-
近年来,荧光纳米材料因在光催化、生物传感、消毒、离子检测、光电器件和污染物去除等许多领域具有广阔的应用前景而备受关注[1-4]. 荧光纳米材料包括半导体量子点、氮化碳、纳米金刚石、碳纳米管、石墨烯量子点、碳点以及各种复合材料. 含重金属的量子点具有毒性,故环保型荧光纳米材料的制备和应用成为重要的发展趋势.
氮化碳是一种非常有前途的应用材料[5],目前已广泛用于水分解、太阳能传输、污染物去除和检测等领域[6-8],一般通过高温热解工艺由富含氮的前体(如三聚氰胺,氰胺和双氰胺)制备,所得的氮化碳通常具有粒径大、水溶性差、发光性能弱等特点. 近年来,光响应性能增强的氮化碳纳米薄膜和氮化碳量子点的制备和应用受到越来越多研究者的关注[9-10]. Liu等[11]利用有机胺制备光致发光氮化碳量子点,将其作为新型类过氧化物酶,运用比色法检测H2O2和葡萄糖. Zhang等[12]采用水热合成法制备具有光氧化还原催化性能的富碳氮化碳纳米薄膜. 石墨相C3N4纳米片的制备及应用于生物成像、生物传感和离子检测也有相关报道[13-20]. Qiao等[21]报道了硒掺杂石墨氮化碳纳米薄膜的合成方法,并应用于过氧化氢和黄嘌呤比色法检测. Zheng等[22]报道了磁性氮化碳纳米片的简便合成及其在食用油样品中多环芳烃磁性固相萃取中的应用. 研究利用简单的方法合成具有不同形态的氮化碳纳米材料,拓展其应用领域是很有意义的工作.
氯(Cl2)、次氯酸(HClO)和次氯酸根离子(ClO−)具有强氧化性,常用作水的消毒剂. 水中溶解的Cl2、HClO和ClO−的总和定义为游离氯[23]. 游离氯在水中的残留浓度不宜过高,监测其在水中的含量很有必要. 游离氯的测定方法包括碘滴定法[24]、比色法[25]、化学发光法[26]、离子色谱法[27]、液相色谱法[28]、流动注射分析[29]等. 尽管每种方法都有其优点,但仍普遍存在检测灵敏度低、选择性差、使用有毒试剂或应用程序复杂等缺点,开发简便、有效和环保的游离氯测定方法显得很重要.
本研究应用简便的微波辅助溶剂热法,以柠檬酸和三聚氰胺为前驱体制备荧光氮化碳纳米材料(CNNPs),以CNNPs为荧光探针建立对游离氯的定量测定方法,并用于真实水样中游离氯的测定.
微波辅助法制备荧光氮化碳纳米材料及其在游离氯检测中的应用
Microwave-assisted preparation of fluorescent carbon nitride nanoparticles and their application in the detection of free chlorine
-
摘要: 在220 ℃下借助微波辅助溶剂热法,利用柠檬酸和三聚氰胺制备荧光氮化碳纳米材料(CNNPs),通过多种分析技术表征了制备的CNNPs。基于游离氯能快速猝灭CNNPs的荧光,将CNNPs做为荧光探针用于游离氯的定量测定,其荧光猝灭速度小于1 min;选择性响应实验和干扰实验表明该测定方法具有较好的灵敏度和选择性,游离氯的线性响应范围为0—80 μmol·L−1,检测限低至0.22 μmol·L−1。该方法适用于实际水样中游离氯的检测。Abstract: Fluorescent carbon nitride nanoparticles (CNNPs) were prepared from citric acid and melamine by a facile microwave-assisted solvothermal method at moderate reaction temperature (220 ℃). The obtained CNNPs were characterized by multiple analytical techniques. Free dissolved chlorine can quench the fluorescence of the CNNPs with excellent sensitivity and selectivity. The quenching speed was rather quick (less than 1 min), selective response experiments and interference experiments showed that this determination method had excellent sensitivity and selectivity. The linear response range of free chlorine was from 0 to 80 μmol·L−1. The limit of detection was as low as 0.22 μmol·L−1. We conclude that this method is applicable to detect free chlorine in real water samples.
-
Key words:
- carbon nitride nanoparticles /
- fluorescent quenching /
- free chlorine /
- melamine /
- citric acid
-
图 3 CNNPs-5的IR光谱(a),UV-Vis光谱和光致发光光谱(b),激发依赖发射光谱(c)(b)中插图分别是在日光(左)和365 nm紫外光(右)下拍摄的照片
Figure 3. The IR spectrum (a), UV-Vis and photoluminescence spectrum (b), and excitation-dependent emission spectrum (c) of the CNNPs-5. The two illustrations in (b) were photos taken under daylight (left) and 365 nm ultraviolet light (right).
表 1 不同方法检测ClO−的性能比较
Table 1. Comparison of performance of detecting ClO− by different methods
表 2 自来水样品中游离氯的测定
Table 2. Determination of free chlorine in tap water samples
样品
Samples添加量/(µmol·L−1)
Added总氯/(µmol·L−1)
Total found样品值/(µmol·L−1)
Found回收率/%
Recovery相对标准偏差/%
RSD1 0.1 1.21 1.12 96.3 3.40 0.5 1.62 100.6 3.10 1.0 2.10 97.6 1.61 2 0.1 1.20 1.09 107.5 2.70 0.5 1.61 103.4 3.70 1.0 2.06 96.8 2.05 -
[1] LIM SY, SHEN W, GAO Z. Carbon quantum dots and their applications [J]. Chemical Society Reviews, 2015, 44: 362-381. doi: 10.1039/C4CS00269E [2] 余致汐, 贺南南, 陈欢, 等. 甲壳素复合石墨相氮化碳的制备及光催化杀菌性能 [J]. 环境化学, 2020, 39(5): 1271-1278. doi: 10.7524/j.issn.0254-6108.2019081206 YU Z X, HE N N, CHEN H, et al. Preparation of chitin composite graphite phase carbonitride and its photocatalytic sterilization performance [J]. Environmental Chemistry, 2020, 39(5): 1271-1278(in Chinese). doi: 10.7524/j.issn.0254-6108.2019081206
[3] El-KHATIB A M, YOUSEFN S, GHATASS Z F, et al. Synthesized silver carbon nanotubes and zinc oxide nanoparticles and their ability to remove methylene blue dye [J]. Journal of Nanoneuroscience, 2019, 56: 1-16. [4] YUE L, LI H, SUN Q, et al. Red-Emissive ruthenium-containing carbon dots for bioimaging and photodynamic cancer therapy [J]. ACS Applied Nano Materials, 2020, 3: 869-876. [5] CHAMORRO-POSADA P, DANTE R C, VAZQUEZ-CABO J, et al. Experimental and theoretical investigations on a CVD grown thin film of polymeric carbon nitride and its structure [J]. Diamond and Related Materials, 2021, 111: 108169. doi: 10.1016/j.diamond.2020.108169 [6] LIU J, LIU Y, LIU N, et al. Metal-free efficient photocatalyst for stable visible water splitting via a two-electron pathway [J]. Science, 2015, 347: 970-974. doi: 10.1126/science.aaa3145 [7] ZHU J, XIAO P, LI H, et al. Graphitic carbon nitride: synthesis, properties, and applications in catalysis [J]. ACS Applied Materials & Interfaces, 2014, 6: 16449-16465. [8] 章家立, 李阳, 彭小明, 等. g-C3N4在水环境污染物去除和检测方面的应用研究进展 [J]. 华东交通大学学报, 2019, 36(1): 109-116. ZHANG J L, LI Y, PENG X M, et al. On applications of graphitic carbon nitride in pollutant removal and detection in water environment [J]. Journal of East China Jiaotong University, 2019, 36(1): 109-116(in Chinese).
[9] ZHANG J, CHEN Y, WANG X. Two-dimensional covalent carbon nitride nanosheets: synthesis, functionalization, and applications [J]. Energy & Environmental Science, 2015, 8: 3092-3108. [10] 马贺成, 刘建军, 于迎春, 等. 二维石墨相氮化碳纳米片的制备及其在光催化领域的研究进展 [J]. 应用化学, 2019, 36(3): 259-268. doi: 10.11944/j.issn.1000-0518.2019.03.180241 MA H C, LIU J J, YU Y C, et al. Research progress in preparation and photocatalysis of two-dimensional graphitic carbon nitride nanosheets [J]. Chinese Journal of Applied Chemistry, 2019, 36(3): 259-268(in Chinese). doi: 10.11944/j.issn.1000-0518.2019.03.180241
[11] LIU S, TIAN J, WANG L, et al. A general strategy for the production of photoluminescent carbon nitride dots from organic amines and their application as novel peroxidase-like catalysts for colorimetric detection of H2O2 and glucose [J]. RSC Advances, 2012, 2: 411-413. doi: 10.1039/C1RA00709B [12] ZHANG P, LI X, SHAO C, et al. Hydrothermal synthesis of carbon-rich graphitic carbon nitride nanosheets for photoredox catalysis [J]. Journal of Materials Chemistry A, 2015, 3: 3281-3284. doi: 10.1039/C5TA00202H [13] ASAITHAMBI S, SAKTHIVEL P, KARUPPAIAH M, et al. The bifunctional performance analysis of synthesized Ce doped SnO2/g-C3N4 composites for asymmetric supercapacitor and visible light photocatalytic applications [J]. Journal of Alloys and Compounds, 2021: 158807. [14] LIU Y, WANG Q, LEI J, et al. Anodic electrochemiluminescence of graphitic-phase C3N4 nanosheets for sensitive biosensing [J]. Talanta, 2014, 122: 130-134. doi: 10.1016/j.talanta.2014.01.018 [15] RONG M, LIN L, SONG X, et al. Fluorescence sensing of chromium(VI) and ascorbic acid using graphitic carbon nitride nanosheets as a fluorescent “switch” [J]. Biosensors & Bioelectronics, 2015, 68: 210-217. [16] 陈珠灵, 林敏秀, 宋志平, 等. 基于石墨相氮化碳量子点直接荧光猝灭法检测碘离子的研究 [J]. 光谱学与光谱分析, 2019, 39(7): 2029-2033. CHEN Z L, LIN M X, SONG Z P, et al. Study of direct fluorescencence quenching of graphitic carbon nitride for the detection of iodine ions [J]. Spectroscopy and Spectral Analysis, 2019, 39(7): 2029-2033(in Chinese).
[17] ZHANG H, HUANG Y, HU S, et al. Fluorescent probes for “off-on” sensitive and selective detection of mercury ions and L-cysteine based on graphitic carbon nitride nanosheets [J]. Journal of Materials Chemistry C, 2015, 3: 2093-2100. doi: 10.1039/C4TC02394C [18] ABDOLMOHAMMAD-ZADEH H, RAHIMPOUR E. A novel chemosensor based on graphitic carbon nitride quantum dots and potassium ferricyanidechemiluminescence system for Hg(Ⅱ) ion detection [J]. Sensors and Actuators B: Chemical, 2016, 225: 258-266. doi: 10.1016/j.snb.2015.11.052 [19] HAN J, ZOU HY, GAO MX, et al. A graphitic carbon nitride based fluorescence resonance energy transfer detection of riboflavin [J]. Talanta, 2016, 148: 279-284. doi: 10.1016/j.talanta.2015.10.038 [20] XIE H, DONG J, DUAN J, et al. Magnetic nanoparticles-based immunoassay for aflatoxin B1 using porous g-C3N4 nanosheets as fluorescence probes [J]. Sensors and Actuators B:Chemical, 2019, 278: 147-152. doi: 10.1016/j.snb.2018.09.089 [21] QIAO F, WANG J, AI S, et al. As a new peroxidase mimetics: The synthesis of selenium doped graphitic carbon nitride nanosheets and applications on colorimetric detection of H2O2 and xanthine [J]. Sensors and Actuators B: Chemical, 2015, 216: 418-427. doi: 10.1016/j.snb.2015.04.074 [22] ZHENG H B, DING J, ZHENG S J, et al. Facile synthesis of magnetic carbon nitride nanosheets and its application in magnetic solid phase extraction for polycyclic aromatic hydrocarbons in edible oil samples [J]. Talanta, 2016, 148: 46-53. doi: 10.1016/j.talanta.2015.10.059 [23] DONG Y, LI G, ZHOU N, et al. Graphene quantum dots as a green and facile sensor for free chlorine in drinking water [J]. Analytical Chemistry, 2012, 84: 8378-8382. doi: 10.1021/ac301945z [24] ZHOU M, LI T, ZU M, et al. Membrane-based colorimetric flow-injection system for online free chlorine monitoring in drinking water [J]. Sensors and Actuators B:Chemical, 2021, 327: 128905. doi: 10.1016/j.snb.2020.128905 [25] MA Z, CHEN X, WANG C, et al. A novel ratiometric fluorescence probe for hypochlorite detection and its application in cell imaging [J]. Journal of Molecular Structure, 2020, 1221: 128812. doi: 10.1016/j.molstruc.2020.128812 [26] CLAVER J B, MIRON M C V, CAPITAN-VALLVEY L F. Determination of hypochlorite in water using a chemiluminescent test strip [J]. Analytica Chimica Acta, 2004, 522: 267-273. doi: 10.1016/j.aca.2004.06.051 [27] CHEN P, WEI W Z, YAO S Z. Different valency chlorine species analysis by non-suppressed ion-chromatography with double cell quartz crystal detector [J]. Talanta, 1999, 49: 571-576. doi: 10.1016/S0039-9140(99)00041-7 [28] WATANABE T, IDEHARA T, YOSHIMURA Y, et al. Simultaneous determination of chlorine dioxide and hypochlorite in water by high-performance liquid chromatography [J]. Journal of Chromatography A, 1998, 796: 397-400. doi: 10.1016/S0021-9673(97)01009-1 [29] POBOZY E, PYRZYNSKA K, SZOSTEK B, et al. Flow-injection spectrophotometric determination of free residual chlorine in waters with 3, 3′-dimethylnaphtidine [J]. Microchemical Journal, 1995, 51: 379-86. doi: 10.1006/mchj.1995.1044 [30] ZHOU J, YANG Y, ZHANG C. A low-temperature solid-phase method to synthesize highly fluorescent carbon nitride dots with tunable emission [J]. Chemical Communications, 2013, 49: 8605-8607. doi: 10.1039/c3cc42266f [31] LIN L, RONG M, LU S, et al. A facile synthesis of highly luminescent nitrogen-doped graphene quantum dots for the detection of 2, 4, 6-trinitrophenol in aqueous solution [J]. Nanoscale, 2015, 7: 1872-1878. doi: 10.1039/C4NR06365A [32] CAO X, MA J, LIN Y, et al. A facile microwave-assisted fabrication of fluorescent carbon nitride quantum dots and their application in the detection of mercury ions [J]. Spectrochimica Acta Part A, 2015, 151: 875-880. doi: 10.1016/j.saa.2015.07.034 [33] ANIKUMAR P, WANG X, CAO L, et al. Toward quantitatively fluorescent carbon-based “quantum” dots [J]. Nanoscale, 2011, 3: 2023-2027. doi: 10.1039/c0nr00962h [34] MESSINA F, SCIORTINO L, POPESCU R, et al. Fluorescent nitrogen-rich carbon nanodots with an unexpected β-C3N4 nanocrystallinestructure [J]. Journal of Materials Chemistry C, 2016, 4: 2598-2605. doi: 10.1039/C5TC04096E [35] LIU J, SHANGGUAN M, ZENG X, et al. Phosphorescent iridium (Ⅲ) complex for efficient sensing of hypochlorite and imaging in living cells [J]. Analytical Biochemistry, 2020, 592: 113573. doi: 10.1016/j.ab.2019.113573 [36] SHIRAISHI Y, YAMADA C, TAKAGI S, et al. Fluorometric and colorimetric detection of hypochlorous acid and hypochlorite by a naphthalimide–dicyanoisophorone conjugate [J]. Journal of Photochemistry and Photobiology A:Chemistry, 2021, 406: 112997. doi: 10.1016/j.jphotochem.2020.112997 [37] NING Y, CUI J, LU Y, et al. De novo design and synthesis of a novel colorimetric fluorescent probe based on naphthalenone scaffold for selective detection of hypochlorite and its application in living cells [J]. Sensors and Actuators B:Chemical, 2018, 269: 322-330. [38] WU H, ZHANG W, WU Y, et al. A 7-diethylaminocoumarin-based chemosensor with barbituric acid for hypochlorite and hydrazine [J]. Microchemical Journal, 2020, 159: 105461. doi: 10.1016/j.microc.2020.105461 [39] ZHANG Y M, FANG H, ZHU W, et al. Ratiometric fluorescent sensor based oxazolo-phenazine derivatives for detect hypochlorite via oxidation reaction and its application in environmental samples [J]. Dyes and Pigments, 2020, 172: 107765. doi: 10.1016/j.dyepig.2019.107765 [40] RHA C J, LEE H, KIM C. Development of an azo-naphthol-based probe for detecting hypochlorite (ClO−) via color change in aqueous solution [J]. Inorganic Chemistry Communications, 2020, 121: 108244. doi: 10.1016/j.inoche.2020.108244 [41] WANG H, ZHANG L, GUO X, et al. Comparative study of Cl, N-Cdots and N-Cdots and application for trinitrophenol and ClO− sensor and cell-imaging [J]. Analytica Chimica Acta, 2019, 1091: 76-87. doi: 10.1016/j.aca.2019.09.019