碳量子点光催化
碳量子点的光催化
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Materials Chemistry A
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Aneeya K. Samantara,ab Subash Chandra Sahu,ab Arnab Ghoshc and Bikash Kumar Jena*ab
Here, a hybrid material composed of sandwiched reduced graphene oxide (rGO) and N,S co-doped carbon quantum dots (N,S-CQDs) was prepared following a facile synthetic route. This metal-free composite has demonstrated their dual performance as an electrode material for supercapacitors and fuel cell catalysts. It shows robust cyclic stability with high energy and power density without any binders. The enhanced activity of the composite can be ascribed to the CQDs present within the interlayer of the rGO which enhance the accessibility of the charged ions and increase the capacitance of the composite. In addition, the electrocatalytic activity of the composite has been assessed as a metal-free cathode catalyst towards the oxygen reduction reaction (ORR) for fuel cell applications. It shows better performance in terms of high reduction potential and high reduction current as compared to rGO. This can be ascribed to the
cds碳量子点
CDS碳量子点概述CDS碳量子点是一种新型的碳基材料，具有优异的光电性能和潜在的应用前景。
碳量子点（Carbon Dots，简称CQDs）是一类尺寸小于10纳米的碳纳米材料，具有许多独特的特性，如荧光、电化学和光电性能等。
CDS碳量子点是由硫化碳（Carbon Disulfide）合成的碳量子点，其在荧光材料、生物成像、光电子器件等领域具有广泛的应用前景。
合成方法CDS碳量子点的合成方法多种多样，常见的方法包括溶剂热法、微波法、水热法等。
下面以水热法为例，介绍CDS碳量子点的合成过程：1.准备硫化碳溶液：将硫化碳溶解在适量的溶剂中，如水或有机溶剂。
溶液中的硫化碳浓度越高，合成的CDS碳量子点的荧光强度越高。
2.加热反应：将硫化碳溶液加热至一定温度，常见的反应温度为100-200摄氏度。
加热的过程中，溶液中的硫化碳会发生裂解和聚合反应，生成碳量子点。
3.调控反应条件：在反应过程中，可以通过调节温度、反应时间、溶剂种类等参数来控制CDS碳量子点的大小、形状和荧光性能。
4.分离和纯化：将反应溶液中的CDS碳量子点通过离心、过滤等方法分离出来，并用纯溶剂进行洗涤和纯化，去除杂质。
5.表征分析：通过透射电子显微镜（TEM）、紫外-可见吸收光谱（UV-Vis）、荧光光谱等技术对合成的CDS碳量子点进行表征和分析，确定其大小、形状、结构和荧光性能等。
特性与应用CDS碳量子点具有以下几个重要的特性和应用潜力：1. 荧光性能CDS碳量子点具有宽波长荧光发射特性，其发射峰位于可见光区域。
荧光强度和发射峰可以通过调节合成条件来实现。
CDS碳量子点在荧光探针、生物成像、光电子器件等领域具有广泛的应用前景。
2. 生物兼容性CDS碳量子点具有优异的生物兼容性，可以在生物体内进行成像和治疗。
由于其尺寸小、荧光性能好、毒性低等特点，CDS碳量子点在生物医学领域具有重要的应用潜力，如生物成像、药物传递、癌症治疗等。
3. 光电子器件CDS碳量子点在光电子器件中可以作为荧光材料、光电转换材料等。
碳量子点光催化
Enhanced Photocatalytic Activity of the Carbon Quantum Dot-Modified BiOI MicrosphereYuan Chen 1,2,Qiuju Lu 1,Xuelian Yan 1,2,Qionghua Mo 1,3,Yun Chen 1,Bitao Liu 1*,Liumei Teng 1,Wei Xiao 1,Liangsheng Ge 1and Qinyi Wang 4BackgroundThe exploration and construction of new photocatalysts with high catalytic efficiency in sunlight is a core issue in photocatalysis all the time and is also significant in solv-ing current environment and energy problems [1–3].Recently,bismuth oxyhalides (BiOX,X =Cl,Br,and I)as a novel ternary oxide semiconductor have drawn much attention because of their potential application in photo-catalysis.Among them,BiOI is photochemically stable and has the smallest band gap (about 1.7–1.9eV),which can be activated by visible light irradiation [4–6].How-ever,the narrow band gap could also lead to a quick re-combination of the photogenerated electron –hole pairs.Hence,inhibiting the recombination of the photogener-ated electron –hole pairs was the key point to enhance the photocatalytic property.Carbon quantum dot (CQD),as a novel issue of re-cently found nanocarbons,exhibits excellent photophysi-cal properties.Especially,the strong size and excitation wavelength-dependent photoluminescence (PL)behav-iors would enhance the photocatalytic properties of theCQD-based composites [7,8].Previous studies have shown that the electron-accepting and transport properties of car-bon nanomaterials provide a convenient way to separate photogenerated electrons;thus,enhanced photocatalytic performance can be achieved through the construction of semiconductor/carbon composites [9,10].Notably,the design of complex photocatalysts (TiO 2/CQDs,Ag 3PO 4/CQDs,Bi 2MoO 6/CQDs)to utilize more sun-light has been reported [11–13].Considering such re-markable properties of CQDs and the limitations of the BiOI photocatalytic system,the combination of CQDs and BiOI may be regarded as an ideal strategy to con-struct highly efficient complex photocatalytic systems.In this work,we prepared a CQD/BiOI nanocomposite photocatalyst via a facile hydrothermal process.The re-sults indicated that the CQDs were successfully com-bined with the BiOI microsphere and the introduction of CQDs could efficiently increase the concentration and the migration ratio of the photogenerated carrier,which was the key for the increased photocatalytic property.MethodsReagentsAll chemicals used in this study were of analytical grade (ChengDu Kelong Chemical Co.)and were used without*Correspondence:liubitao007@ 1Research Institute for New Materials Technology,Chongqing University of Arts and Sciences,Yongchuan,Chongqing 402160,ChinaFull list of author information is available at the end of the article©2016Chen et al.Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0International License (/licenses/by/4.0/),which permits unrestricted use,distribution,andreproduction in any medium,provided you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons license,and indicate if changes were made.Chen et al.Nanoscale Research Letters (2016) 11:60 DOI 10.1186/s11671-016-1262-7further purification.Citric acid(C6H8O7·H2O,99.5%), ethylenediamine(C2H8N2,99%),Bi(NO3)3·5H2O(99%), KI(99%),ethylene glycol(C2H6O2,99.5%),ethanol (C2H6O,99.7%),and distilled water were used in all experiments.Synthesis of CQD-Modified BiOICQD powder was synthesized according to the literature followed by freeze drying[14].BiOI microspheres were synthesized by a facile solvothermal method.Typically, 0.4g KI and1.16g Bi(NO3)3·5H2O were dissolved in 40mL of ethylene glycol.Then,a certain content of CQD powder was added into the solution.Subsequently, the mixture was transferred to a50-mL Teflon-lined stainless steel autoclave and the reaction was kept at 160°C for12h.Finally,the resulting precipitate was col-lected,washed thoroughly with deionized water and ethanol,and dried at60°C in vacuum.Pure BiOI and CQD-modified BiOI samples with different mass ratios (0.5,1,1.5,and2wt.%)were synthesized using a similar route by tuning the content of CQDs.InstrumentsThe X-ray diffraction(XRD)patterns of the samples were recorded on a Danton TD-3500X-ray diffractometer using Cu Kαradiation(λ=1.54Å).The field-emission scanning electron microscopy(FE-SEM)measurements were carried out with a field-emission scanning electron microscope(Hitachi,SU-8020).Transmission electron microscopy(TEM)micrographs were taken with a JEOL-JEM-2010(JEOL,Japan)operated at200kV. Fourier transform infrared(FT-IR)spectra(KBr pellets) were recorded on Nicolet model Nexus470FT-IR equip-ment.X-ray photoelectron spectroscopy(XPS)analysis was performed on an ESCA Lab MKII X-ray photoelec-tron spectrometer using the Mg Kαradiation.UV-vis ab-sorption spectra of the samples were obtained on a UV-vis spectrophotometer(Hitachi,U-3900),and BaSO4powder was used as the substrate.The PL spectra were measured using a customized single-photon counting system (Beijing Zolix),A He-Ga laser(λ=325nm)was used as the excitation source.The photoelectric performance was measured using an electrochemical system(CHI-660B, China).BiOI and CQD/BiOI electrodes served as the working electrode;the counter and the reference elec-trodes were a platinum wire and a saturated Ag/AgCl electrode,respectively.A solution of0.1M NaSO4 was used as an electrolyte solution for the measure-ment,and a150-W Xe arc lamp was utilized as the light source for the photoelectrochemical(PEC)meas-urement.The photoresponse of the photocatalysts in the presence and absence of visible light was mea-sured at0.0V.Electrochemical impedance spectra (EIS)were recorded in the open circuit potential mode,and the frequency was ranged from100kHz to0.01Hz.Trapping ExperimentPotassium iodide(KI),tertbutyl alcohol(TBA),and po-tassium dichromate(K2Cr2O7)were used to trap hole,·OH,and photogenerated electrons,respectively.Photo-catalyst(0.1g)with different trapping agents was added into MO(100mL,50mg/L)aqueous solution.The scav-engers used in this research are tertbutyl alcohol(TBA, 1%)for·OH,potassium dichromate(K2Cr2O7,1%)for e−,and potassium iodide(KI,1%)for h+,respectively. Photocatalytic Activity MeasurementThe photocatalytic activities of the as-prepared samples were evaluated by the degradation of methyl orange(MO) under visible light irradiation at ambient temperature using a150-W Xe lamp with a420-nm cutoff filter as the light source.In each experiment,100mg of photocatalyst was dispersed in an MO(100mL,50mg L−1)aqueous so-lution.Prior to irradiation,the solution was continuously stirred in the dark for1h to ensure the establishment of adsorption–desorption equilibrium between the photo-catalysts and the degrading pollutants.During the pho-toreactions,the MO solutions with photocatalysts were continuously stirred with magnetometric stirrer,and a 3-mL sample solution was taken out at every10-min interval during the experiment,followed by centrifuga-tion and filtration to remove the photocatalysts.The concentrations of MO were determined by monitoring the change of optical density at465nm,with a Varian UV-vis spectrophotometer(Cary-50,Varian Co.). Results and DiscussionThe morphology of the as-prepared CQD/BiOI compos-ites was shown in Fig.1a,b.As seen,the sample was composed of uniform layered structure nanoplates and presented microsphere morphology.The diameter was about1to2μm and the thickness of the nanoplates was less than50nm.The SEM images of the other series samples were also given in Additional file1:Figure S1, and it can be seen that the adding of CQDs would not change the original morphologies of BiOI.The nitrogen adsorption–desorption isotherms and the corresponding pore size distributions of the as-obtained samples were shown in Fig.1c.According to the result,the calculated specific surface area was42m2/g.Obviously,this large specific surface area could have a positive effect on photocatalytic property[15,16].The XRD patterns of the series of CQD/BiOI compos-ites were shown in Fig.1d.It can be clearly seen that these photocatalysts were crystallized in a single phase.All the samples can be indexed to the tetragonal structure BiOI (JCPDS10-0445).However,for the CQD-modified BiOIsamples,no characteristic peak of CQDs(about26°) can be found,which should be attributed to the low CQD content in the samples.Actually,if the content was lower than5%,which was hardly characterized by XRD,similar work was also demonstrated in the previous report[12,17].For a further investigation,the TEM and HRTEM were shown in Fig.2a, b.Obviously,the nanoplates and microsphere morphology can be found in Fig.2a, which was in agreement with the SEM result before. The high-resolution image was shown in Fig.2b. Clearly,many uniformed particles were distributed on the surface of the BiOI;and in the corresponding HRTEM image,it can be seen that these particles have distinct lattice spacing.An atomic spacing (0.332nm)could be distinguished,which could be ascribed to the(002)lattice fringes of CQD.The TEM and HRTEM results were directly indicated that the CQDs were successfully modified on the BiOI microsphere.FT-IR spectra were also carried out to further characterization of CQD/BiOI(Fig.2c).The absorption band at1624cm−1should assign to the stretching modes of BiOI[12].The absorption band was located at 1384cm−1which should be attributed to the stretching modes of NO3−groups and C=C[18],and the band at 1046and880cm−1was associated with the skeletal vi-bration of sp2and sp3C–H and C–OH[12].Obviously, due to the existence of CQDs,the bond was largely enhanced,which further demonstrated the existence of CQDs in these composites.XPS spectrum was also used to study the surface properties of the CQD-modified BiOI sample as shown in Fig.2d.It can be seen that C peaks were at 284.7,286,and288.3eV,which could be assigned to the C–C bond with the sp2orbital,C–O–C bond, and C=O bond,respectively[19].As for the O1s (Additional file1:Figure S2a shown),two peaks lo-cated at530.8and531.4eV also should be ascribed to the C–O–C and C=O bond in CQDs,respectively. The Bi4f and I3d also were shown in Additional file1: Figure S2b,c,both of which were consistent with the re-ported[18,20].Before the photodegradation process,the adsorption–desorption property was tested during60min and the result was given in Additional file1:Figure S3.It can be seen that all the samples shown excellent adsorption ability,which should be attributed to the huge specific surface areas of BiOI.This adsorption ability was en-hanced with the CQD content increased,which should ascribe to the surface electron accumulated in CQDs [21].The photocatalytic activities were evaluated as shown in Fig.3a.Clearly,all the CQD-modified BiOI samples exhibited higher photocatalytic activity than pure BiOI,and the photocatalytic efficiency was 1.5wt.%>2wt.%>1wt.%>0.5wt.%>pure BiOI.For the1.5wt.%sample,it can degrade98%of MO in 50min while there is only40%of the pure BiOIimages(a,b)and nitrogen adsorption–desorption isotherms.Insert:the corresponding pore size distributions XRD patterns of the series of CQD/BiOI composites(d)images of CQD/BiOI1.5wt.%sample(a,b).FT-IR spectra of pure BiOI and CQD/BiOI1.5wt.%samples(c).thewt.%samples(d)Photocatalytic degradation of MO in the presence of pure BiOI and CQDs/BiOI materials under visible light(λ>420) reflectance spectroscopy of the pure BiOI and the series of CQD/BiOI samples(b).Transient photocurrent electrochemical impedance spectroscopy(EIS)Nyquist plot(d)of the series samplessample.The CQDs would act as an electron-accepting and transport center,which would result in a lower re-combination rate of photoinduced electron–hole pairs. The light absorption and the charge transportation and separation were the key properties of the high per-formance of CQD/BiOI photocatalyst.UV-vis spectros-copy has been proved for understanding the electronic structure of semiconductors.As can be seen in Fig.3b, the pure BiOI sample could absorb the wavelength less than750nm which indicate a strong light absorption and the result was in accordance with the previous report[4,5].Meanwhile,for the CQD-modified samples, the absorption intensity increased with the CQD content increase.The increased light absorption may generate more electron–hole pairs during the photocatalytic process.As well known,the charge separation is the most com-plex and key factor essentially determining the efficiency of photocatalysis[22].For a deep investigation,the PEC system was accompanied to investigate the photophysi-cal behaviors of photogenerated electron–hole pairs as shown in Fig.3c.It was found that the photocurrent re-sponse of all CQD/BiOI samples were higher than the pure BiOI sample,especially.As shown,the CQD/BiOI 1.5wt.%sample was nearly seven times higher than the pure BiOI.The result suggested a more efficient separ-ation and longer lifetimes of photoexcited electron–hole pairs.The EIS result(shown in Fig.3d)reflected that the impedance arc radius of CQD/BiOI was smaller than the pure BiOI under visible light,indicating an enhanced separation efficiency of the photoexcited charge carriers in CQD/BiOI.In this regard,the transient photocurrent response and EIS results revealed an analogous trend with respect to the photocatalytic activity of the sam-ples.Furthermore,the PL result also indicated that the CQD-modified BiOI could effectively decrease the recombination of the photoinduced electrons and holes (as seen in Additional file1:Figure S4).To determine the involvement of active radical species during photocatalysis,we performed a trapping experi-ment(Fig.4a)for the detection of the hydroxyl radical (·OH),hole(h+),and electron(e−)in the photocatalytic process,taking the CQD/BiOI1.5wt.%sample as an example.The degradation behavior of MO is decreased upon the addition of TBA,K2Cr2O7,and KI,respectively, validating that·OH radicals,photoexcited electrons, and h+are the main active species for MO removal. Based on the above results,the reaction mechanism diagram of CQD/BiOI photocatalysts was proposed as shown in Fig.4b.The band gap of BiOI was about 1.8eV,which can be easily excited by visible light. However,the E CB and E VB of BiOI were0.6and 2.4eV,respectively.Hence,·OH could not be pro-duced via an e−→·O2−→H2O2→·OH route.For thePhotocatalytic activity comparison of the CQD/BiOI1.5wt.%sample in different photocatalysis systems under visible light the separation and transfer of photogenerated charges in the CQD/BiOI combined with the possible reaction procedure(b).Stability tests of CQD/BiOI1.5wt.%sample(c)and the XRD pattern of the sample before and afterVB holes in BiOI,it can oxidize OH −or H 2O into ·OH due to their high potential energy;thus,it can be concluded that ·OH should be generated only via an h +→OH −/H 2O →·OH route [18].Furthermore,the photogenerated electrons would transfer to the CQDs due to their excellent electronic conductivity,which resulted in effective separation process for the photogenerated electron –hole pairs.The transferred electrons will accumulate on the CQDs and then in-hibit the recombination of the electron –hole pairs.Obviously,the enhanced photocatalytic activity can be achieved,and the CQDs would play a crucial role in this process.The photochemical and structural stability of a catalyst is important for practical applications.The stability of CQD/BiOI was tested by carrying out the photocatalytic reaction for multiple runs.The results were presented in Fig.4c.The photocatalytic activity during the sixth runs can be observed.This result demonstrated that the CQD/BiOI composites have a stable photochem-ical property.Moreover,the almost unchanged XRD spectra of CQD/BiOI before and after the stability test (Fig.4d)further indicated the phase stability of the CQD-modified BiOI photocatalysts.ConclusionsIn conclusion,CQD-modified BiOI photocatalysts were synthesized using a facile hydrothermal treatment process.After being modified by CQDs,the photocatalytic activ-ities of degradation of MO under visible light irradiation were increased greatly.The significant improvement in photocatalytic performance was attributed to the crucial role of CQDs in the samples.The CQD modification has several advantages,including enhanced light harvesting,improvement of interfacial charge transfer,and suppres-sion of charge recombination.This work provides useful information on the design and fabrication of other CQD-modified semiconductor materials.Additional FileCompeting InterestsThe authors declare that they have no competing interests.Authors ’ContributionsYC designed the experiment and wrote the paper.QL,YC,and XYcompleted the synthesis of the samples.MQ and LT carried out the series characterization of the nanocomposites.BL and WX did the analysis of the data.GL and WQ gave some revision for the grammar of the manuscript.All authors read and approved the final manuscript.AcknowledgementsThis work was supported financially by the National Natural ScienceFoundation of China (21401015),the Basic and Frontier Research Program ofChongqing Municipality (cstc2014jcyjA50012and cstc2013jcyjA20023),Scientific and Technological Research Program of Chongqing Municipal Education Commission (KJ1401111and KJ1501104),Yongchuan NaturalScience Foundation (Ycstc2014nc3001and Ycstc2014nc4001),Local Colleges and Universities National College Students Innovation and Entrepreneurship Training Program (201410642001),and Foundation of Chongqing University of Arts and Sciences (Y2014CJ27and R2013CJ05).Author details 1Research Institute for New Materials Technology,Chongqing University of Arts and Sciences,Yongchuan,Chongqing 402160,China.2School of Materials Science and Engineering,Chongqing University of Technology,Banan,Chongqing 400054,China.3Faculty of Materials and Energy,Southwest University,Beibei,Chongqing 400715,China.4Department of Chemical Engineering,University of Missouri,Columbia,MO 65211-2200,USA.Received:29October 2015Accepted:14January2016References1.Fujishima A,Honda K (1972)Electrochemical photolysis of water at asemiconductor electrode.Nature 238:37–382.Wen Y,Liu BT,Zeng W,Wang YH 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碳量子点综述
碳量子点综述胡东旭 2014级环境工程卓越班 201475050112摘要:碳量子点(CQDs, C-dots or CDs)是一种新型的碳纳米材料，尺寸在10 nm以下，具有良好的水溶性、化学惰性、低毒性、易于功能化和抗光漂白性、光稳定性等优异性能，是碳纳米家族中的一颗闪亮的明星。
最近几年的研究报道了各种方法制备的CQDs在生物医学、光催化、光电子、传感等领域中都有重要的应用价值。
这篇综述主要总结了关于CQDs的最近的发展，介绍了CQDs的合成方法、物理化学性质以及在生物医学、光催化、环境检测等领域的应用。
1 引言在过去的20年间，鉴于量子点特殊的性质，尤其是量子点相对于有机染料而言，容易调节的光学性质和抗光降解性质，使量子点得到了广泛的关注。
如果量子点可以克服造价昂贵、合成条件严格和众所周知的高毒性等缺点，则有望广泛地应用于生物传感和上物成像领域。
最近几年，量子点的研究非常活跃，尤其是关于它在生物和医学中的应用。
量子点一般是从铅、镉和硅的混合物中提取出来的，但是这些材料一般有毒，对环境也有危害。
所以科学家们开始在一些良性化合物中提取量子点。
因此，很多的研究均围绕着合成毒性更低的其它材料量子点来进行，这些替代材料的碳量子点，如硅纳米粒子、碳量子点均具有优异的光学性质。
相对金属量子点而言，碳量子点无毒害作用，对环境的危害很小，制备成本低廉。
它的研究代表了发光纳米粒子研究进入了一个新的阶段。
2 碳量子点的合成大多数的碳量子点主要是由无定形的碳到晶化的碳核组成的以sp2杂化为主的碳，碳量子点的晶格间距和石墨碳或者无定形层状碳的结构一致。
如果没有其他修饰试剂的修饰碳量子点表面会含有一些含氧基团，而含氧基团的多少和种类与实验条件相关。
发光碳量子点的合成方法可以分为两大类（图一），化学法和物理法。
图一碳量子点的制备方法2.1化学法2.1.1电化学法Zhou利用离子液体辅助电解高纯石墨棒和高温热解纯定向石墨(HOPG)于离子液体和水溶液中，通过控制离子了液体中水的含量得到不同荧光性质的荧光纳米粒子、纳米带、石墨等产物。
二氧化钛碳量子点光催化附件
Supporting Information Scalable synthesis of TiO2/graphene nanostructured composite with high rate performance for lithium ion batteriesXing Xin, Xufeng Zhou*, Jinghua Wu, Xiayin Yao and Zhaoping Liu*Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, 315201, P. R. China E-mail: liuzp@ & zhouxf@Experimental details of GO preparation 6.0 g of KNO3 and 6.0 g of natural graphite (300 mesh) were added to 270 cm3 of concentrated H2SO4 (98wt.%) at room temperature, and stirred for 10 minutes before slowly adding 36 g of KMnO4 into the mixture. The above mixture was then heatedto 40°C and stirred for 6 hrs. Subsequently, under vigorous stirring, 480 cm3 of water was rapidly added, causing a quick rise in temperature to ~60°C. After, the slurry was continuously stirred at this temperature for another 30 minutes before 1200 cm3 of water and 36 cm3 of H2O2 solution (30wt.%) were added sequentially to dissolve insoluble manganese species. Finally, the resulting graphite oxide suspension was washed repeatedly in water until the solution pH reached a constant value of ~5.0. The graphite oxide became partially delaminated during washing. We assured the complete delamination of graphite oxide into GO by more mechanical stirring and ultrasonic treatment.1Figure S1. XRD pattern of HTO.Figure S2. TEM images of the intermediate products sampled every 5 minutes (a-g) during the dropwise addition of TBT in the synthesis of f-HTO/GO, and TEM image of the sample after aging for 3 hours (h).2Figure S3. SEM and TEM images of f-HTO/GO samples with different weight ratios of GO/TBT=1/50 (a and f), 1.5/50 (b and g), 2/50 (c and h), 2.5/50 (d and i) and 3/50 (e and j).Figure S4. XRD patterns of p-TiO2, f-TiO2 and f-TiO2-G, which can all be indexed to the diffraction of pure anatase phase.3Figure S5. SEM images of (a) p-TiO2, (b) f-TiO2, and (c-g) f-TiO2/G synthesized with different weight ratios of GO/TBT=1/50 (c), 1.5/50 (d), 2/50 (e), 2.5/50 (f) and 3/50 (g). (h) TGA curves of f-TiO2/G nanocomposites synthesized with different weight ratios of GO/TBT.4Figure S6. Cyclic voltammetry profiles of the f-TiO2/G nanocomposites measured at different scan rates.Figure S7. Rate performance of f-TiO2/G nanocomposites with different graphene contents.5。
碳量子点(cqds) 石墨炔量子点
碳量子点(cqds)是一种具有纳米尺度的碳基材料，具有优异的光电性能和化学稳定性，近年来受到了广泛关注。
其中，石墨炔量子点作为一种特殊的碳量子点，在光催化、光电器件、生物成像等领域展现出了巨大的应用潜力。
本文将从以下几个方面详细介绍碳量子点和石墨炔量子点的相关研究进展。
一、碳量子点的制备方法碳量子点的制备方法包括化学氧化方法、电化学法、微波辐射法、激光剥离法、等离子体法等多种途径。
其中，化学氧化方法是最为常见的制备方法之一，通过碳前体的酸碱处理、氧化剥离等步骤，可制备出具有一定量子效应的碳量子点。
二、石墨炔量子点的结构与性质石墨炔量子点具有类似于石墨炔结构的碳原子排列，拥有较小的带隙、较高的导电性和光催化活性。
石墨炔结构的引入使得石墨炔量子点在光电器件中表现出了良好的性能，同时在生物成像领域也表现出了巨大的潜力。
三、碳量子点在光催化中的应用碳量子点作为一种优异的光催化剂，可用于水分解、二氧化碳还原、有机污染物降解等反应。
石墨炔量子点在光催化中的应用研究表明，其具有较高的光催化活性和稳定性，为光催化反应的高效进行提供了可能。
四、石墨炔量子点在生物成像中的应用石墨炔量子点具有较好的生物相容性和荧光性能，被广泛应用于生物成像领域。
其在细胞标记、组织成像、药物传递等方面的应用研究成果丰硕，为生物医学领域的发展带来了新的机遇和挑战。
五、碳量子点的应用前景碳量子点及其衍生物在光电器件、生物成像、光催化等领域的广泛应用展现出了巨大的潜力，但也面临着制备方法简单化、性能稳定化、应用系统化等方面的挑战。
未来的研究方向将集中在碳量子点的制备与改性、性能调控与机制解析、应用拓展与产业化等方面，以期为碳量子点的应用提供更为坚实的基础和保障。
碳量子点和石墨炔量子点作为当前领域的研究热点，其在光电器件、生物成像、光催化等领域的应用前景广阔，但仍需加大基础研究和工程应用方面的投入，以推动碳量子点在相关领域的深入应用与开发。
希望本文的内容能为相关研究和应用工作提供一定的参考和借鉴，期待碳量子点在未来能够迎来更加灿烂的发展。
研究方向 碳量子点 催化和生物医学
碳量子点是一种新型纳米材料，在催化和生物医学领域具有广泛的应用前景。
本文将从碳量子点的结构特征、催化应用和生物医学应用三个方面进行阐述。
一、碳量子点的结构特征碳量子点是一种直径在1纳米以下的碳基纳米材料，具有优异的光电性能和生物相容性。
其结构特征包括：1. 大小均一：碳量子点的直径一般在1纳米左右，具有较高的大小均一性；2. 量子尺寸效应：由于其尺寸小于激子束缚半径，因此呈现出量子尺寸效应，表现出特殊的光电性能；3. 表面官能团：碳量子点表面富含羟基、羰基等官能团，使其具有良好的分散性和生物相容性。
二、碳量子点在催化应用中的研究进展碳量子点在催化领域具有广泛的应用前景，主要体现在以下几个方面：1. 电催化剂：碳量子点通过调控其能带结构和表面官能团，可用作氧还原、析氢和二氧化碳还原等电催化反应的催化剂；2. 光催化剂：利用碳量子点的光电性能，可构建光催化体系，实现光解水、光催化CO2还原等反应；3. 催化剂载体：碳量子点表面富含官能团，具有良好的活性位点，可用作金属纳米粒子的载体，提高其在催化反应中的稳定性和活性。
三、碳量子点在生物医学应用中的研究进展碳量子点在生物医学领域具有诸多应用，包括：1. 生物成像：碳量子点由于其较好的荧光性能和生物相容性，可用于细胞成像、组织成像等生物成像领域；2. 肿瘤治疗：碳量子点可通过光热和光动力等方式对肿瘤进行治疗，具有较好的治疗效果和生物安全性；3. 药物传输：利用碳量子点的荧光特性和载药功能，可实现药物的靶向输送和释放，提高药物的疗效和减轻副作用。
碳量子点作为新型纳米材料，在催化和生物医学领域具有广泛的应用前景。
随着对其结构特征和性能的深入研究，相信碳量子点将在未来得到更广泛的应用和发展。
（扩写部分）四、碳量子点在催化应用中的新进展除了上文提及的催化应用，碳量子点在催化领域还有一些新的应用和研究进展：1. 电催化剂：近年来，研究人员不断探索碳量子点在氧气电还原反应（ORR）中的应用。
碳量子点综述
碳量子点综述胡东旭 2014级环境工程卓越班 201475050112摘要:碳量子点(CQDs, C-dots or CDs)是一种新型的碳纳米材料，尺寸在10 nm以下，具有良好的水溶性、化学惰性、低毒性、易于功能化和抗光漂白性、光稳定性等优异性能，是碳纳米家族中的一颗闪亮的明星。
最近几年的研究报道了各种方法制备的CQDs在生物医学、光催化、光电子、传感等领域中都有重要的应用价值。
这篇综述主要总结了关于CQDs的最近的发展，介绍了CQDs的合成方法、物理化学性质以及在生物医学、光催化、环境检测等领域的应用。
1 引言在过去的20年间，鉴于量子点特殊的性质，尤其是量子点相对于有机染料而言，容易调节的光学性质和抗光降解性质，使量子点得到了广泛的关注。
如果量子点可以克服造价昂贵、合成条件严格和众所周知的高毒性等缺点，则有望广泛地应用于生物传感和上物成像领域。
最近几年，量子点的研究非常活跃，尤其是关于它在生物和医学中的应用。
量子点一般是从铅、镉和硅的混合物中提取出来的，但是这些材料一般有毒，对环境也有危害。
所以科学家们开始在一些良性化合物中提取量子点。
因此，很多的研究均围绕着合成毒性更低的其它材料量子点来进行，这些替代材料的碳量子点，如硅纳米粒子、碳量子点均具有优异的光学性质。
相对金属量子点而言，碳量子点无毒害作用，对环境的危害很小，制备成本低廉。
它的研究代表了发光纳米粒子研究进入了一个新的阶段。
2 碳量子点的合成大多数的碳量子点主要是由无定形的碳到晶化的碳核组成的以sp2杂化为主的碳，碳量子点的晶格间距和石墨碳或者无定形层状碳的结构一致。
如果没有其他修饰试剂的修饰碳量子点表面会含有一些含氧基团，而含氧基团的多少和种类与实验条件相关。
发光碳量子点的合成方法可以分为两大类（图一），化学法和物理法。
图一碳量子点的制备方法2.1化学法2.1.1电化学法Zhou利用离子液体辅助电解高纯石墨棒和高温热解纯定向石墨(HOPG)于离子液体和水溶液中，通过控制离子了液体中水的含量得到不同荧光性质的荧光纳米粒子、纳米带、石墨等产物。
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碳量子点光催化
碳量子点光催化是一种基于碳量子点的光化学反应技术。
碳量子点具有优异的光电性能、催化活性和生物相容性，可以作为一种新型的光催化剂应用于环境保护、能源转化和生物医学等领域。
碳量子点光催化技术主要利用碳量子点的光催化性质，在光的作用下通过光化学反应来实现某些化学反应，例如水的光解、二氧化碳的还原、有机物的降解等。
此外，碳量子点光催化技术还可以用于制备高效的光催化剂，并且具有较低的成本和良好的环境友好性。
目前，碳量子点光催化技术已经在许多领域得到广泛应用，例如环境污染治理、太阳能电池、人工光合成等。
未来，随着碳量子点光催化技术的不断发展和应用，它将在更多领域发挥重要作用，为人类的可持续发展作出贡献。
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