SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
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IF 8.1
Yuanqiong Mu,Mei Zhang,Min Guo
Lithium silicate (Li 4 SiO 4 ) sorbent has garnered attention in CO 2 capture due to its high theoretical adsorption capacity and fast kinetics. However, its adsorption capacity and kinetics were hindered by low CO 2 concentration. Improving adsorption performance of Li 4 SiO 4 at low CO 2 concentration has become the key to industrial application. In this work, high-activity Na-doped Li 4 SiO 4 with controllable active substance Li 3 NaSiO 4 was achieved. The influences of raw materials ratios on the CO 2 adsorption performance were systematically investigated. When R Li/Si =4.05:1 and R Na/Si =0.15:1, the sample exhibited the highest adsorption capacity of 32.28 wt% with an equilibrium time of 29 min, and a superior stable capacity of 31.09 wt% in 15 cycles. Importantly, the double exponential fitting revealed that LiNaCO 3 accelerated the ion diffusion rate and real-time adsorption processes showed Li 3 NaSiO 4 expedited surface chemical reaction rate. Based on these, a novel Na 2 CO 3 eutectic doping mechanism was proposed. The active substance Li 3 NaSiO 4 , generated through Na doping, along with its product formed from the reaction with CO 2 , molten LiNaCO 3 , acted synergistically to improve adsorption performance by accelerating surface chemical reaction rate and ion diffusion rate. Compared with other doped Li 4 SiO 4 , the sorbent prepared in this work demonstrated competitive adsorption performance, providing theoretical and technical support for the large-scale production of high-activity Li 4 SiO 4 .
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2025
·
IF 4.5
Wujie Ge,Yuanxiang Fu,Chaonan Wang,Lirong Yan,Qi Feng,Bing Yan,Xiang Li
The high-nickel cathode material LiNi 0.865 Co 0.095 Al 0.04 O 2 (NCA) has garnered significant attention due to its high energy density and cost-effectiveness in production. However, this material is also prone to rapid capacity degradation, primarily due to phase transitions occurring during the redox process. In this paper, the co-modification with Na and B cations is employed to stabilize the lattice structure and enhance the electrochemical performance of the NCA material. It can be found that the incorporation of Na and B cations in the lattice can reduce cation mixing, expand the Li-layer spacing and improve crystal stability, thereby increasing the specific capacity and cyclic stability of the NCA material. Specifically, the co-doped NCA-2 sample exhibits a specific capacity of 202.1 mAh/g at 0.1 C and maintains a capacity retention of 78.75 % at 1 C after 300 cycles, representing a substantial improvement over the pristine material (187.2 mAh/g and 61.68 % capacity retention). Moreover, at a current density of 10 C, the co-doped NCA-2 sample demonstrates a high specific capacity of 133.9 mAh/g, compared to 110.1 mAh/g for the pristine material. The Na/B co-doping strategy presented in this study offers a straightforward method to improve the cyclability and rate behavior of cathode materials, highlighting its potential for commercial applications.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2019
·
IF 5.162
Biwen Duan,Linbao Guo,Qing Yu,Jiangjian Shi,Huijue Wu,Yanhong Luo,Dongmei Li,Sixin Wu,Zhi Zheng,Qingbo Meng
In CZTSSe solar cells, a simple sodium-incorporation post-treatment method toward solution-processed Cu 2 ZnSnS 4 precursor films is presented in this work. An ultrathin NaCl film is deposited on Cu 2 ZnSnS 4 precursor films by spin-coating NaCl solution. In subsequent selenization process, the introduction of NaCl is found to be benefacial for the formation of Cu 2- x Se, which can further facilitate the element transportation, leading to dense and smooth CZTSSe films with large grains and less impurity Cu 2 Sn(S,Se) 3 phase. SIMS depth profiles confirm the gradient distribution of the sodium element in Na-doped absorbers. Photoluminescence spectra show that the introduction of appropriate sodium into the absorber can inhibit the band tail states. As high as 11.18% of power conversion efficiency (PCE) is achieved for the device treated with 5 mg mL −1 NaCl solution, and an average efficiency of Na-doped devices is 10.71%, 13% higher than that of the control groups (9.45%). Besides, the depletion width and the charge recombination lifetime can also have regular variation with sodium treatment. This work offers an easy modification method for high-quality Na-doped CZTSSe films and high-performance devices, in the meantime, it can also help to further understand the effects of sodium in CZTSSe solar cells.
研究领域:
材料科学
·
太阳能电池技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2019
·
IF 7.467
Tongtong Yao,Nianjun Hou,Juanjuan Gan,Jun Wang,Xiaojing Zhi,Lijun Fan,Tian Gan,Yicheng Zhao,Yongdan Li
Sr 2-x Na x FeMo 0.65 Ni 0.35 O 6-δ is synthesized as an anode material for solid oxide fuel cells. The effects of Na on the crystalline phase and electrical properties are investigated. The main perovskite phase changes into a Ruddlesden-Popper structure after reduction when x is less than 0.1, while the material with a higher amount of Na keeps the perovskite structure. FeNi x alloy nanoparticles are exsolved during reduction, in which the content of Ni increases with the rise of Na amount. The surface oxygen vacancy concentration is also influenced by the doping of Na, and the highest value is reached when x is 0.1. Sr 1.9 Na 0.1 FeMo 0.65 Ni 0.35 O 6-δ anode exhibits the highest activity, and a single cell supported by a 300-μm-thick La 0.8 Sr 0.2 Ga 0.8 Mg 0.2 O 3-δ electrolyte layer shows maximum power densities of 1495 and 627 mW cm −2 at 850 °C with H 2 and wet CH 4 as fuels, respectively. The coking resistance of the anode is also improved with Na doping.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
SOLID STATE IONICS
·
2024
·
IF 3
Jiatai Wang,Yan Wang,Shunli Hou,Geng Zhou,Yuanyuan Li,Xiaocen Yan,Changjuan Deng,Xiaoyi Hou,Jian Li
Lithium-ion batteries (LIBs) as energy storage devices have been booming recently to fill the demand for energy requirements. High‑nickel ternary cathode material LiNi 0.815 Co 0.15 Al 0.035 O 2 (NCA), extremely possible to be the next generation of cathode materials for applications due to its high energy density , low cost, and environmental friendliness. However, the rate capability and cycling stability of this cathode material is mediocre. In this work, NCA-based cathode materials have been modified by sodium (Na + ) doping through a high-temperature solid-state reaction, the results show that Na + -doping can effectively improve the electrochemical performance of NCA. Electrochemical test results show that Na + -doping improves Li + diffusion coefficient , inhibits NCA polarization, and reduces the charge transfer impedance. As-prepared 2%Na-NCA at the current density of 1.0C shows a discharge-specific capacity of 149.16 mAh/g and a retention rate of 96.49% after 100 cycles, but the retention rate of the Pure-NCA was (84.47%). Furthermore, 2% Na-NCA shows 121.07 mAh/g at 5.0C, with an increase of 27.05 mAh/g over the Pure-NCA (94.02 mAh/g). The results of the study showed that doping with sodium ions can effectively improve the rate capabilities and cycling stability of NCA.
研究领域:
材料科学
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能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
·
IF 12.2
Bo Ran,Ping Hu,Jun Sun,Jialu Fang,Qihua Sun,Juqi Wang,Yuqing Zhu,Ning Tian,Zhaofeng Wu,Haiming Duan
In this study, biomass-derived carbon material obtained from Lyocell fibers was first utilized as a gas sensor. The impacts of varying pyrolytic carbonization temperatures and pregrinding treatments on the structure, surface morphology, elemental composition, and gas sensitivity of the samples were thoroughly examined. The CL-500 sensor can realize rapid detection of trimethylamine with a high response (12.79k%, 500 ppm) and high selectivity at room temperature; the response/recovery times are 10 s and 2 s, respectively, and the theoretical detection limit is 3.96 ppm. Moreover, after four months, the response of the CL-500 sensor to trimethylamine fluctuated by less than 9.7 % compared with that of the fresh sensor, indicating good stability. It also shows good recovery after seven consecutive response-recovery cycles. Additionally, the CL-500 sensor has promising applications in real-life fish freshness monitoring. Theoretical calculations indicate that the introduction of trace amounts of Na enhances the sensing performance of this sensor for target gases. This study serves as a guide for developing cost-effective, high-performance gas sensors, promoting the efficient and high-value utilization of biomass waste.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Yuanqiong Mu,Junkai Chong,Xuehua Shen,Mei Zhang,Zuotai Zhang,Min Guo
Lithium silicate (Li 4 SiO 4 ) adsorbents garnered considerable interest for CO 2 capture due to their high adsorption capacity and stable cycling performance. While Na 2 CO 3 doping has been shown to enhance its the adsorption capacity at low CO 2 concentrations, the resulting samples exhibited poor cycling stability. Previous research has predominantly focused on the adsorption process, often overlooking the desorption kinetics. This study addressed this gap by investigating the desorption kinetics and decay mechanisms of Na-doped Li 4 SiO 4 to develop a version with long-term cycling stability from fly ash. The Na/Si ratio and desorption conditions were optimized. Optimal cycling stability was achieved at R Na/Si = 0.25 and a desorption temperature of 700 °C, yielding an initial adsorption capacity of 29.45 wt% and retaining 83 % of this capacity after 56 cycles. Phase analysis, desorption kinetics modeling, and examination of kinetic parameter evolution over multiple cycles uncovered the decay mechanisms in Na-doped Li 4 SiO 4 . Active phase Li 3 NaSiO 4 ′s poor reversibility contributed to performance degradation. Furthermore, molten LiNaCO 3 played a dual role during desorption: it accelerated the diffusion of Li + /Na + /CO 3 2– but hindered CO 2 diffusion. When the LiNaCO 3 content was low, the diffusion of Li + /Na + /CO 3 2– became the rate-limiting step; conversely, when the content was high, its reaction with CO 2 to form C 2 O 5 2- impeded diffusion, thus becoming the new rate-limiting step.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Haotian Liu,Kui Liu,Da Huang,Qin Yu,Cheng Liu,Jie Li,Yulong Liao,Dainan Zhang,Huaiwu Zhang
Herein, the dielectric properties of Na + doped Li 10 ZnTi 13 O 32 ceramics were investigated by first-principles computational prediction and combined with the solid-phase reaction method. Li 9.88 Na 0.12 ZnTi 13 O 32 obtained the best dielectric properties by sintering at 1050 °C for 4 h: ε r = 30.01, Q × f = 90,879 GHz (@7.8 GHz), τ f = 3.93 ppm/°C. In terms of extrinsic factors, the optimization of the densification, the creation of the second phase TiO 2, and the increase of the grain size resulted in better dielectric properties. Intrinsic factors indicate that the weakening of the damping behavior and the increase in the electron cloud density lead to a decrease in the dielectric loss. The increase in ion polarisation and the blue shift of the Raman wavenumber lead to a gradual increase in ε r . The temperature stability is optimized depending on the TiO 2 content. The optimized Li 9.88 Na 0.12 ZnTi 13 O 32 ceramics have unlimited applications in microwave communications.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Ke Wang,Chuanjiang Yang,Pengfei Zhao,Edward J. Anthony
The addition of molten Na 2 CO 3 can drastically accelerated the extremely slow sorption kinetics of Li 4 SiO 4 -based CO 2 sorbents in the sorption enhanced reforming process. However, the lack of a unified consensus about the effect of doped Na 2 CO 3 on the CO 2 capture process, now delays the development of more-effective Li 4 SiO 4 sorbents. Here, sorption tests, sturactural characterzations and periodic density functional theory calculations were combined to develop a better mechanistic understanding CO 2 sorption on Na-doped Li 4 SiO 4 . The Na-doped Li 4 SiO 4 exhibited a better CO 2 capture performance than pure Li 4 SiO 4 even below the melting point of any eutectic mixtures. Structural characterizations revealed that rather than generating physical favorable characteristics, the Na doping substituted at the Li site and created lithium–sodium orthosilicates (Li 4-x Na x SiO 4 ). Theoretical calculations agreeing with experimental results further demonstrated that Li 4-x Na x SiO 4 presented a weaker Na-O bond and generated more active phases (quasi Li 2 O groups) for larger sorption energies, more charge transfers and stronger CO 3 2– bond formation, in turn providing more reactive sites for enhanced CO 2 chemisorption as comparing with pure Li 4 SiO 4 . Finally, we propose a new and unified sorption mechanism independent of the traditional “melting layer” explanation.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2024
·Vol. 14
·期 13
·1118
·
IF 4.4
Na Guo,Lili Liu,Guilong Cao,Shurui Xing,Jingying Liang,Jianjun Chen,Zuojun Tan,Yuequn Shang,Hongwei Lei
Lead-free Cs3Cu2I5metal halides have garnered significant attention recently due to their non-toxic properties and deep-blue emission. However, their relatively low photoluminescence quantum efficiency and poor stability have limited their applications. In this work, sodium iodide (NaI) is used to facilitate the synthesis of Cs3Cu2I5nanocrystals (NCs), demonstrating improved photoluminescence intensity, photoluminescence quantum yield, and stability. Systematic optoelectronic characterizations confirm that Na+is successfully incorporated into the Cs3Cu2I5lattice without altering its crystal structure. The improved Photoluminescence Quantum Yield (PLQY) and stability are attributed to the strengthened chemical bonding, which effectively suppresses vacancy defects in the lattice. Additionally, light-emitting diodes (LEDs) based on 10% NaI-doped Cs3Cu2I5NCs were assembled, emitting vibrant blue light with a maximum radiant intensity of 82 lux and Commission Internationale de l’Eclairage (CIE) chromaticity coordinates of (0.15, 0.1). This work opens new possibilities for commercial lighting display applications.
研究领域:
材料科学
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光电技术
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Qian Dou,Jianhua Hou,Asif Hussain,Geshan Zhang,Yongcai Zhang,Min Luo,Xiaozhi Wang,Chuanbao Cao
Graphitic carbon nitride (g-C 3 N 4 ) is considered as a promising low-cost polymeric semiconductor as conjugated photocatalyst for energy and environmental application. This study exhibits a Na-doped g-C 3 N 4 with willow-leaf-shaped structure and high degree of crystallinity , which was synthesized with a convenient thermal polymerization using sodium carbonate (Na 2 CO 3 ) as the sodium source. The π-conjugated systems of g-C 3 N 4 were improved by doping sodium, which could accelerate the electron transport efficiency resulting in outstanding photocatalytic properties. Furthermore, optimum Na-doped g-C 3 N 4 (CN-0.05) attributed its enhanced irradiation efficiency of light energy to its narrower band gap and significant improvement in charge separation. Consequently, the H 2 evolution rate catalyzed with CN-0.05 can achieve 3559.8 μmol g −1 h −1 , which is about 1.9 times higher than that with pristine g-C 3 N 4 . The rate of CN-0.05 for reduction of CO 2 to CO (3.66 μmol g −1 h −1 ) is 6.6 times higher than that of pristine g-C 3 N 4 . In experiments of pollutants degradation, the reaction constants of degradation of rhodamine B (RhB) and methyl orange (MO) with CN-0.05 were 0.0271 and 0.0101 min −1 , respectively, which are 4.7 and 7.2 times more efficient than pristine g-C 3 N 4 , respectively. This work provides a simple preparation method for tailoring effective photocatalyst for the sustainable solution of environmental issues.
研究领域:
材料科学
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环境科学
·
能源科学
✓ 已验证
DOI
高影响因子
Small
·
2024
·
IF 13
Wentong Yang,Yixiong Ji,Wangxian Chen,Yining Pan,Zifei Chen,Shaoyang Wu,Salvy P. Russo,Yang Xu,Trevor A. Smith,Anthony Chesman,Paul Mulvaney,Fangyang Liu
Sodium (Na) doping is a well-established technique employed in chalcopyrite and kesterite solar cells. While various improvements can be achieved in crystalline quality, electrical properties, or defect passivation of the absorber materials by incorporating Na, a comprehensive demonstration of the desired Na distribution in CZTSSe is still lacking. Herein, a straightforward Na doping approach by dissolving NaCl into the CZTS precursor solution is proposed. It is demonstrated that a favorable Na ion distribution should comprise a precisely controlled Na + concentration at the front surface and an enhanced distribution within the bottom region of the absorber layer. These findings demonstrated that Na ions play several positive roles within the device, leading to an overall power conversion efficiency of 12.51%.
研究领域:
材料科学
·
可再生能源
·
光伏技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）