ENVIRONMENTAL TECHNOLOGY
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2020
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IF 2.213
Lihua Liu,Zhengchi Yang,Lu Zhao,Jinyan Liu,Xiong Liu,Jianrong Xue,Anping Tang
The adsorption characteristic and mechanism of poly(N1,N1,N3,N3-tetraallylpropane-1,3-diaminium chloride) (PTAPDAC) toward Cr(VI) ions were systematically investigated. Results showed that the removal efficiency of PTAPDAC toward Cr(VI) could reach above 98% at pH = 3–6. The equilibrium data of Cr(VI) adsorbed by PTAPDAC fitted the Langmuir model well, and the maximum sorption capacity deduced from the Langmuir model at 293 K was 273.17 mg g−1. The adsorption of PTAPDAC toward Cr(VI) was rapid and reached equilibrium within 60 min, and the adsorption kinetic process was relevant to the pseudo-second-order kinetic model. Moreover, the activation energy Ea was calculated as −22.505 kJ mol−1. The adsorption processes were spontaneous and exothermic driven by an increase in entropy, which involved electrostatic attraction, ion exchange, and redox reactions. The X-ray photoelectron spectroscopy analysis revealed that approximately 64.5% of Cr(VI) reduced to be Cr(III), and 24.29% of –C–NH+ deprotonated. The combination of reduced Cr(III) with tertiary amine groups resulted in a positively charged tertiary amine group, which further promoted Cr(VI) adsorption, thereby increasing the adsorption capacity of PTAPDAC toward Cr(VI). Therefore, PTAPDAC has a broad application prospect in removing Cr(VI) ions in wastewater.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
Advanced Energy Materials
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2023
·Vol. 13
·期 21
·2300529
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IF 27.8
Haobin Wang,Shuyi Huang,Haoze Kuang,Chi Zhang,Yulu Liu,Kaihang Zhang,Xinyu Cai,Xiaozhi Wang,Jikui Luo,Zhong Lin Wang
Triboelectrification for contacts between three types of materials—metals, polymers, and semiconductors—are investigated. The results show that triboelectrification is a charge exchange process between the surfaces of two friction materials, and its output is the synergetic effects of the electrostatic induction (ESI) and dynamic junction modulation (DJM). There are four current/voltage peaks in output of triboelectrification: two of them are attributed to the ESI effect and determined by the surface state densities and electron affinity difference of the materials, while the other two are associated with the DJM effect and determined by the charging exchange between the surface states and the depletion region. However, metals and polymers have no-modulation of depletion region due to their high conductivity and insulating nature, respectively, thus only two peaks induced by the ESI effect are observable no matter what types of metals and polymers are in pair for contacting. Semiconductors have a depletion region, there will be two more output current/voltage peaks induced by the junction modulation when a semiconductor is in contact with any type of materials. The observations reveal a universal triboelectrification mechanism for contacts between materials, and provide an intuitive guidance for the development of high-performance triboelectric nanogenerators.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2021
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IF 3.764
Xinyan Yang,Yunmei Wei,Yinhua Jiang,Yunyun Wang,Li Chen,Long Peng,Shen Zhang,Yan Yan,Yongsheng Yan
Removing excess phosphate from environmental water is extremely important to reduce eutrophication. In this study, cellulose nanocrystals (CNCs) were utilized as biological templates, and the SA-La-X was synthesized by calcination with lanthanum modification. Some characterization techniques were used to confirm the impregnation of La on the surface of mesoporous silica aerogel (SA). The obtained aerogels SA-La-5, 10, and 25 had large specific surface areas (262.69, 251.23, and 197.18 m2 g–1), and average pore sizes of aerogels SA-La-5, 10, and 25 were 5.14, 4.85, and 4.71 nm, respectively. The results manifested that sample SA-La-5 with the molar ratio of Si/La of 5:1 presented the maximum adsorption capacity of 42.08 mg g–1. Meanwhile, SA-La-X exhibited less La leaching, good stability, and strong selectivity for phosphate. Through the adsorption isotherm, the phosphate adsorption over SA-La-X samples followed the Langmuir model, and the kinetic experiment demonstrated that the adsorption process fitted the pseudo-second-order models. The phosphate adsorption mechanism of SA-La-X was detected by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD), and it was found that the binding mechanism of the adsorbent and phosphorus included electrostatic adsorption, surface precipitation, and ligand exchange. Among them, electrostatic and ligand exchange were considered to be the main ways to selectively adsorb phosphate at pH 3.0. At the same time, the prepared SA-La-X with a cylindrical shape was easy to separate without causing secondary pollution to the water system, which would be the promising adsorbent for phosphate adsorption in the water environment to reduce eutrophication.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
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IF 10.753
Ruofan Wu,Xu Zhai,Kuai Dai,Jiapan Lian,Liping Cheng,Gang Wang,Jiangzhou Li,Chuan Yang,Zhicheng Yin,Hongjuan Li,Xiaoe Yang
An acidified magnetic sludge-biochar (MSB) was prepared to enhance ammonium nitrogen (AN) removal efficiency in eutrophic water, and MSB was obtained by secondary pyrolysis of sludge biochar powder. A series of MSB were prepared under 300, 400, 500, 600 °C and different valence states of iron ions by impregnation pyrolysis , which is based on the deposition of unstable iron minerals on biochar matrix. Physicochemical properties of pristine biochar and MSB were revealed through characterization analysis, suggesting that MSB prepared by ferric chloride at 400 °C presented the largest adsorption capacity, and the acid-modification enhanced the ammonium adsorption capacity by 10.7%. Electrostatic attraction and ion-exchange processes were identified as the main adsorption mechanisms of MSB on AN. As the most dominant mechanism, ion exchange of AN with functional groups containing -OH and C O on the surface of MSB resulted in the relative content of -OH (61.3%) and C O (11.5%) bonds reduced to 34.2% and 7.0% respectively. The novel magnetic sludge-biochar with acid-modification possessed enhanced electron transfer capacity , revealing a removal pathway of ammonium by nitrification. The findings above demonstrated that MSB is a promising adsorbent for ammonium removal and can be applied to the natural nitrogen-rich water regulation.
研究领域:
环境科学
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水处理工程
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Tiantian Dai,Gang Meng,Zanhong Deng,Ying Chen,Hongyu Liu,Liang Li,Shimao Wang,Junqing Chang,Pengcheng Xu,Xinxin Li,Xiaodong Fang
As one of the bottleneck parameters for practical applications of metal oxide semiconductor-based gas sensors, sensitivity enhancement has attracted significant attention in the past few decades. In this work, alternative to conventional strategies for designing sensitive surfaces via morphology/defect/heterojunction control (then operating at an optimized isothermal temperature with a maximal response), a facile enhancement approach by decoupling surface charge exchange and resistance reading process (possessing different temperature-dependent behaviors) through pulsed temperature modulation (PTM) is reported. Substantially magnifying electrical responses of a generic metal oxide (e.g., WO3) micro-electromechanical systems sensor toward diverse analyte molecules are demonstrated. Under the optimal PTM condition, the response toward 10 ppm NO2 can be boosted from (isothermal) 99.7 to 842.7, and the response toward 100 ppm acetone is increased from (isothermal) 2.7 to 425, which are comparable to or even better than most of the state-of-the-art WO3-based sensors. In comparison to conventional (isothermal) operation, PTM allows to sequentially manipulate the physisorption/chemisorption of analyte molecules, generation of surface reactive oxygen species, and sensor resistance reading and thus provides additional opportunities in boosting the electrical response of oxide sensors for advanced health and/or environment monitoring in future.
研究领域:
材料科学
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环境监测
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产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
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2023
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IF 5.2
Moyu Liao,Xinli Yi,Zhongxu Dai,Hang Qin,Wenming Guo,Hanning Xiao
Three metal-organic frameworks including Ce-BDC, In-BDC and In/Ce-BDC and corresponding derived CuO/ZnO/In 2 O 3 /CeO 2 catalysts were prepared. The catalyst-loaded cordierite honeycomb ceramic supports were applied in a microreactor for hydrogen production via methanol steam reforming. The In/Ce-BDC-derived catalyst exhibited a methanol conversion rate of 100%, a hydrogen yield of 0.336 mol/h and an energy efficiency of 54% at 300 °C and an inlet methanol flow rate of 0.112 mol/h. Moreover, CO with content lower than 1.5% and catalytic stability of 30 h was recorded. The high specific surface area and superior redox property of the In/Ce-BDC-derived catalyst were characterized. The increased contents of oxygen vacancies and surface oxygen, in collaboration with the improved solid solubility of CuO and ZnO, were associated with the charge exchange induced by the strong interaction between In 2 O 3 and CeO 2 , leading to the excellent catalytic performance of the In/Ce-BDC-derived catalyst.
研究领域:
化学工程
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催化
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材料科学
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能源
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）