共查询到9条相似文献,搜索用时 15 毫秒
1.
Varsha Raveendran Adukamparai Rajukrishnan Suresh Babu Neeroli Kizhakayil Renuka 《RSC advances》2019,9(21):12070
Highly luminescent carbon dots (CDs) are obtained from mint leaves adopting a simple and cost effective route devoid of additional chemical reagents and functionalization. The as-synthesized CDs are characterized by TEM, FE-SEM, XRD analysis, FTIR, Raman, UV-visible and photoluminescence spectral studies. The results reveal that the CDs have an average diameter of 4 nm with a hydroxyl-rich surface. The luminescence of the dots was excitation dependent and was stable towards variation in the medium. The system could perform as a promising on–off–on fluorescent sensor for the selective and sensitive dual analyte recognition of Fe3+ and AA with a detection limit of 374 nM and 79 nM, respectively. The mechanism of ascorbic acid sensing by the CD–Fe3+ unit is established by identifying the binding sites of the biomolecule with the metal ion by examining the behaviour of the sensor in the presence of ascorbic acid derivatives.Highly luminescent carbon dots (CDs) are obtained from mint leaves adopting a simple and cost effective route devoid of additional chemical reagents and functionalization. 相似文献
2.
Lihong Shi Dan Chang Guomei Zhang Caihong Zhang Yan Zhang Chuan Dong Lanling Chu Shaomin Shuang 《RSC advances》2019,9(70):41361
Green-fluorescent N-doped carbon dots (N-CDs) have been successfully fabricated using hydrothermal treatment of tyrosine and urea. The N-CDs obtained showed excitation-independent emission, superior stability and strong photoluminescence with a quantum yield of ca. 9.8%. Based on these striking behaviors, the as-prepared N-CDs have been utilized in Co2+ detection and temperature sensing. Due to an inner filter effect, the N-CDs obtained were dramatically quenched by Co2+ with linear ranges of 0.1 μM–10 μM, 25 μM–275 μM and 300 μM–400 μM, and they had a detection limit of 0.15 μM. The use of the as-prepared N-CDs has been extended to visualize Co2+ fluctuations in living cells. Additionally, the N-CDs obtained have also been applied for use as a temperature sensor with a linear range of 25–80 °C.Green-fluorescent N-doped carbon dots (N-CDs) have been successfully fabricated using hydrothermal treatment of tyrosine and urea. 相似文献
3.
Guohua Dong Kun Lang He Ouyang Wenzhi Zhang Liming Bai Shijie Chen Zhuanfang Zhang Yueyue Gao Zhonghua Mu Xiaodan Zhao 《RSC advances》2020,10(55):33483
Nitrogen/phosphorus-doped carbon dots (N, P-CDs) with a quantum yield as high as 76.5% were synthesized by carbonizing maize starch via a facile ethanol solvothermal approach. Transmission electron microscopy (TEM) measurement shows that the as-prepared N, P-CDs displayed a quasi-spherical shape with a mean size of ca. 2.5 nm. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy disclosed the presence of –OH, –NH2, –COOH, and –CO functional groups over the surface of N, P-CDs. On the basis of excellent fluorescent properties with strong blue fluorescence emission at 445 nm upon excitation at 340 nm, these N, P-CDs were adopted as a fluorescent probe towards the effective detection of Fe3+ ions in water. The limit of detection (LOD) was as low as 0.1 μmol L−1 and showed a better linear relationship in the range of 0.1 ∼ 50 μmol L−1. In conclusion, these synthesized N, P-CDs can be efficiently used as a promising candidate for the detection of Fe3+ ions in some practical samples.Nitrogen/phosphorus-doped carbon dots (N, P-CDs) with a quantum yield as high as 76.5% were synthesized by carbonizing maize starch via a facile ethanol solvothermal approach and utilized for the detection of Fe3+. 相似文献
4.
Dansyl-modified carbon dots with dual-emission for pH sensing,Fe3+ ion detection and fluorescent ink
Hua Tian Yongcheng Dai Wenzhe Fu Haifang Liu Mengting Li Meiyuan Lv Xueqiong Yin 《RSC advances》2020,10(61):36971
In this work, a multifunctional ratiometric fluorescence (FL) nanohybrid (CSCDs@DC) was synthesized from chitosan based carbon dots (CSCDs) and dansyl chloride (DC) at room temperature. The CSCDs@DC revealed strong FL intensity, great stability and excellent anti-photobleaching properties. Herein, CSCDs@DC was responsive to pH value in the range of 1.5–4.0 and exhibited color-switchable FL properties between acidic and alkaline environments. In addition, CSCDs@DC showed good selectivity and sensitivity towards Fe3+ ions. A good linear relationship for the Fe3+ ion detection was obtained in the range from 0 μM to 100 μM, with a detection limit of 1.23 μM. What''s more, CSCDs@DC can be used as a fluorescent ink. It expressed superior optical properties after 3 months of storage or continuous exposure to UV light for 24 h. This study suggested that CSCDs@DC had potential in the detection of pH and metal ions, as well as showing promising application in the anti-counterfeiting field.This work provided a new strategy for developing a multifunctional fluorescence platform which had potential in the detection of pH and metal ions, as well as showing promising application in the anti-counterfeiting field. 相似文献
5.
Hydrogen sulfide (H2S) is one of the most plentiful toxic gases in a real-life and causes a collapse of the nervous system and a disturbance of the cellular respiration. Therefore, highly sensitive and selective H2S gas sensor systems are becoming increasingly important in environmental monitoring and safety. In this report, we suggest the facile synthesis method of the Fe2O3 particles uniformly decorated on carbon nanotubes (Fe2O3@CNT) to detect H2S gas using oxidative co-polymerization (pyrrole and 3-carboxylated pyrrole) and heat treatment. The as prepared Fe2O3@CNT-based sensor electrode is highly sensitive (as low as 1 ppm), selective and stable to H2S gas at 25 °C, which shows promise for operating in medical diagnosis and environment monitoring. Excellent performance of the Fe2O3@CNT is due to the unique morphology of the nanocomposites made from uniformly dispersed Fe2O3 nanoparticles on the carbon surface without aggregation.Fe2O3 uniformly dispersed on carbon nanotubes are synthesized using facile oxidative co-polymerization of monomers followed by heat treatment to apply electrode materials for a highly sensitive H2S chemical sensor system. 相似文献
6.
A luminescent Cd(ii) coordination polymer, namely {[Cd(btic)(phen)]·0.5H2O}n (CP-1) (H2btic = 5-(2-benzothiazolyl)isophthalic acid, phen = 1,10-phenanthroline), was constructed through the mixed-ligand method under solvothermal conditions. CP-1 manifests a chain structure decorated with uncoordinated Lewis basic N and S donors. CP-1 exhibits high sensing towards Zn2+, Fe3+ and Cr2O72− ions with fluorescence enhancement or quenching. CP-1 exhibited a fluorescence enhancement for Zn2+ ions through weak binding to S and N atoms, and a fluorescence quenching for Fe3+ and Cr2O72− ions by an energy transfer process. The binding constants were calculated as 1.812 × 104 mol−1 for Zn2+, 4.959 × 104 mol−1 for Fe3+ and 1.793 × 104 mol−1 for Cr2O72−. This study shows CP-1 as a rare multi-responsive sensor material for the efficient detection of Zn2+, Fe3+ and Cr2O72− ions.A luminescent Cd(ii) coordination polymer can act as a multi-responsive sensor for efficiently detecting Zn2+, Fe3+ and Cr2O72− ions. 相似文献
7.
Kui Du Shizhen Niu Li Qiao Yandong Dou Qing Zhu Xinzhi Chen Pengfei Zhang 《RSC advances》2018,8(49):28094
Correction for ‘A highly selective ratiometric fluorescent probe for the cascade detection of Zn2+ and H2PO4− and its application in living cell imaging’ by Kui Du et al., RSC Adv., 2017, 7, 40615–40620.Affiliation c was incomplete in the original publication; the corrected version is shown below.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
8.
Five tetranuclear lanthanide clusters of compositions [Ln4L4(NO3)2(Piv)2]·2CH3OH (Ln = Gd (1), Tb (2), Dy (3), Ho (4), Er (5); H2L = 2-(((2-hydroxy-3-methoxybenzyl)imino)methyl)-6-methoxyphenol; Piv = pivalic acid) were synthesized under solvothermal conditions. The structures of 1–5 were characterized by single-crystal X-ray crystallography. Complexes 1–5 possess a zig-zag topology with [Ln4O6] cores being formed by the fusion of oxygen atom-bridged two [Ln2O2] moieties. Direct-current magnetic susceptibility studied in the 2–300 K range revealed weak antiferromagnetic interactions in 1, 2, 4, 5 and ferromagnetic interactions in 3. Complex 3 exhibits single molecule magnet (SMM) behavior. The luminescence studies indicated that complex 2 can serve as highly sensitive and selective luminescent materials for Fe3+, CrO42−, Cr2O72− and 4-nitroaniline (4-NA), demonstrating that complex 2 should be a potential candidate for multi-responsive luminescent sensor.Five tetranuclear lanthanide clusters were synthesized. Dy4 complex exhibits single molecule magnet (SMM) behavior and Tb4 compound shows sensing properties towards Fe3+, CrO42−, Cr2O72− and 4-nitroaniline (4-NA). 相似文献
9.
Zoleikha Hajizadeh Fereshte Hassanzadeh-Afruzi Diana Fallah Jelodar Mohammad Reza Ahghari Ali Maleki 《RSC advances》2020,10(44):26467
In the present study, Cu(ii) immobilized on an Fe3O4@HNTs–tetrazole (CFHT) nanocomposite was designed and prepared. For this, halloysite nanotubes (HNTs) as natural mesoporous substances were modified during several chemical reactions. The synthesis of the CFHT nanocomposite was investigated step by step with the required physicochemical techniques such as FT-IR, EDX, SEM, TEM, XRD, VSM, TGA and CHNS analyses. After ensuring that the nanocomposite was successfully prepared, its catalytic application in the synthesis of the 5-substituted 1H-tetrazole derivatives via multicomponent reactions (MCRs) between aromatic aldehydes, malononitrile, and sodium azide was assessed. According to the experimental results, the prepared nanocomposite exhibited excellent capability for conducting this MCR reaction. All desired products were obtained in a short reaction time (30–40 min) with high productivity (90–97%) and without a complicated workup procedure. Furthermore, the magnetic property of the synthesized heterogeneous nanocomposite empowers it to be recovered and reused in five times successive reactions without any significant reduction in reaction efficiency. Moreover, the remarkable antibacterial activity of the nanocomposite against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was evaluated by agar diffusion and plate-count methods. The zones of inhibition were around 16 and 20 mm for E. coli and S. aureus bacteria, respectively. Also, colony analysis confirms the killing of bacteria by using the CFHT nanocomposite.In the present study, Cu(ii) immobilized on an Fe3O4@HNTs–tetrazole (CFHT) nanocomposite was designed and prepared. 相似文献