COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Chunhua Liang,Chuantao Wang,Kaixuan Xu,Hongbin He,Qiangen Li,Chunming Yang,Xiaoming Gao
The benzaldehyde (BAD) produced by the benzyl alcohol (BA) oxidation method is comprehensively applied to food and pharmaceutical fields. However, the selectivity and conversion of photocatalytic selective oxidation of BA in aqueous solution are still far from expectation. Herein, N-CQDs/CdS composites were synthesized by the in-situ precipitation method. N-CQDs served as an "Electronic Warehouse" to boost the separation efficiency of the carrier. The electron transferred from CdS to N-CQDs made electron on the N-CQDs surface enrich, which was conducive to the formation of superoxide radicals (·O 2 - ).·O 2 - and h + could efficiently oxidize BA to BAD. In addition, according to density functional theory (DFT), the adsorption energies of BA and BAD on N-CQDs/CdS were distinctly greater than that of CdS. BAD tended to desorb from the 7.5 N-CQDs/CdS surface, and BA preferred to adsorb on the CdS surface. However, BAD was difficult to desorb from the CdS surface, resulting in the poisoning of CdS. 7.5 N-CQDs/CdS exhibited the BA conversion of 60.4% and BAD selectivity of 99%, which was 2.2 times higher than that of original CdS. This work was expected to provide a theoretical basis for improving photocatalyst carrier separation efficiency and alcohol selective oxidation performance.
研究领域:
材料科学
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催化化学
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环境科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Yanhui Niu,Wenshuo Zhang,Huiyun Xia,Ningning Li,Lifang Song,Xu Li,Liying Cui
As well known, the apparent structure and chemical composition of self-cleaning photocatalytic coatings are crucial for their application. In this study, C 3 N 4 with a large specific surface area was introduced into N-CQDs/Bi 2 WO 6 to construct a highly catalytic active catalyst (CBW-0.5), which continuously degraded 57.7 % of NO. A robust self-cleaning photocatalytic coating (CCBW-B) was prepared by firmly bonding CBW-0.5 to the substrate through a layered spraying process. CBW-0.5 endowed CCBW-B with high catalytic activity, maintaining a degradation rate of 64.9 % for NO, and most of the surface organic dye contamination was degraded after 36 h. Due to the appropriate arrangement of low surface energy substances and micro/nano particles on the surface, CCBW-B with a graded cross network on the surface has contact angles (CA) of 156°/145° for water/olive oil, respectively. The influence of each component of CCBW-B on its photocatalytic and liquid repellent ability was studied, and the patterns for the differences in coating performance due to the changes in surface roughness structure caused by different layer distributions was discussed. In addition, the mechanism for the excellent performance of CCBW-B was explored using SEM, specific surface area, and the theory of the generation and distribution of air pockets. Finally, the durability and self-cleaning ability of CCBW-B were tested, and the synergistic mechanism of self-cleaning and photocatalysis was also provided.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
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2024
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IF 4
He Mei,Jingcheng Huang,Guixin Wang,Kun Chen,Huili Wang,Xuedong Wang,Wenwei Wang
Herein, we engineered a novel pH-responsive ratiometric assay by virtue of the composite system of Ce 3+ -enhanced glutathione-encapsulated copper nanoclusters (GSH-CuNCs-Ce 3+ ) and N-doped carbon quantum dots (N-CQDs). The GSH-CuNCs-Ce 3+ and N-CQDs were fabricated using one-pot chemical reduction and hydrothermal approaches, respectively, and their morphologies as well as physical and chemical properties were testified in detail by a series of characterization techniques. At 350 nm excitation wavelength, the GSH-CuNCs-Ce 3+ /N-CQDs system (GCC-NC) featured the 440/650 nm dual-emitting property. The ratios of fluorescence intensities (F 650 /F 440 ) demonstrated a strong pH-dependence from 3.0 to 5.0 with a coefficient of determination of 0.9982. Consequently, the GCC-NC system was feasible for constructing a pH-responsive dual-emitting fluoroprobe. Based on the catalytic effect of acetylcholinesterase on acetylcholine to yield acetic acid and further trigger varying solution pH, the as-constructed GCC-NC fluoroprobe was satisfactorily applied for detecting malathion . Under optimized conditions, the newly developed GCC-NC fluoroprobe supplied a wider linear range (0.25–200 μM), lower detection limit (0.075 μM), satisfactory recoveries (96.3–106.2%) and higher precision for malathion in several kinds of fruit juice samples. The fortified experiments by malathion’s structural analogues and metal ions provided compelling evidence that this fluoroprobe had strong anti-interference capacity and high specificity for malathion. These findings render us to believe that the as-constructed pH-responsive dual-emitting fluoroprobe holds great promise in trace malathion assay in food matrices.
研究领域:
分析化学
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食品安全
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环境科学
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产品关联
DOI
高影响因子
TALANTA
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2022
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IF 6.556
Xuemei Ma,Jiayi Yu,Lin Wei,Qian Zhao,Liyong Ren,Zhiyong Hu
Simultaneous selective determination of Fe (Ⅱ) and Fe (Ⅲ) is of great significance to the study of iron ion tracking and release of iron supplement in gastric fluid. In this paper, a composite material (N-CQDs/AgNPs/β-CD) was prepared by a one-pot method. The various characterizations confirmed the silver nanoparticles (AgNPs) grew in situ on the surface of nitrogen-doped carbon quantum dots (N-CQDs), and the β-cyclodextrin (β-CD) and AgNPs linked together by Ag–O bonds finally presented gourd-like nanoparticles on the surface of N-CQDs. Then, N-CQDs/AgNPs/β-CD modified glassy carbon electrode (GCE) was applied to detect Fe(II) and Fe(III) simultaneously. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results confirmed that N-CQDs/AgNPs/β-CD enhanced electrode performances because of the synergistic effect between N-CQDs, AgNPs and β-CD. The sensor was successfully applied for the determination by differential pulse voltammetry (DPV) of Fe(II) and Fe(III) released from four iron supplementations in simulated gastric fluid (SGF).
研究领域:
分析化学
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生物医学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Zhiquan Chen,Didi Yang,Zhenda Liang,Yongtao Xu,Yijun Pang,Gang Xu,Chaoxiang Chen,Kunyu Ma,Li Zhou,Bing Yan
Microbial pollution and antibiotic contamination can pose a serious threat to human health. The rational development of efficient and low-cost methods is critical to solving these problems. In this study, novel Z-scheme heterojunctions consisting of Yb-MnO 2 and nitrogen-doped carbon quantum dots (N-CQDs) were fabricated to achieve efficient photocatalytic degradation of tetracycline (TC) and the destruction of bacteria ( Escherichia coli used as a model). Results showed that the Yb-doping strategy improves the characteristics of host MnO 2 by weakening the lattice interface and increasing its surface area. Compared with Yb-MnO 2 , Yb-MnO 2 /N-CQDs heterostructures exhibited superior photocatalytic activity in TC degradation under simulated solar light. The remarkable photocatalytic and mild oxidation abilities of Yb-MnO 2 /N-CQDs led to an impressive 97.88% removal rate of TC. Additionally, the structure displayed robust resistance to various ions and broad pH levels. Notably, the Yb-MnO 2 /N-CQDs heterostructures exhibited excellent bactericidal activity, with no observed bacterial resistance even after 20 consecutive trials. Furthermore, quenching experiments demonstrated that 1 O 2 and O 2 − were the primary radicals involved in the Yb-MnO 2 /N-CQDs-based photocatalysis process. The remarkable photocatalytic activity of Yb-MnO 2 /N-CQDs can be attributed to two key factors. Firstly, the large surface area and abundant oxygen defects provide rich active sites for reactant degradation. Secondly, the Z-scheme heterojunctions formed between Yb-MnO 2 and N-CQDs effectively facilitate the separation of photogenerated electron-hole pairs and increase the reduction/oxidation potentials for reactive oxygen species generation. This study presents a promising novel photocatalyst for the facile and energy-saving treatment of antibiotic and microbial pollution, and it may provide new insight into the design of highly efficient heterogeneous photocatalysts.
研究领域:
环境科学
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材料科学
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微生物学
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产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
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2025
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IF 5.1
Zhirou Xu,Zhengtong Wu,Xuyang Sun
An ultrasensitive fluorescence immunosensor based on silver nanoparticles@ nitrogen-doped carbon quantum dots (Ag NPs@N/CQDs) and exploiting the quenching effect of gold nanoparticles (Au NPs) was fabricated for squamous cell carcinoma antigen (SCCA) detection. Ag NPs@N/CQDs were immobilized on the surface of an indium tin oxide (ITO) electrode and then coupled with the primary antibody of SCCA. The primary antibody captured SCCA on the ITO electrode, forming an immune complex with the secondary antibody labeled with gold nanoparticles, thereby constructing a sandwich-structured fluorescent sensor. Using the prepared sensor, a new method for detecting trace amounts of SCCA in human serum was established. Owing to the effective quenching of fluorescence intensity of Ag NPs@N/CQDs by Au NPs, combined with the presence of a sandwich immune structure, the sensor exhibits high sensitivity and selectivity. The method demonstrates a linear range of 2 − 4000 fg mL −1 and a detection limit of 0.87 fg mL −1 . The the recovery rate for real serum samples was between 94.45 % to 103.43 %.
研究领域:
生物医学工程
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肿瘤学
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纳米技术
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产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
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2024
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IF 7.7
Yang Wang,Xiaoqing He,Peng Gao,Li Feng,Liqiu Zhang
Limited utilization of photogenerated charge carriers in titanium dioxide under visible light have hinder its application development. To address this challenge, a novel N-doped carbon quantum dots (N-CQDs) and oxygen vacancies (OVs) synergistically decorated on TiO 2 (P25) was synthesized through a facile one-step hydrothermal method. Under visible light irradiation, the first order reaction rate constants of formaldehyde (HCHO) photocatalytic oxidation by OVs-TiO 2 and N-CQDs/OVs-TiO 2 was significantly higher than that of pristine P25, with 10.1 and 16.7 folds increase, respectively. Characterization results confirmed the generation of OVs on the surface of N-CQDs/TiO 2 composite. The optical and electrochemical experiments suggested the electron capture center effect of OVs and the properties of N-CQDs in unique up-converted photoluminescence , efficient charge separation, as well as significant adsorption in visible light region. In addition, the work function also clarified that photoelectrons could transfer from N-CQDs to OVs-TiO 2 . Furthermore, different relative humidity and electron paramagnetic resonance (EPR) experiments demonstrated that the hydroxyl radical (•OH) was the dominant reactive radical in HCHO photodegradation . The •O 2 − could also enhance the photodegradation efficiency of HCHO. This work provides an in-depth understanding on the complementary roles of N-CQDs and OVs and is helpful for designing metallic oxide photocatalysts for volatile organic compounds removal.
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
PubMed
高影响因子
ChemistrySelect
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2023
·Vol. 8
·期 37
·e202302830
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IF 2.1
Hongyan Guo,Shu Wang,Lian Duan,Yue Sun,Shuwei Chen
Graphical A method for the synthesis of Nitrogen-Doped Carbon quantum Dots (N-CQDs) with 4-aminosalicylic acid and tartaric acid is proposed. The synthesized N-CQDs exhibit strong fluorescence and good photostability and can selectively detect CN − in solution. Selective and sensitive detection of Cyanide (CN − ) is critical essential due to it is one of the most lethal chemicals and threat to human health. In this study, nitrogen-doped carbon quantum dots (N-CQDs) were synthesized by one-step hydrothermal method using 4-aminosalicylic acid and tartaric acid as raw materials. The prepared N-CQDs were spherical particles with good water solubility and uniform particle size distribution, the optimal excitation and emission wavelengths of N-CQDs were 495 nm and 514 nm, respectively. Based on the selective fluorescence quenching effect between CN − and N-CQDs, achieving accurate and rapid detection of CN − . Fluorescence quantum yield (PLQY) of N-CQDs is 39 %, and the other competing anions showed little or no interference to CN − . For highly sensitivity detections of N-CQDs under optimal conditions, the fluorescence quenching degree was linearly correlated with the CN − concentration in the range of 0–100 μM (R 2 =0.9929).
研究领域:
材料科学
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环境科学
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分析化学
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产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2020
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IF 3.807
Cong Luo,Jianghua Yang,Jinling Li,Shijie He,Bowen Meng,Tao Shao,Qiankun Zhang,Dongxia Zhang,Xibin Zhou
A strategy for the synthesis of Au@N-CQDs@Pd three-layer core-shell nanoparticles without the use of any surfactant is proposed in this work. Herein, N-doped carbon quantum dots (N-CQDs) are used as the reducing agent, stabilizing agent, and shape-directing agent. The morphology and structure of the final product were characterized by Transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and X-ray powder diffraction (XRD). The electrocatalytic test indicates the as-synthesized Au@N-CQDs@Pd 20 exhibites excellent activity for methanol oxidation in alkaline media, which is approximately 6 times higher than commercial Pd/C. And its resistance to CO and stability are also greatly improved. This work provides a simple and straightforward approach to prepare bimetallic core-shell electrocatalyst by using CQDs with high catalytic activity for alkaline fuel cells .
研究领域:
材料科学
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电化学
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纳米技术
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2024
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IF 2.7
Bin Li,Aolin Wu,Mengjing Zhou,Ying Wang,Zhigang Hu,Lihua Su
In this paper, nitrogen-doped carbon quantum dots (N-CQDs) were prepared by using citric acid as a carbon source and ethylenediamine as a nitrogen source. Then, N-CQDs were added into a deep eutectic solvent (DES) synthesized from acrylamide (AM), urea (U), and choline chloride (ChCl). The N-CQDs/P(AM-U-ChCl) composite hydrogels were prepared by light polymerization. The chemical composition and microstructure of N-CQDs/P(AM-U-ChCl) composite hydrogels were characterized in detail using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). This article further explored the influence of the content of N-CQDs on the mechanical properties, adsorption properties, and detection performance of the composite hydrogel. The results showed that the composite hydrogels exhibited the best mechanical properties when N-CQDs' content was 0.3 wt%. The adsorption performance of N-CQDs/P(AM-U-ChCl) composite hydrogels for Fe3+ was significantly enhanced due to the carboxyl groups contained in N-CQDs. In detecting tert-butylhydroquinone (TBHQ), the composite hydrogel showed a good linear correlation in the concentration range of 0–200 mg L−1, and the detection limit of TBHQ reached 0.849 mg L−1. This study provides a new idea for preparing composite hydrogel materials with excellent mechanical properties and functionality. Also, it demonstrates their potential application value in heavy metal ion adsorption and organic molecule detection.
研究领域:
材料科学
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环境科学
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分析化学
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Donghuan Meng,Ye Lei,Menghan Pang,Jianrong Qiu,Chenghua Fan,Yuyan Feng,Dongbo Wang
In the graphitic carbon nitride-based photocatalytic reaction, the redox ability and electron transport ability of photocatalyst have an important influence on its activity. The Photo-Fenton reaction system was constructed by modifying N-doped carbon quantum dots (N-CQDs) on the surface of supramolecular self-assembled carbon nitride and introducing Fe ions into the carbon nitride planar structure . The xFe/N-CQDs/MCN1 catalysts with different iron contents were prepared, which had significant degradation effect on organic pollutants . Among them, 0.2Fe/N-CQDs/MCN1 degraded 76% of ciprofloxacin (CIP) within 120 min. Various characterizations demonstrate that photocatalytic activity are enhanced due to the surface modification of N-CQDs enhancing electron transfer rate on the surface of photocatalysts and the doping of Fe ions providing active sites for Fenton reaction . At the same time, the formation of chemical bonds limits the leaching of iron and avoids secondary environmental pollution . These results indicate that the novel catalyst has excellent application potential in the field of environmental photocatalysis .
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
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Jiaqi Guo,Fangliang Gao,Dongyang Li,Xingjun Luo,Yiming Sun,Xingfu Wang,Zhilin Ran,Qibao Wu,Shuti Li
Self-healing materials arouse much attention because of their recoverable morphologies during (dis)charge. Herein, we report an effective and practical synthesis strategy that can adequately utilize the self-healing feature to achieve advanced integrative performance. The hollow Ga2O3@nitrogen-doped carbon quantum dot (H-Ga2O3@N-CQD) nanospheres are synthesized via a facile approach as an anode material for lithium-ion batteries (LIBs). In this anode, the self-healing capability is derived from the Ga generated in the conversion reaction. On account of the feasible structure design and the binding N-CQD coating, the material structure can be well preserved during (dis)charging. As a result, the anode material delivers an initial discharge capacity of 1348.5 mAh g–1 at 0.1 A g–1 and an invertible capacity of 700.5 mAh g–1 under 0.5 A g–1 after 500 cycles. Endowed by the unique structural design, the H-Ga2O3@N-CQDs can deliver high-current-density circulation performance and long-term cycle stability, which has prospects for large-scale applications in high-energy-density LIBs. Meanwhile, the rational framework design offers new insights into the structure-building construction of self-healing materials.
研究领域:
材料科学
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电化学
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纳米科技
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能源存储
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功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）