Fuel waste to fluorescent carbon dots and its multifarious applications
Graphical abstract
Introduction
The majority of energy needs of humans is met by burning fossil fuels, which leads two major threats to the environment such as green house effect and ozone layer depletion causing global warming, acid rain, etc [1,2]. Regulatory authorities in most countries are seriously concerned with the emission of soot to the atmosphere by various activities. Inhalation of such soot causes many adverse health effects such as lung inflammation, cardiovascular problems and defects in brain activity, etc [3,4]. Therefore conversion of waste soot into value added product is one of the recent scenario among the research community. In other area of contemporary research is the design and synthesis of nanomaterials for diverse fields. Nanomaterials [5] are of great interest owing to their distinctive optical and other functional characteristics which direct them for potential applications in electronic as well as biological fields [6,7]. Among the numerous types of nanomaterials reported, carbon dots (CDs) are emerged as potential competitor to other conventional semiconducting nanomaterials [8]. CDs are characteristically nanomaterials consist of ill-defined nanocrystalline cores with sp2 hybridised carbon sheets (graphite/graphene/graphene oxide) merged by three dimensional sp3 carbon insertions [9]. They were revealed by Xu et al. in 2004 while purifying carbon nanotubes [10]. Generally both top-down [[10], [11], [12]] and bottom-up [[13], [14], [15], [16]] methodologies were known to produce CDs. Notably, a green synthetic approach, under bottom-up method, was introduced by Li et al. in which ethanol was electrochemically treated in NaOH medium for the synthesis of CDs [17]. Thereafter, numerous reports for the usage of inexpensive precursors for the production of CDs followed by various protocols were developed [[18], [19], [20], [21], [22], [23], [24]]. In this juncture, we have also derived the CDs from green resources such as tamarind and centella asiatica via one pot hydrothermal method [25,26]. However, few drawbacks like diversity in particle size, costly processing, small scale production and poor chemical stability were faced while using green resources as precursor [[27], [28], [29]].
Conversion of waste biomass or pollutant into CDs is a contemporary in research which has been kicked off by Lee and his research group [30]. They have introduced bulk synthesis of CDs from food waste via ultrasonication method. Similarly, a few reports were presented for the conversion of soot collected by burning candle, natural gas etc into CDs for biological applications [31,32]. Based on this context, our ultimate aim is to convert a waste material such as kerosene fuel soot into value added product like nanostructured CDs for the effective utilization in the field of photovoltaic as well as sensing fields.
The usage of carbon based materials in photovoltaic and sensing applications are growing interest [[33], [34], [35], [36], [37]]. For instance, in dye-sensitized solar cells (DSCs) integration of graphene sheets into TiO2 photoanodes gave five times higher power conversion efficiencies than those obtained from TiO2 photoanodes without graphene sheets [36]. Imahori et al. reported the efficient hierarchical electron transfer cascade system on a semiconducting electrode by using rGO sheet to anchoring porphyrins/ZnO hybrid materials and that cascade system exhibited remarkably high photocurrent generation with an incident-photon-to-current efficiency (IPCE) of up to 70% compared with the reference device without rGO sheets [30]. Kamat et al. reported the CdSe–graphene composites in quantum dot sensitized solar cells display improved photocurrent response (∼150%) over those prepared without GO [37]. Therefore, it is significant to study the interactions between light harvesting materials and carbon nanomaterials. For interaction studies, porphyrin was selected due to its higher efficiency in dye sensitized solar cells over than other dyes [[38], [39], [40]]. The selected porphyrins were meso-tetrakis (1-methyl-4-pyridinio) porphyrin [TMPyP] and meso-tetrakis(4-sulfonatophenyl) porphyrin [TSPP] shown in Scheme S1.
On the other hand, CDs were highly utilized due to their fluorescence property and water soluble in nature. For instance, Wu et al. developed simple amine-capped C-dots for the selective detection of picric acid (PA) in water medium and explored that there is a strong electrostatic interaction between the amine capped CDs and PA [41]. Liu and co workers were reported, the high fluorescence quantum yield of CDs capped with BPEI using bamboo leaves as carbon source. The prepared CDs were utilized for the sensitive and selective detection of Cu2+ in real water sample [42]. For the sensitivity of Fe3+, the blue emitting CDs were developed from citric acid and ethylene diamine via a hydrothermal method. The mechanism of sensing was due to complex formation between Fe3+ ion and phenolic hydroxyl groups (−OH) on the CDs surface leads electron transfer from excited state CDs to unfilled d orbital of Fe3+ ion [43]. These milieu are tempted us to utilize the KCDs in PET and sensing studies.
In the present work, we have successfully converted the waste soot collected from the kerosene fuel burning into value added product namely carbon dots (KCDs). Since it is reported that CDs have wide range of applications, herein we have utilized the prepared KCDs in multi-target applications such as PET studies with porphyrins in view of usage of KCDs as electron shuttling mediator in cascade system of photovoltaic device and the fluorescent nature of KCDs is effectively used for the selective and sensitive detection of explosives and heavy metal ions. The sensing studies have also been tested in real water sample in order to prove the practical applicability of the analysis. On the other hand, the unreacted soot has also been applied as an affordable filter bed for waste water purification. Therefore, the present manuscript unambiguously gives the knowledge of effective usage of the prepared nanomaterial (Waste to Nano) for multifarious applications.
Section snippets
Materials
Kerosene was purchased from a local provisional store. Porphyrins, [meso-tetrakis (1-methyl-4-pyridinio) porphyrin and meso-tetrakis (4-sulfonatophenyl) porphyrin] were procured from Sigma–Aldrich. Analytical grade sodium carbonate and nitric acid were acquired from LOBA Chemicals (India). Picric acid and other nitro aromatic compounds were purchased from Merck. ZnCl2, NiCl2.6H2O, CuCl2.2H2O, MgCl2.6H2O, CoCl2.6H2O, BaCl2.2H2O, PbCl2, FeCl2, NaCl, KCl, MnCl2.4H2O and FeCl3 were purchased from
Results and discussion
The ultimate aim of this work is the effective utilization of carbon dots from a waste material for multifarious applications in view of sustainable development. From the oxidative acid treatment of kerosene soot, the obtained brown solid product (Scheme 1) was highly water soluble in nature and refrigerated at 4 °C which exhibited the storage stability of more than three months without precipitation. Fig. 1a shows the TEM image of KCDs measured in 20 nm scale which indicates that most of the
Conclusion
In conclusion, the kerosene fuel soot was successfully converted into nanostructured carbon dots via a one-step oxidative acid treatment. The KCDs particles were quasi-spherical in shape and average diameter of 5 nm which consist of various oxygen enclosed surface functionalities imparting excitation independent fluorescence behavior. The intermolecular interactions between the porphyrin and KCDs in aqueous medium were investigated and the possibility of electron injection from porphyrin to
Acknowledgments
V.S. thanks to the Department of Chemistry and BSACIST for the Junior Research Fellowship. M.A.J. thanks the Department of Science and Technology (DST), New Delhi, India for the DST-SERB Project (Ref. No. SB/FT/CS-125/2013, Dt. 30/06/2014). MAJ also thanks to SAIF, IIT Madras for assistance with NMR, HR-SEM and TCSPC facilities. MAJ also acknowledge to Ms. S. Thulasi, project fellow and Ms. G. Loganayagi, PG student for their assistance in soot collections and benchmark experiments. A.K. thanks
References (82)
- et al.
Carbon dots derived from rose flowers for tetracycline sensing
Talanta
(2015) - et al.
Hydrothermal synthesis of highly fluorescent carbon nanoparticles from sodium citrate and their use for the detection of mercury ions
Carbon
(2013) - et al.
Facile synthesis of fluorescent carbon dots using watermelon peel as a carbon source
Mater. Lett.
(2012) - et al.
One-pot green synthesis of carbon dots by using Saccharum officinarum juice for fluorescent imaging of bacteria (Escherichia coli) and yeast (Saccharomyces cerevisiae) cells
Mater. Sci. Eng. C
(2014) - et al.
One-step green synthesized fluorescent carbon nanodots from bamboo leaves for copper a(II) ion detection
Sens. Actuators B
(2014) - et al.
Highly emissive triphenylamine based fluorophores for detection of picric acid
Tetrahed. Lett.
(2014) - et al.
Synthesis of highly luminescent water stable ZnO quantum dots as photoluminescent sensor for picric acid
J. Luminesc.
(2014) - et al.
Removal, preconcentration and spectrophotometric etermination of picric acid in water samples using modified magnetic iron oxide nanoparticles as an efficient adsorbent
Mat. Sci. Eng. C
(2012) - et al.
Selective detection of picric acid using functionalized reduced graphene oxide sensor device
Sens. Actuators B
(2014) - et al.
Highly sensitive and selective sensor based on silica-coated CdSe/ZnS nanoparticles for Cu2+ ion detection
Sens. Actuators B
(2012)
Green and cost-effective fluorescent carbon nanoparticles for the selective and sensitive detection of iron (III) ions in aqueous solution: mechanistic insights and cell line imaging studies
Sens. Actuators B: Chem.
Peat as a natural solid-phase for copper preconcentration and determination in a ulticommuted flow system coupled to flame atomic absorption spectrometry
Anal. Chim. Acta
Ultrasensitive colorimetric detection of Cu2+ ion based on catalytic oxidation of L-cystein
Biosens. Bioelectron.
Mesoporous aluminosilica sensors for the visual removal and detection of Pd(II) and Cu(II) ions
Microporous Mesoporous Mater.
Determination of iron in seawater by high-resolution isotope dilution inductively coupled plasma mass spectrometry after Mg(OH)2 coprecipitation
Anal. Chim. Acta
Chemically tailoring graphene oxides into fluorescent nanosheets for Fe3+ ion detection
Carbon
Optical mesosensor for capturing of Fe(III) and Hg(II) ions from water and physiological fluids
Sens. Actuators B: Chem.
The selectivity of the carboxylate groups terminated carbon dots switched by buffer solutions for the detection of multi-metal ions
Sens. Actuators B
A fluorescent turn-off/on method based on carbon dots as fluorescent probes for the sensitive determination of Pb2+ and pyrophosphate in an aqueous solution
Sens. Actuators B: Chem
Chemistry and microphysics of polar stratospheric clouds and cirrus clouds
Annu. Rev. Phys. Chem.
Can soot particles emitted by airplane exhaust contribute to the formation of aviation contrails and cirrus clouds?
Geophys. Res. Lett.
Langendorff heart: a model system to study cardiovascular effects of engineered nanoparticles
ACS Nano
Emission aktivierter Rußpartikel: die Kehrseite der Medaille moderner Dieselmotoren
Angew. Chem.
Textbook of Nanoscience and Nanotechnology
Introduction in Nonmaterial and Nanotechnology
Nanoparticles types, classification, characterization, fabrication methods and drug delivery applications
Natural Polymer Drug Delivery Systems
Carbon quantum dots and their applications
Chem. Soc. Rev.
Luminescent carbon nanodots: emergent nanolights
Angew. Chem. Int. Ed.
Electrophoretic analysis and purification of fluorescent single-walled carbon nanotube fragments
J. Am. Chem. Soc.
Quantum-sized carbon dots for bright and colorful photoluminescence
J. Am. Chem. Soc.
Electrochemiluminescence of water-soluble carbon nanocrystals released electrochemically from graphite
J. Am. Chem. Soc.
Surface functionalized carbogenic quantum dots
Small
Microwave synthesis of fluorescent carbon nanoparticles with electrochemiluminescence properties
Chem. Commun.
Luminescent carbon dots in a new magnesium aluminophosphate zeolite
Chem. Commun.
Fluorescent carbon nanoparticles: electrochemical synthesis and their pH sensitive photoluminescence properties
New J. Chem.
Fluorescent carbon nanoparticles: synthesis, characterization, and bioimaging application
J. Phys. Chem. C
Simple one-step synthesis of highly luminescent carbon dots from orange juice: application as excellent bio-imaging agents
Chem. Commun.
One-pot green synthesis of nitrogen-doped carbon nanoparticles as fluorescent probes for mercury ions
RSC Adv.
One-step synthesis of amino-functionalized fluorescent carbon nanoparticles by hydrothermal carbonization of chitosan
Chem. Commun.
A novel fluorescent carbon dots derived from tamarind
Chem. Phys. Lett.
Photoinduced interaction of arylamine dye with carbon quantum dots ensued from Centella asiatica
J. Lumin.
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