RSC Advances
·
2017
·Vol. 7
·期 65
·40952-40956
·
IF 3.108
Chunlin Tan,Xiuya Su,Chao Zhou,Baoju Wang,Qiuqiang Zhan,Sailing He
Red-emitting carbon dots (C-dots) were synthesized from p-phenylenediamine (p-PD) aqueous solution with nitric acid (HNO3) assistance by hydrothermal reaction at 200 °C for 2 h. p-PD aqueous solution can be transferred to C-dots (or poly(p-PD)) with (or without) the addition of acid. Different acid systems, such as HNO3, H3PO4 and HF, can directly synthesize red-emitting C-dots, and the fluorescence can be enhanced by increasing the strength of acids. N-CDs, 3.46 nm-average-sized C-dots, prepared in dilute HNO3, have a quantum yield of 15.8% with unique, excitation-wavelength independent emission in the red region (600 and 680 nm) and a broad visible excitation band. Carboxyl, ester and hydroxyl groups on the C-dots surface directly lead to red emission. N-CDs have a certain selective specificity for Fe3+ detection and the linear range is 10–300 nmol L−1 with a limit of determination of 1.9 nmol L−1.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Ying Wang,Jian He,Pan Wu,Dingyuan Luo,Runhua Yan,Hao Zhang,Wei Jiang
In this study, a common refractory aquaculture hybrid wastewater containing copper and tetracycline (TC) was treated to simultaneously remove such pollutants through a formic-acid-assisted photocatalysis process with TiO2 as the photocatalyst. The results show that pure aqueous TC can be completely photodecomposed by TiO2, although the removal rate of pure Cu ions through photocatalysis without the addition of a scavenger can be neglected. For simultaneously photodegrading TC–Cu(II) hybrid wastewater, the TC degradation rate is accelerated, whereas the Cu(II) removal rate remains at 20% through adsorption. TC cannot promote the photoreduction of Cu(II) as a sacrificial agent, and its intermediate products form a stable complex with Cu(II), hindering further reduction. The addition of formic acid effectively releases Cu ions from the complex as a pH regulator and enhances the photocatalysis process as a hole scavenger. Through the addition of formic acid after complete TC photooxidation, the final chemical oxygen demand (COD) and Cu concentration were only 8 and 0.4 mg/L, respectively. This study provides a simple and promising method for simultaneously treating TC–Cu(II) hybrid wastewater using formic-acid-assisted TiO2 photocatalysis.
研究领域:
环境科学
·
污染控制
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Ji Liu,Hao Fu,Bin Hu,Guan-zheng Zhou,Shou-gang Wei,Zhen-xi Zhang,Qiang Lu
Pyrolysis, a promising thermochemical conversion technique, can convert lignocellulosic biomass into various value-added products. Herein, the selective production of 1,4:3,6-dianhydro-α- d -glucopyranose (DGP) was achieved through fast pyrolysis of cellulose based on oxalic acid-assisted torrefaction (OAT) pretreatment. The mixture of cellulose and oxalic acid first underwent torrefaction, followed by fast pyrolysis to yield DGP. Simultaneously, the air atmosphere was considered to facilitate the formation of esterification intermediates, thereby promoting the formation of DGP. The effects of torrefaction temperature, oxalic acid amount, as well as pyrolysis temperature were carefully explored for DGP production. A yield of 9.6 wt% and a selectivity of 57.5 % for DGP were achieved from the micro-scale pyrolysis of cellulose under the optimized conditions. In lab-scale tests, the DGP yield reached 12.5 wt% from cellulose. The OAT-based pyrolysis was confirmed to be applicable to the waste cellulose-rich materials, with a DGP yield of 8.2 wt% from waste cotton and 6.0 wt% from spent paper in lab-scale experiments. Additionally, the OAT-based pyrolysis also showed the potential for poly-generation of DGP and formic acid at different stages.
研究领域:
能源与燃料化学
·
生物质转化技术
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2021
·
IF 5.645
Wei Liu,Chenxi Ning,Ranran Sang,Qingxi Hou,Yonghao Ni
Value- added utilization of carbon-rich lignin has become an urgent and attractive research topic due to its abundance, low cost, and sustainability. How to convert lignin in an efficient and green strategy is the bottleneck limiting its valorization. Herein, a phosphorous acid (P) assisted hydrothermal process to produce lignin-derived graphene quantum dots (P-LGQDs) was developed. The as-prepared P-LGQDs was comprehensively characterized, and explored in photocatalysis. The P-LGQDs have a narrow particle size distribution, excellent electronic and optical properties, and a good pH-responsiveness. The P-LGQDs was further used to construct P-LGQDs/g-C 3 N 4 heterojunction, showing excellent photocatalytic degradation ability towards methylene blue and model lignin (94.6 % and 93.1 %, respectively). This present study offers a universal strategy for the value-added utilization and valorization of lignin.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2017
·
IF 2.429
Song LI,Song YE,Xiao CHEN,Tianhua LIU,Zhuang GUO,Deping WANG
Yb 3+ and Er 3+ ions co-doped NaYF 4 nanocrystals were synthesized with different amounts of NaOH via oleic acid (OA)-assisted hydrothermal process. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and photoluminescence spectra were used to characterize the products. The result indicated that the introduction of NaOH into the initial reaction solution effectively promoted the cubic (α-) to hexagonal (β-) phase transition of NaYF 4 :Yb 3+ ,Er 3+ nanocrystals, while excessive amount of NaOH favored the formation of α-NaYF 4 :Yb 3+ ,Er 3+ nanocrystals. Besides, with the increase of NaOH amount, the morphologies of β-NaYF 4 :Yb 3+ ,Er 3+ nanocrystals varied from irregular nanobranch to uniform nanorod. Further investigation revealed that the addition of NaOH could facilitate the deprotonation of OA, leading to the formation of oleate (OA − ), and meanwhile increased the concentration of OH − ions, inducing consequently the phase transition and morphology evolution of NaYF 4 :Yb 3+ ,Er 3+ nanocrystals. Moreover, the upconversion luminescence properties of NaYF 4 :Yb 3+ ,Er 3+ nanocrystals were systematically investigated. It was found that the upconversion emissions not only depended on the phase and morphology but also were influenced by the surface groups.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Peng Yang,Xin Xi,Tao Huang,Qianqian Zhong,Biao Jiang,Ruili Liu,Dongqing Wu
An acid-assisted vacuum filtration approach is developed in this work to fabricate perylene diimide (PDI) and single wall carbon nanotube (SWCNT) based organic lithium ion battery (LIB) cathodes by using concentrated sulfuric acid (H 2 SO 4 ) as the solvent. PDI and SWCNT can be readily dispersed in H 2 SO 4 by the protonation of their aromatic frameworks, thus rendering the effective combination of them in the acidic solution. The resulting PDI/SWCNT films are highly appealing flexible cathodes for LIBs by associating the intriguing electrochemical activity of PDI with the excellent electric conductivity and mechanical stability of SWCNT. Either with lithium foils or pre-lithiated carbon clothes as the anodes, the LIBs with PDI/SWCNT cathodes can deliver highly stable electrochemical performances in terms of rate capability and cycling stability. The PDI/SWCNT cathodes also have very good mechanical stability, enabling the LIBs based on them to reserve the battery performances at different bending states. The excellent electrochemical stability of the PDI/SWCNT cathodes is attributable to the acidic solution based processing method, which is expected to be expanded in the electrode fabrication of various organic secondary batteries with π-conjugated components.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
MRS Advances
·
2020
·Vol. 5
·期 31
·1661-1670
·
IF 0
Xing Xianj,Li Shan,Song Yuq,Ge Yingz,Zhang Xuef,Jiang Wen,Zhang Xianwen
YBO 3 :Eu 3+ crystals with flower-like hierarchitecture are readily synthesized through a folic acid assisted hydrothermal process using polyborate precursors in the aqueous solution. It was found that the pH value, borate/yittrium ratio and the mass of folic acid take effects on the morphology and photoluminescence emission intensity of YBO 3 :Eu 3+ crystals. The product with the small flower-like hierarchitecture was obtained under the conditions of pH value at 9, borate/yittrium ratio at 2 and the mass of folic acid at 0.44 g, showing the strongest photoluminescence intensity. The growth process of the YBO 3 :Eu 3+ flowers and microflowers was invesitgated based on the time-dependent experiments, which showed that the growth mechanism of the flower-like hierarchitecture follows an in situ growth rather than self-assembly process as reported previously. Such a hydrothermal route using folic acid as a capping agent may provide a green and effective method for fabricating useful and complex 3D architectures of LEDs phosphors.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 3.7
Shaopeng Li,Weichao Li,Yun Wu,Xianming Zheng,Xuehui Zhao,Ning Nan,Hongwei Zhang
The performance of supported catalysts is significantly affected by the dispersion degree of the active components on the support. In this study, citric acid (CA) was used as a modifier to prepare Al 2 O 3 supported Mn-Ce oxides (Mn-Ce/CA-Al 2 O 3 ) by the impregnation-calcination method. The characterization results showed that adding citric acid enhanced the dispersion of Mn-Ce oxides on the support, rendering Mn-Ce/CA-Al 2 O 3 with a larger specific surface area and abundant surface hydroxyl groups, thereby providing more reaction sites for catalytic ozonation. The Mn-Ce/CA-Al 2 O 3 exhibited excellent catalytic ozonation performance in degrading Reactive Black 5 (RB5) dye. It achieved nearly complete decolorization of RB5 within 60 min, with a COD removal efficiency of 60%, which was superior to the sole ozonation (30%). Furthermore, the Mn-Ce/CA-Al 2 O 3 system demonstrated significant degradation of RB5 over a wide pH range of 3–11. Based on the XPS and EPR analysis results, a preliminary mechanism of catalytic ozonation over the Mn-Ce/CA-Al 2 O 3 was proposed. The redox cycle of Mn 3+ /Mn 4+ and Ce 3+ /Ce 4+ effectively accelerated the electron transfer process, thus promoting the generation of reactive oxygen species (ROS) and improving the degradation of RB5. Meanwhile, the Mn-Ce/CA-Al 2 O 3 exhibited superior catalytic stability and effective treatment capabilities for real dye wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Yao Chen,Fei Ding,Aung Khaing,Dong Yang,Zhongyi Jiang
Graphic carbon nitride (g-C 3 N 4 ) is a kind of promising organic semiconductor in visible light driven photocatalysis due to its metal free, high physicochemical stability and appealing electronic band structure . In this work, a porous hexagonal-prism g-C 3 N 4 (ACNH) photocatalyst was successfully synthesized via an acetic acid-assisted supramolecular assembly approach followed by calcination . The resulting ACNH materials have a corrugated and closely packed porous structure, which is composed of thin layers about 30 nm in thickness. The specific surface area of ACNH is as high as 67.7 m 2 g −1 , which is approximately 8-fold of bulk g-C 3 N 4 . Moreover, the porous structure induces the red shift of the absorption edge and facilitates the photo-induced charge separation of g-C 3 N 4 . Compared to bulk g-C 3 N 4 , the ACNH sample exhibits almost 13-fold improvement for the RhB degradation with the rate constant of 0.053 min −1 . This finding suggests that the acid-assisted supramolecular assembly may become a feasible method to synthesize g-C 3 N 4 -based photocatalysts with higher surface area and photocatalytic activity .
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2020
·
IF 7.098
Qin Li,Zhipeng Liao,Xiaofeng Fang,Jia Xie,Linhan Ni,Dapeng Wang,Junwen Qi,Xiuyun Sun,Lianjun Wang,Jiansheng Li
In this work, a novel tannic acid assisted interfacial polymerization (TAIP) method was developed for preparing loose nanofiltration membranes (LNMs). Piperazine (PIP) and tannic acid (TA), two kinds of common monomer for interfacial polymerization (IP), were employed to deposit on substrate for the TAIP process. The TAIP process resulted in enlarged pores in the skin layer due to the longer monomers, thus achieved considerable permselectivity in separating salts from dye/salt mixture solution. The optimal TAIP membrane (M4) exhibited high permeability (32.57 LMH·bar − 1 to Congo Red solution), reasonable rejection to dyes (99.40% and 99.19% for Congo Red and Rose Bengal, respectively) and satisfactory transport to salts (90.59% to Na 2 SO 4 and 97.75% to NaCl). Meanwhile, this membrane retained high performance in dye/salt separation (7.16 LMH·bar − 1 of permeability, 97.47% of CR rejection and 2.55% of NaCl retention) under even as high as 6 wt% of salt concentration . Moreover, TAIP LNM showed high stability throughout a 30-hour-long running test to separate salts from dye/salt mixture solution. We anticipated the TAIP methodology, together with the consequential LNM, to provide a potential candidate for dye/salt separation application.
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
GREEN CHEMISTRY
·
2020
·Vol. 22
·期 3
·850-859
·
IF 9.48
Yang Qian,Ze-Jun Li,Xian-Long Du,Qi Zhang,Yi Zhao,Yong-Mei Liu,Yong Cao
Development of a highly efficient and robust catalyst with reduced usage of noble metals is extremely desirable for selective hydrogenations of furan-containing bio-based feedstocks, which represents an attractive and sustainable alternative to petrochemical resources. Herein, we describe a new type of well-dispersed Ru subnanoclusters (ca. 0.50 wt%) supported on commercial P25 TiO2 material obtained from a facile and effective amino acid-assisted deposition–precipitation strategy. The as-synthesized catalyst exhibits superior catalytic activity and selectivity for direct hydrogenation of industrially important furfural as well as a range of structurally diverse bio-based furanic compounds to their corresponding fully hydrogenated derivatives. An average turnover frequency (ATOF) value as high as 367 h−1 at 80 °C and 4 MPa H2 is obtained, which is the highest reported value. This catalyst also shows stable furfural total hydrogenation in 5 reaction cycles conducted at 80 °C (52 mmol-scale, turnover number up to 12 500). In terms of the kinetic and structural characterizations, the key performances of the ultrasmall Ru clusters are proposed to mainly originate from an enhanced number of unsaturated surface Ru atoms and change in local coordination environment. Our work highlights the importance of the subnanometric size of Ru clusters in the advancement of efficient and affordable approaches towards bio-based chemical production.
研究领域:
催化化学
·
生物质化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Mengli Yan,Zhuo Liu,Shuang Li,Jianwang He,Yan Xu
Metal–organic frameworks (MOFs), known for their exceptional gas permeability and abundant active sites, are a class of porous coordination polymers that can serve as ideal candidates for constructing advanced gas sensors. However, the limitations of low electrical conductivity and inadequate stability under extreme conditions hinder their advancements in gas-sensing applications. Moreover, a single MOF structure occasionally demonstrates insufficient selectivity toward specific gases, failing to meet stringent sensing requirements. To overcome these challenges, this study innovatively constructs an MOF-on-MOF architecture by etching Ti-MOF into a hollow cage-like structure with l-glutamic acid and connecting it with Ni2+ ions to form Ni-MOF via peptide bonds. The approach not only enhances the specific surface area and pore structure of the material but also facilitates carrier transport rates at the interface by effectively linking the two MOFs. The resultant MOF-on-MOF structure exhibits remarkable selectivity and sensitivity in detecting triethylamine gas at a low operating temperature of 140 °C, along with exceptional reproducibility and long-term stability. This work demonstrates a novel amino acid-assisted feasible and simple method to construct MOF-on-MOF material, showcasing immense potential in high-performance gas detection applications.
研究领域:
材料科学
·
化学传感器
·
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）