Preparation of lithium-doped NaV6O15 thin film cathodes with high cycling performance in SIBs

Xu Hai-Yan,Ruan Jun Hai,Liu Fang Lin,Li Dong-Cai,Zhang Feng-Jun,Wang Ai-Guo,Sun Dao-Sheng,오원춘 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.3

Lithium ions-doped NaV6O15 thin films have been prepared using a simple low temperature liquid phase deposition method and subsequent annealing process. X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), scanning elec- tron microscopy (SEM), and photoelectron spectroscopy (XPS) have been used to study the structural and physicochemical characteristics of the NaV6O15 film. The films were grown on the FTO conductive glass and used directly as an electrode of sodium ion batteries. The prepared lithium ions-doped NaV6O15 thin film electrodes showed an excellent cycling stability and discharge capacity, which may be attributed to the stability of the Li+ embedded into the gap between the V–O layers to maintain the structure and its stable β-phase structure transformed after the first cycle. The cycling stability greatly improved with increasing annealing temperature, while the discharge capacity decreased. The capacities of the film electrodes annealed at 400 °C and 450 °C maintained above 97% after 100 cycles. The lithium-doped NaV6O15 underwent a phase transition dur- ing the first charge/discharge cycle. The new transformed phase has perfect crystal structure stability undergoing insertion and deinsertion of Na+. Therefore, the lithium-doped NaV6O15 thin film possesses good cycling stability and is expected to be a promising thin film cathode for sodium-ion batteries.

A liquid phase deposited porous flower-like HNaV6O16⋅4H2O film developed for a novel adsorbent to remove Pb2+, Cu2+, Mn2+ and Cd2+

Xu Hai-Yan,Yang Yi Cai,Li Dong-Cai,Wu Ran Ran,Wang Ai-Guo,Sun Dao-Sheng,Zhang Feng-Jun,오원춘 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.3

Heavy metal ion pollution of water resources is becoming increasingly serious, and adsorption is one of the most effective strategies for removing heavy metal ions. In the paper, hydrated hydrogen sodium vanadium oxide (HNaV 6O164H2O) fi lm developed for heavy metal ion adsorption was prepared directly via a low-temperature liquid-phase deposition approach. The prepared film shows an interesting porous flower-like morphology and has large spacing ( d = 10.87 Å). The highest adsorption capacity of the obtained HNaV 6O164H2O fi lm for Pb 2+, Cu 2+, Cd 2+ and Mn 2+ is 513 mg/g (2565 mg/m 2), 430 mg/g (2150 mg/m 2), 134 mg/g (875 mg/m 2) and 175 mg/g (670 mg/m 2), respectively. The adsorption percentage of the sample decreased from 92.2 to 86.3% after 4 cycles. The adsorption process follows the Langmuir adsorption isotherm and the pseudo second-order dynamic model, indicating that heavy metal ion adsorption by the fi lm is a single molecular layer chemical adsorption. In combination with various characterizations and comparison tests of samples after adsorption, the adsorption mechanisms include surface electrostatic attraction, complexation, and cation exchange. The results indicate that the fi lm is a potential material to remove heavy metal ions from the aqueous solution.

Crack‑free TiO2 films prepared by adjusting processing parameters via liquid phase deposition technique

Jie Li,Hai‑Yan Xu,Ai‑Guo Wang,Feng‑Jun Zhang,Dao‑Sheng Sun,Won‑Chun Oh 한국세라믹학회 2020 한국세라믹학회지 Vol.57 No.2

TiO2 thin films with controllable morphology and grain size were prepared via a liquid phase deposition (LPD) technique. The effects of the processing parameters including the ( NH4)2TiF6 concentration, solution pH, and ( NH4)2TiF6:H3BO3 molar ratio on the grain size and morphology of the films were investigated. The prepared samples were characterized by X-ray diffraction, scanning electron microscopy, and ultraviolet–visible spectroscopy. The results showed that the deposition parameters significantly affected the growth and nucleation velocities of the crystalline grains, which resulted in the formation of TiO2 films with different morphologies and grain sizes. The capillary stress among the grains of the film, which resulted in the cracking of the film, depended on the size of the grains. Thus, the cracking of the LPD-derived TiO2 films could be mitigated by adjusting the deposition parameters.

Ginseng consumption and risk of cancer: A meta-analysis

Jin, Xin,Che, Dao-biao,Zhang, Zhen-hai,Yan, Hong-mei,Jia, Zeng-yong,Jia, Xiao-bin The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.3

Background: The findings of currently available studies are not consistent with regard to the association between the risk of cancer and ginseng consumption. Therefore, we aimed to evaluate this association by conducting a meta-analysis of different studies. Methods: To systematically evaluate the effect of ginseng consumption on cancer incidence, six databases were searched, including PubMed, Ovid Technologies, Embase, The Cochrane Library, China National Knowledge Infrastructure, and Chinese VIP Information, from 1990 to 2014. Statistical analyses based on the protocol employed for a systematic review were conducted to calculate the summary relative risks (RRs) and 95% confidence intervals (CIs). Results: We identified nine studies, including five cohort studies, three case-control studies, and one randomized controlled trial, evaluating the association between ginseng consumption and cancer risk; these studies involved 7,436 cases and 334,544 participants. The data from the meta-analysis indicated a significant 16% lower risk of developing cancer in patients who consumed ginseng (RR = 0.84, 95% CI = 0.76-0.92), with evidence of heterogeneity (p = 0.0007, $I^2$ = 70%). Stratified analyses suggested that the significant heterogeneity may result from the incidence data for gastric cancer that were included in this study. Publication bias also showed the same result as the stratified analyses. In addition, subgroup analyses for four specific types of cancer (colorectal cancer, lung cancer, gastric cancer, and liver cancer) were also performed. The summary RRs for ginseng intake versus no ginseng consumption were 0.77 for lung cancer, 0.83 for gastric cancer, 0.81 for liver cancer, and 0.77 for colorectal cancer. Conclusion: The findings of this meta-analysis indicated that ginseng consumption is associated with a significantly decreased risk of cancer and that the effect is not organ specific.

Effects of Nutrient Levels on Cell Growth and Secondary Carotenoids Formation in the Freshwater Green Alga, Chlorococcum sp.

Liu, Bei Hui,Dao Hai Zhang,Lee, Yuan Kun 한국미생물 · 생명공학회 2000 Journal of microbiology and biotechnology Vol.10 No.2

The freshwater green alga Chlorococcum sp. grew on NH_4^+, NO_3^-, urea, yeast extract, and peptone as the nitrogen source showing similar patterns of growth and secondary carotenoid (SC) production. However, the most suitable nitrogen source for the induction of SC was urea. The effects of nutrient levels (urea, phosphate, sulfate, ferrous iron, and salt) on growth and SC production were studied by varying the concentration of each nutrient in batch cultures. High biomass production was achieved in cultures containing 20- 28mM urea, 4.8-10mM phosphate, 1.6mM sulfate, 70mM NaCl, and 20-100μM iron. The highest SC content in biomass was obtained when cultured at 5-10mM urea, 12mM phosphate, 1.6mM sulfate, 170mM NaCl, and 50μM iron. The optimum concentrations of nutrients for biomass and for the SC accumulation in biomass were evaluated and the two media for achieving high biomass production and SC production were thus developed. The extent to which each parameter to stimulate the formation of SC in the alga were varied and the potentially improved SC production by manipulating the nutrient levels in the modified media were discussed.

Preparation of porous cordierite ceramic with acid-leached coal gangue

Wang Xu-Dong,Xu Hai-Yan,Zhang Feng-Jun,Li Dong-Cai,Wang Ai-Guo,Sun Dao-Sheng,오원춘 한국세라믹학회 2020 한국세라믹학회지 Vol.57 No.4

The eff ect of impurities in coal gangue on the sintering and properties (porosity and compressive strength) of porous cordierite ceramics has been investigated by adjusting the amount of impurities by controlling the acid–gangue ratio during acid leaching. The sintering behavior and microstructure of the porous ceramics have been characterized via X-ray diff ractometry and scanning electron microscopy. The eff ects of both the acid–gangue ratio and sintering temperature on the porosity and compressive strength have been also investigated. The results indicated that both porosity and compressive strength of the porous cordierite ceramics prepared using acid-leached coal gangue were evidently improved. The content of the impurities in coal gangue was adjusted via acid leaching by controlling the acid–gangue ratio. The appropriate content of impurities in coal gangue facilitated the sintering process and improved the porosity and compressive strength of the obtained porous cordierite ceramics.