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Apart from garnering the dimension effect, it is the synergistic advantage of constituent elements that contributes to enhanced properties in nanocomposites in comparison to pristine counterparts. While in some cases, nanocomposites have been obtained by introducing nanoparticles/nanofibers as fillers to reinforce host materials, plethora of reports employed in situ synthesis of nanocomposites. Novel quantum effects and enhanced surface-to-volume ratio in nanocomposites are reported to contribute towards extraordinary physico-chemical properties. Characteristics of nanocomposites are well reported to be precisely adjusted by modifying nanoparticles/nanofiber size, shape, dispersion and concentration during synthesis. Some of the prominent materials which are used in the synthesis of nanocomposites are carbon nanotubes, graphene, nanoclays, metal nanoparticles, nanostructured ceramics, etc. Their adaptability makes them suitable for use in a variety of industries, such as the biomedical, automotive, aerospace and electronics sectors. Here, exciting opportunities exist for creating innovative materials with improved performance and multifunctionality. This report provides emphasis on the gas sensing properties of carbon-based nanocomposites.
Department of Basic Sciences and Humanities, Maharashtra Institute of Technology, Aurangabad, India
Kunal Datta
Deen Dayal Upadhayay Kaushal Kendra Dr. Babasaheb Ambedkar Marathwada University Aurangabad (MS), India
*Address all correspondence to: artirushi33@gmail.com
1. Introduction
Pollution is certainly among most ubiquitous and invincible threat to the entire creation. Among the spectrum of pollutions, air pollution is certainly the domain of unfathomable adversities owing to its fundamental contribution for existence, lack of knowledge and absence of adequate purification measures. The constituents of air, when present in a higher than requisite concentration led to severe detrimental effects for both flora and fauna. These materials, sometimes referred to as contaminants, can exist as gases, liquid droplets or solid particles. They can originate from a wide range of natural and man-made sources and have light to long-rooted impacts on the ecosystem, the climate, and human health [1]. Ash, dust, sulphur dioxide and other gases are released during volcanic eruptions, smoke, particle debris, and gases like nitrogen oxides and carbon monoxide that are released during forest fires are some of the natural sources of pollutants [1]. Meanwhile, exhausts from automobiles, industrial emissions, and agricultural activities with high use of pesticides are the anthropogenic sources of pollutant emission. Some prominent air pollutants observed are particulate matter, nitrogen oxides, sulphur oxide, carbon monoxide [2], volatile organic compounds [3], etc., as shown in Figure 1. Prolonged exposure to these pollutants is found to be hazardous to the human body as they create several health problems such as skin issues, lung disorders and pulmonary diseases. Although the effect of pollution on human beings is most studied and reported, the irreparable damage that is being caused to the entire climate and biodiversity is far from being measured to a reliable extent.
Figure 1.
Major air pollutant present in the environment.
The use of green energy sources, regulations by the government on man-made pollution sources, technological solutions, for example, creating greener vehicles and power generation technologies, and awareness and education regarding the negative effects that air pollution has on human health and the environment, could be the necessary steps to curb pollution for coming generations, yet considering current environmental, where human is under eclipse of airborne pollutants, sensitive, selective and detecting technique is required to have real-time monitoring of the air condition [4]. This will assist in implementing proactive safety measures prior to the major hazard. Aplenty of technological interventions have been made, and some of the techniques have gained commercial success.
The following Table 1 shows some of the air pollutant detection techniques along with their working principle [5, 6, 7, 8, 9, 10, 11, 12].
Sr. No.
Methods for detecting air pollution
Working principle
Application
Ref.
1
Continuous Emission Monitoring Systems (CEMS).
These systems track pollutants produced in real time from industrial sources.
Particulate matter (PM), nitrogen oxides (NOx), sulphur dioxide (SO2), and other pollutants are measured by these devices.
These methods, which are frequently combined, are essential for controlling and keeping an eye on air quality. Applications range from industrial pollutants to urban air pollution, enhancing public health and fostering a healthier environment.
The employment of detection techniques is a major factor that governs the performance of any detection approach. Warrant of ultimate reliability in performance of any detection technique combined with practical demands of ultra-low power consumption and low footprint solution, novel materials are under continuous investigation by scientific and technological community alike. A wide variety of materials, namely carbon nanotubes, conducting polymers [13], graphene [14], porphyrins [15], metal oxides [16], etc., have accepted global recognition as potential gas sensing platforms. In order to alleviate individual shortcomings and to obtain synergistic effects, composites of these materials are relied upon in comparison to individual materials. Finally, the use of nanostructured composites has shown significant potential in real-time monitoring at an extremely low footprint, often resulting in a lab-on-chip realm.
Nanocomposites are cutting-edge materials obtained by combining nanoparticles with a bulk matrix material to create a material with special qualities and attributes that set it apart from conventional composites and separate components [17]. The concept of nanocomposites looks forward to harnessing attractive properties of contributing constituents with previously unachieved flexibility and physical property improvements. These materials are prospective for a wide range of industrial applications because of their remarkable mechanical, electrical, thermal and barrier capabilities, which have garnered them much attention in recent years. Natural structures such as the structure of the bone and abalone shell contain nanocomposites. Materials rich in nanoparticles have been used for a long time before their physical and chemical properties have been fully understood. Nanoscale organo-clays have been employed since the middle of the 1950s to regulate the composition of gels or the flow of polymer solutions. Although the word “nanocomposites” was not widely used, textbooks on polymer/clay composites were available by the 1970s [18].
Because of the very high aspect ratio and/or surface-to-volume ratio of the reinforcing phase, nanocomposites differ from other common composite materials. The particles (like minerals), sheets (like exfoliated clay stacks), or fibres (like carbon nanotubes or electrospun fibres) can all be components of the reinforcing material. The area of the interface between the matrix and the reinforcing phase(s) is typically orders of magnitude bigger than in conventional composite materials. There is a noticeable influence on the matrix material’s characteristics near the reinforcement. It should be noted that the degree of thermoset cure, the mobility and conformation of the polymer chain, the degree of ordering of the polymer chain, and the crystallinity of polymer nanocomposites can all vary significantly and frequently. Because of the huge surface area of the reinforcement, a relatively modest amount of nanoscale reinforcement can have a noticeable impact on the composite’s macroscale characteristics. Comparing carbon nanotubes to their bulk counterpart, for example, increases both electrical and thermal conductivity.
Some of the most notable properties of nanocomposites are provided in Figure 2. The discussion of the properties of nanocomposites is provided below:
Mechanical Strength: Nanoparticles can significantly increase mechanical properties [19], including hardness, modulus and tensile strength, even at very low concentrations.
Electrical Conductivity: A composite electrical conductivity can be produced by certain nanoparticles, especially those based on carbon, like graphene or carbon nanotubes [20].
Barrier Properties: Due to their remarkable ability to withstand gases, liquids and even electromagnetic interference, nanocomposites find extensive application in packaging and electrical fields.
Lightweight: Despite their enhanced properties, nanocomposites are often lightweight, which makes them attractive for usage in automotive [21] and aerospace [22] applications.
Optical Properties: Nanoparticles can be employed in sensors and optics by modifying the composite’s optical characteristics, such as transparency, colour or opacity.
Figure 2.
Properties of nanocomposites.
This report sheds light on nanocomposites that use carbon nanoforms as their primary constituent. A vast range of charge transport properties is exhibited by the allotropic forms of carbon (amorphous and polycrystalline graphite, carbon black, fullerenes, nanotubes and graphene), which have sparked basic and applied research for the creation of new devices based on micro- and nano-sized electronic systems. Figure 3 gives a pictorial representation of different carbon allotropes. By fusing the characteristics of each separate phase, carbon-based nanomaterials provide the opportunity to enhance device performances and create unique multifunctional material systems [23].
Figure 3.
Carbon allotropes used in the synthesis of carbon-based nanocomposites.
Materials that can effectively get mixed with carbon-based nanoscale materials, including graphene, nanoparticles or nanotubes, contribute to carbon-based nanocomposites. Depending on the particular material utilised, carbon-based nanocomposites can be achieved by a broad spectrum of techniques, among which covalent and non-covalent functionalization can be considered as classic methods.
In order to achieve covalent functionalization of carbon nanotubes, guest material is chemically attached to the sidewall of nanotubes through the formation of covalent adducts [24]. Although such a method offers stronger binding of the guest material, reactive chemical treatment mostly results in an irreversible hybridization shift from sp2 to sp3 and conjugation loss [25]. Covalent functionalization of carbon nanotube sidewalls includes methods, namely oxidative purification, amidation, esterification, thiolation, hydrogenation and electrochemical functionality, which have been adopted for covalent functionalization [26]. On the other hand, non-covalent functionalization is a supramolecular approach. Through π-π interfaces, aromatic compounds like anthracene, phenanthrene, pentacene, porphyrin, pyrene and CNT or graphene interact with each other. The non-covalent functionalization route is a traditional supramolecular method where the surface tailoring of SWNTs is caused by a variety of adsorption forces, including hydrogen bonds, Van der Waals force, electrostatic force, and π-stacking interactions [26, 27, 28, 29, 30, 31, 32]. The interaction of polymers with the CNT surface via wrapping adds up to better dispersion of CNT in water and organic solvents, apart from retaining the attractive surface properties of CNT sidewalls. Polymers and conducting polymers have been abundantly used for non-covalently functionalizing CNT surfaces by simple dip coating method [33] or electrochemical method [34], the latter offering excellent control over the thickness of the polymeric layer on CNT [35]. Enhanced conductivity of polymer/CNT is well accepted for chemical sensing applications [36, 37, 38]. Composites synthesised by in situ chemical polymerisation [39] are reported to have improved the electrical conductivity, electrochemical capacitance or mechanical strength of the polymer. On the other hand, electrochemical polymerisation has been reported to form a donor-acceptor complex with enhanced electroactivity and conductivity of the composite films [40]. Porphyrins and/or metalloporphyrins are among excellent functional materials by dint of their structural aspects and can be attached to CNT sidewalls in an extremely facile manner [41]. As an excellent example of synergy, while the electrical conductivity of porphyrins/metalloporphyrins is not adequate for electrical transduction [42], these fascinating classes of macrocycles are highly prospective functionalizing entities for highly conducting backbones, most popularly, carbon nanotubes. Non-covalent functionalization with porphyrins/metalloporphyrins maintains the graphitic structure of CNTs [43] in an excellent manner, retaining the surface properties of CNTs [44], and this ensures efficient sensing prospects. Van der Waals forces had an impact on the functionalization of SWNTs during the solution phase, as reported by Nakashima et al. [45] in their initial study on the creation of porphyrin-functionalized CNTs. This specific work has really ushered in a new phase of porphyrin(s)-mediated CNT functionalization. With their highly polarizable aromatic porphyrinic cores and strong interaction with π-conjugated graphenic sidewalls, porphyrins are appealing options for the non-covalent functionalization of carbon nanotubes [45, 46, 47]. For non-covalent functionalization of graphene, several nonsolvents for reduced graphene, namely, benzene, hexane, oxylene, and dichloromethane, have been reported [48]. The carboxylate groups facilitate noncovalent functionalization locations to the protonated amine terminals of end-functional polymers after the chemical reduction of graphene oxide [49]. The additional benefit of functionalizing the CNT side wall, graphene, reduced graphene, GO surface, or creating a composite is that it enhances sensor recovery characteristics because the analyte cannot come into direct contact with the CNT surface in this configuration. In fact, the sluggish desorption of analytes due to the honeycomb structure of CNTs and the high binding energy of gas analytes reflects the poor recovery behaviour in pristine CNT-based sensors. As a result, there is a great deal of interest in research on functionalized or composite architectures of CNTs to address the issues of selectivity and recovery of pristine CNT-based sensors.
Although the spectrum of synthesis techniques for carbon-based nanocomposite is extremely vast, as could be perceived from the above discussions, a generic pedagogy towards achieving the same is provided in Figure 4.
Figure 4.
Procedure of synthesis of carbon-based nanocomposites.
4. Gas sensing applications of carbon-based nanocomposites
4.1 Sensing mechanism
Both CNT and graphene, the most prominent members of carbon nanoforms applied for sensing applications, largely rely on changes in resistive properties on exposure to gaseous analytes/noxious vapours through donor-acceptor interactions [50, 51, 52]. CNTs’ circular curvature causes σ-π rehybridization, which causes three σ bonds to be somewhat out of plane. In order to make up for this, the π-orbital is now asymmetrically distributed both inside and outside the nanotube’s cylindrical wall [53]. Because of the deformed electron clouds, a rich π-electron conjugation arises outside the tube, which greatly increases the electrochemical activity of CNTs. Molecules that give or take electrons from the surface of carbon nanotubes (CNTs) include NO2, NH3, O2 and others. These molecules alter the overall conduction behaviour of the CNTs. In essence, the p-hype behaviour of a growing nanotube is caused by the adsorption of O2. Therefore, well-mechanised effects arise from the donation or withdrawal of electrons to the bulk or surface of nanotubes. The overall sensing phenomena are shaped by enhanced molecule adsorption at room temperature and subsequent charge transfer. Gas molecules can be adsorbed at the surface of a single tube, at due interstitial in tube bundles, in a groove above the space between two adjacent tubes, and inside tubes and nanopores [53]. The detection of NO2 and NH3 by a single SWNT FET was initially reported by Kong et al. [54]. This specific endeavour represented a logical progression of a finding from research by Zhou et al. [55], in which the authors had described the FET characteristics of SWNTs integrated in a back-gated configuration. In just one or 2 minutes, Kong et al. [54] saw three orders of shift in the conductance of SWNTs to even 2 ppm concentration of NO2 and 0.1% concentration of NH3. Someya et al. [56] reported using a similar backbone sensing modality with a response time of 5–15 s to detect saturated gaseous content of methanol, ethanol, 1-propanol, 2-propanol and test-butanol. Novak et al. [57] demonstrated the use of a CHEMFET based on an SWNTs network for the detection of dimethyl methylphosphonate (DMMP). In this instance, a sub-ppm level detection was reported. The study’s most important finding was the sensor’s quick recovery through the use of a positive gate bias. Subsequently, the results of Chang et al. [58] further established this recovery strategy. Valentini et al. [59] created a chemiresistor-based sensor using CNT mats that could detect NO2 as low as 10 ppb. The sensor was examined for a high operating temperature, nevertheless. Li et al. created a simple SWNT-based chemiresistor by drop-casting well-dispersed SWNTs onto premade interdigitated Au electrodes [60]. The sensors were effectively used for NO2 and nitrotoluene ppb level measurement. The sensors did not recover quickly unless they were exposed to UV radiation. Suehiro et al. [61] used dielectrophoresis for the first time to construct an ammonia sensor based on the MWNT network. Using CVD, Li et al. [62] have reported the direct synthesis of silicon nanotubes (SWNTS) on interdigitated Pt and Ti electrodes on a Si/SiO2 substrate. The sensors demonstrated the ability to detect concentrations of NH3 and NO2 as low as 1 and 125 ppb, respectively. Goldoni et al. [63] reported on the impact of contaminants created during the synthesis and purification of SWNTs on the sensing characteristics of SWNTs. A CNT film-based H2 sensor with a detection limit of 10 ppm at room temperature has been fabricated, according to Pierton et al.’s publication [64]. According to Matranga and Bockrath’s theory [65], CO may be detected via hydrogen bonding with the hydroxy groups on the CNT.
In a similar fashion, while investigating the effect of ammonia on graphene nanostructures, Freddi et al. have suggested electron transfer to graphene due to the overlapping of ammonia’s highest occupied molecular orbital (HOMO) and graphene orbitals, with a pivotal role of defects and edges in the graphene [66]. In spite of a plethora of reports on pristine CNTs/graphene-based gas sensors, the stiffest hurdle lies in stiff limitations with transduction mechanisms. At this particular point, carbon-based nanocomposites offer wide versatility and additionally restrict the nanotube/graphene surface from coming into direct contact with the analyte, a problem that is well reported to deteriorate the recovery characteristic of sensors.
4.2 Gas-sensing applications
Among earlier studies, Zhang et al. reported electrochemical functionalization of SWNTS with poly (aniline), where the chemiresistive sensor backbone detected ammonia down to 50 ppb concentration [67]. An ultrathin CPPy layer-wrapped carbon nanotube (CNT) hybrid has been obtained through vapour deposition polymerisation by Park et al. [68], which was further decorated with monodispersed Pd nanoparticles on the PPy-CNT hybrid surface that resulted in high-performance field-effect transistor to trace hydrogen at a level of 1 ppm at room temperature. By adding ammonium persulfate to an aniline solution containing carbon nanotubes (CNTs), polyaniline (PANI) nanoparticle-coated CNTs and PANI nanofiber can be created [69]. The resulting PANI thin film exhibits highly sensitive NH3 sensing down to 200 ppb with excellent response/recovery time. It works in the room temperature environment. In order to non-covalently functionalize SWCNTs with poly(N-methyl pyrrole) (P[NMP]) by π−π interaction, Datta et al. [35] used an electrochemical method. The resultant product had a good linear response for ammonia sensing, ranging from 10 ppb to 1 ppm. This study focuses on how the thickness of the polymeric layer in the aligned SWNTs matrix affects the behaviour of the sensors. Using HCl as a dopant and ammonium persulphate (APS) as an oxidant for the detection of NH3, an in situ chemical oxidative polymerisation approach was used to create the nanocomposite of PPy and carboxylated multiwalled carbon nanotubes (MWCNT–COOH). This study focused on how the content of MWNTs affects the sensitivity of the composite backbone [70]. Zhang et al. [71] have documented a change in polyaniline’s sensing behaviour from p-type to n-type by an examination of the interface effect. At the core–shell interface of hierarchical PANI/CNT composites, n-type PANI and p-type CNTs form p–n hetero junctions. The detection limits for NO2 and NH3 by p-type PANI/CNT and n-type PANI/CNT are as low as 16.7 and 6.4 ppb, respectively. In order to monitor health, Hong et al. [72] presented a stretchy array of multifunction sensors that resemble skin and are based on polyurethane foam coated with MWCNT-PANI composite. The sensors can detect skin temperature, wrist pulse and ammonia gas simultaneously. Wu et al. employed tetra-b-carboxyphthalocyanine cobalt(II) to fabricate PANI/multiwalled CNT (MWCNT) nanocomposites for rapid detection of ammonia [73] with a response/recovery time of 5.0/12.0 s to 100 ppm NH3. S. Kumar et al. have functionalized SWNTs with polyethylenimine with significant repetitive behaviour with the assistance of UV irradiance [74]. The investigators achieved 37% higher sensitivity with functionalized structure compared to pristine SWNTs-based sensors.
Among prominent reports of macrocyclic compounds functionalized CNT sensors, Ndiaye et al. employed a simple dispersion technique to non-covalently functionalize SWNTs with pthalocyanines and porphyrin derivatives [75]. Detection of BTX-type gases, especially toluene, was investigated in chemiresistive and Quartz crystal microbalance-based mass sensing modes. Contrary to the generic perception of analyte binding with CNTs, the authors reported slower desorption of analytes functionalized backbone in comparison to pristine SWNTs matrix. The QCM-based sensor could detect target vapour sensitively within a detection window of 60–1200 ppm. Through the interaction of glycyl-substituted porphyrin with non-modified CNTs and PPy/SWCNT-COOH film, Lvova et al. synthesised SWCNT–porphyrin composites [76]. Using the CNT-Porphyrin composite as a QMB coating allowed for the detection of 1-butanol at 46 ppb levels. Shirsat et al. used porphyrins with a variety of functional groups and core metal ions to functionalize aligned SWNTs backbone in an all-encompassing strategy to comprehend the selectivity behaviour of porphyrin/metalloporphyrin functionalized CNT sensor devices [77]. A pattern recognition analysis was employed to analyse the specific behaviour of individuals sensing backbones to saturated vapours of MEK, acetone, methanol and ethanol. This particular study constituted an important step towards specific sensing of volatile organic compounds (VOCs) and the development of e-nose platforms. An electrochemical functionalization route was adopted by Sarkar et al. to functionalize SWNTs with poly(tetraphenyl porphyrin) [78]. The authors applied different charge densities to control functionalization layer and correlated sensing performance with the thickness of poly(tetraphenyl porphyrin) layer. The lowest detection limit of the optimised sensor was recorded to be 9 ppm for oxygen vapour. The sensing was carried out in a field-effect transistor structure, and the electrostatic gating effect was found to be the primary sensor mechanism. This report stressed the stable behaviour of the sensor device for a period of 180 days. A chemiresistive platform that employed iron tetraphenyl porphyrin and tetraphenyl porphyrin for non-covalent functionalization of aligned SWCNTs has been reported by the authors [41]. The functionalization was carried out by the facile solution casting method [41]. The hybrid sensor could detect benzene at a presence of 1 ppm concentration. The better sensing response of iron tetraphenyl porphyrin functionalized SWCNTs sensor was attributed to the vacant d-orbital of the central Fe atom that acted as a point of electron reception. Taking this investigation further, the authors, at a later course, investigated the effect of iron and cobalt as central metal ions in tetraphenyl porphyrin towards functionalization of SWCNTs on selective behaviour of the chemiresistor platform towards benzene, toluene and xylene [79]. A detailed insight into the mechanism was presented in the report, and selective behaviour could be observed with toluene at a lower detection limit of 500 ppb. A chemiresistive sensor array was reported by Liu et al. through non-covalent functionalization of single-walled carbon nanotubes (SWCNTs) with late first-row transition metal complexes of meso-tetraphenyl porphyrin [80]. Vapours of a variety of volatile organic compounds (VOCs) were introduced into the sensor array. A statistical analysis of the results revealed that typical VOCs could be successfully classified into five categories—aliphatic hydrocarbons, alcohols, ketones, aromatic hydrocarbons and amines—with an accuracy rate of 98%.
The different gas-sensing behaviours of virgin graphene, graphene (GO), and reduced graphene (rGO) are caused by their unique structural characteristics. Due to its two-dimensional structure, graphene is extremely sensitive to the adsorption of gas molecules in terms of electron transport [81]. Compared to pristine graphene, reduced graphene oxide (rGO) is more active as a sensor element due to inherent structural defects and residual oxygen groups [82]. Tang et al. [82] have reported a scalable technique to obtain an ultrathin layer of poly(pyrrole) through electro-polymerisation on rGO as support material to obtain room temperature sensors for ammonia. Biswas et al. [83] have developed a Schottky diode electrode based on multi-polymeric layer (PTFE, PVDF and PANI) on top of BiVO4 to obtain a heterojunction where GO has been employed as a filler. On exposure to 1800 ppm of ammonia, the sensor exhibited a sensitivity value of 3654, which was two times higher than the pristine (PTFE, PVDF and PANI), an improvement attributed to the increase in conductivity with added GO (0.04 wt%) nanosheets into polymeric layer. The Nanocomposite of polypyrrole (PPy) and graphene nanoplatelets (GN) was synthesised by a sol–gel process combined with in situ chemical polymerisation and finally decorated with titanium dioxide for the detection of ammonia [84]. The sensors could detect NH3 molecules at room temperature with reproducibility and excellent selectivity. A nanocomposite of graphene-poly(pyrrole)-tungsten oxide [85] could be achieved by oxidative polymerisation of pyrrole in the presence of GO. The nanocomposite could detect ammonia in the 5–15 ppm range at a sensitivity factor of 58% with 50s/120s response and recovery time at an average. Most importantly, the sensor behaviour was unperturbed at 50% relative humidity. Poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene] has been employed by Sahu et al. towards the formation of a nanohybrid with GO to fabricate a polymeric thin film transistor [86], that showed a positive shift in threshold voltage ranging from −1 V to +23 V after exposure to 30 ppm concentration of NO2. According to the authors, the adsorption of NO2 molecules in the hybrid PBTTT/GO film causes the hole carrier concentration in the composite film to rise, which in turn causes an increase in drain current. Paramar et al. reported sensing of toluene with graphene/PANI nanocomposite films obtained in the solution phase [87]. The sensors exhibited room temperature detection of 100 ppm toluene with good response recovery behaviour. The authors suggested that the presence of active sites on the graphene in C-PANI and swelling junctions between graphene flakes is responsible for sensing behaviour. Husain et al. reported enhanced electrical conductivity in polythiophene/graphene nanocomposites due to an extended π-conjugated system. The sensor exhibited detection of ethanol with a low detection limit of 400 ppm and complete reversibility within 360 s at room temperature [88].
Although carbon-based nanocomposites have demonstrated potential for sensing a diverse range of gaseous analytes, a few issues remained as a critical constraint towards commercial success
Achieving a homogeneous dispersion of carbon-based nanomaterials throughout the sensor matrix without clustering or aggregation.
Scalable manufacturing process to achieve large-scale production through laboratory synthesis.
Consideration of response and recovery behaviour of sensors as physisorption of gas analyte on sensor surface leads to slow recovery.
Dedicated investigation is needed to achieve a reliant lifetime of sensors under challenging situations, such as humid conditions.
Further study on cross-sensitivity behaviour of nanocomposite sensors to achieve selective behaviour.
Cost-effectiveness for commercial viability.
To sum up, carbon nanocomposites are an exciting and quickly expanding area of materials science that presents a plethora of opportunities for research and development. Because of their special combination of qualities, they can be adapted to address real-life challenges, from enhancing medical treatments to increasing the effectiveness of transportation. The future technologies are anticipated to be significantly shaped by nanocomposites as research and production techniques advance. Continued research and developments in this field are essential for reliable, cost-effective, low-footprint solutions that can be easily interfaced with standard industrial/commodity protocols.
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Written By
Arti Rushi and Kunal Datta
Submitted: 30 April 2024Reviewed: 08 July 2024Published: 28 August 2024
Open access peer-reviewed chapter
