductive carbon black (CB) to remove and recover NH4+ from synthetic and actual wastewater (200 mg-N/L). Compared with conventional activated carbon (AC), the Na-zeolite electrode exhibited a 56.2–88.5% decrease in liquid-phase NH4+ concentration in the FE suspension due to its higher NH4+ adsorption capacity (6.0 vs. 0.2 mg-N/g). The resulting enhancement of NH4+ diffusion to the electrode chamber contributed to the improved performance of FCDI under both constant current (CC) and constant voltage (CV) conditions. The addition of CB to the FE suspension increased the conductivity and facilitated Na-zeolite charging for NH4+ electrosorption, especially in CV mode. NH4+-rich zeolite can be easily separated by sedimentation from CB in the FE suspension, producing a soil conditioner with a high N-fertilizer content suitable for soil improvement and agricultural applications. Overall, our study demonstrates that the novel Na-zeolite-based FCDI can be developed as an effective wastewater treatment technology for both NH4+ removal and recovery as a valuable fertilizer resource.
研究领域:
环境科学
·
水处理工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICS EXPRESS
·
2023
·Vol. 31
·期 15
·25298-25306
·
IF 3.8
Haoming Wei,Haoming Wei,Tingyu Si,Fan Xu,Wuyang Fan,Tengzhou Yang,Bingqiang Cao,Fangying Juan,Jun Xu,Yangqing Wu
Double perovskites without lead element have attracted great attention in recent years. Further increasing the photoluminescence quantum yield of lead-free double perovskites is necessary for their potential applications. In this work, Na+ doped Cs2SnI6 nanocrystals were synthesized by hot injection method. It was displayed that all the NCs have uniform hexagonal shape with good crystallization. Energy dispersing spectroscopy and X-ray photoelectron spectroscopy proves the Na+ ions were doped in the lattice of perovskite structure. The photoluminescence intensity of doped NCs is increased by 2.7-fold than that of pure NCs. A maximum photoluminescence quantum yield of 72% is obtained. The luminous mechanism was investigated by femtosecond transient absorption spectrum and a self-trap emission was proved by the observation of ground state bleaching and photo-induced absorption signals.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhe Xu,Xiao-Lei Shi,Yibo Zhang,Jisheng Liang,Meng Li,Chengyan Liu,Lei Miao,Siqi Liu,Shihao Wang,Qi Zhou,Jie Gao,Zhongwei Zhang,Wei-Di Liu,Ying Peng,Jun-Liang Chen,Zhi-Gang Chen
Owing to the non-toxicity and low cost, Mg 3 Sb 2 -based Zintls are promising candidates for mid-temperature thermoelectric applications. However, the thermoelectric performance of p-type Mg 3 Sb 2 is significantly lower than that of n-type ones. Here, we achieve simultaneous optimization of the band structure and enhanced phonon scattering through the combined doping of Na at the cation site and Bi at the anion site, leading to a competitive figure of merit, ZT of 0.73 at 773 K and a maximum theoretical energy conversion efficiency of 6.5 % at a temperature difference of 450 K. First-principles calculations indicate that Na and Bi co-doping effectively narrows the band gap and shifts the Fermi level into the valence band, thereby increasing the hole carrier concentration. This ensures a relatively high Seebeck coefficient and improved electrical conductivity, resulting in an excellent power factor of 7.5 µW cm −1 K −2 . Additionally, by adjusting the amount of Bi nanoprecipitates in the matrix, the heterogeneous interfaces significantly enhance phonon scattering and markedly reduce the lattice thermal conductivity (0.52 W m −1 K −1 ), collectively leading to the high thermoelectric performance. Furthermore, by pairing n-type Mg 3.18 Y 0.02 Sb 1.5 Bi 0.49 Se 0.01 , a double-leg thermoelectric device achieves an energy conversion efficiency of 4.1 % with a temperature difference of 390 K.
研究领域:
材料科学
·
热电材料
✓ 已验证
DOI
高影响因子
ENERGY
·
2022
·
IF 8.857
Haifeng Jiang,Haipeng Liu,Jiaxin Dong,Jiaxing Song,Sunhua Deng,Jie Chen,Yu Zhang,Wenpeng Hong
Using cellulose to produce high-quality oxygenated fuels or chemicals is becoming an important way to replace chemical synthesis technology. In this work, the Ce–Co–Na ternary composite metal catalyst is synthesized and used for catalytic cracking of cellulose to prepare the ketone-rich bio-oil production. To construct an environment-friendly process, CO 2 is used as a pyrolysis reaction atmosphere to improve the enrichment of ketones. Strong synergistic effects among metal components effectively promote the thermal-cracking of cellulose to produce primary products (anhydrosugars), and further convert to oxygenates due to the excellent oxygen transferability of the catalyst. The introduction of CO 2 enhances the selectivity of ketones in the liquid product, especially 2,3-dimethyl-2-cyclopenten-1-one. The highest content of ketones in the liquid is 22.73%, which is about four times higher than that of the blank sample. In addition, the generation of CO in the syngas is promoted. This study provides an alternative way for the pyrolysis of biomass to prepare ketone platform compounds and syngas production .
研究领域:
能源与燃料
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2018
·Vol. 6
·期 20
·5453-5461
·
IF 5.976
Shaohua Fan,Guojun Gao,Shiyu Sun,Sijun Fan,Hongtao Sun,Lili Hu
Absolute quantum efficiency (QE) of up-conversion (UC) materials is still limited to ∼3%, which strongly limits their applications in many areas. Herein, we report highly efficient UC β-NaYF4:Yb3+,Er3+ micro-cylinders prepared via a newly developed Li+/Na+ ion exchange method (IEM) with absolute QE as high as ∼4.0%. A small amount of Li+ is interstitially incorporated in β-NaYF4:Yb3+,Er3+, which not only maintains well the micro-cylindrical morphology but also enhances the emission intensity by ∼40%, doubles absolute UCQE (∼3.0% under a fixed excitation power density of 15 W cm−2), and prolongs the lifetime. The UC excitation profile is composed of a sharp peak at 976 nm and a weak shoulder at 935 nm. The absolute UCQE of Li+/Na+ IEM β-NaYF4:Yb3+,Er3+ is systemically studied over a wide excitation power density of 0.4–100 W cm−2, and we obtained impressively high UCQE of 4.0% under 60 W cm−2 power density, which is among the highest values in the literature. The application of two green UC emissions of Li+/Na+ IEM β-NaYF4:Yb3+,Er3+ in ratiometric thermometers is successfully demonstrated. The high relative temperature sensitivity (SR) of 1113/T2 and excellent repeatability as indicated by three heating–cooling cycles (293–753 K) suggest their promising application as a temperature sensor.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Materials Horizons
·
2023
·Vol. 10
·期 4
·1406-1415
·
IF 13.3
Shiling Jin,Renfu Li,Jiwen Zhu,Tao Pang,Tianmin Wu,Hongbing Zhan,Yuanhui Zheng,Feng Huang,Xueyuan Chen,Daqin Chen
Nonlinear multi-phonon (2–7) absorption in the Na+/Bi3+-alloyed Cs2AgInCl6 lead-free double perovskites with ∼100% photoluminescence quantum yield and superior stability is observed for the first time, which can be pumped by a femtosecond laser in a wide spectral range (800–2600 nm). First-principles calculations verify that the parity-forbidden transition from the valence band maximum and conduction band minimum (at the Γ point) is not broken by Na+/Bi3+ doping, and strong optical band-to-band absorption occurs at the L&X points. Time-resolved emission spectra evidence that single-photon and multi-photon pumping leads to the same self-trapped exciton transition and high-order nonlinear absorption will not induce a remarkable thermal effect. Finally, we demonstrate that the Cs2Na0.4Ag0.6In0.99Bi0.01Cl6 DP shows great potential for next-generation wavelength-selective and highly sensitive multiphoton imaging applications.
研究领域:
材料科学
·
光学
·
光子学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2023
·
IF 4.4
Xianju Zhou,Qianyang Chang,Guotao Xiang,Sha Jiang,Li Li,Xiao Tang,Faling Ling,Yongjie Wang,Jingfang Li,Zhen Wang,Xuecong Zhang
Light-emitting perovskite quantum dots (PeQDs) are extensively investigated owing to their evident merits. However, it is still a challenge to adjust their intrinsic emissions and enhance their thermal stability to achieve full-color highly emissive QD-based light-emitting diodes (QLEDs), especially blue QLEDs. Herein, we demonstrate an effective strategy to fundamentally stabilize the crystal structure of CsPbBr 3 QDs by codoping Na + and Cu 2+ ions, which are designed to substitute Cs + (A sites) and Pb 2+ (B sites), respectively. It is found out that the codoping metal ions have significantly improved the thermal stability and the optical properties of the QDs. 40% of the emission intensity can be remained after 8 thermal cycles (20–120 °C) for CsPbBr 3 : Na + /Cu 2+ QDs, whilst less than 10% is maintained for undoped CsPbBr 3 QDs. Accordingly, stable blue QLEDs are packed by CsPbBr 3 : Na + /Cu 2+ QDs. Strong electroluminescence with the maximum luminance of 7161 cd m −2 and low turn-on voltage of 2.4 V are realized. The CIE coordinates are tuned from green (0.10, 0.74) to blue (0.17, 0.25) via Na + and Cu 2+ codoping. The maximum external quantum efficiency (EQE max ) is obtained as 4.52% for PeLEDs based on codoped QDs. The proposed metal ions A and B sites dual substitution strategy guarantees PeQDs as an extremely promising prospect in potential applications as high-resolution displays and high-quality lightings.
研究领域:
材料科学
·
光电材料
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）