Recent progress on performances and mechanisms of carbon dots for gas sensing

Abstract

Carbon dots (CDs), as an attractive zero‐dimensional carbon nanomaterial with unique photoluminescent merits, have recently exhibited significant application potential in gas sensing as a result of their excellent optical/electronic characteristics, high chemical/thermal stability, and tunable surface states. CDs exhibit strong light absorption in the ultraviolet range and tunable photoluminescence characteristics in the visible range, which makes CDs an effective tool for optical sensing applications. Optical gas sensor based on CDs have been investigated, which generally responds to the target gas by corresponding changes in optical absorption or fluorescence. Moreover, electrical gas sensor and quartz crystal microbalance sensor whose sensing layer involves CDs have also been designed. Electrical gas sensor exhibits an increase or a decrease in electrical current, capacitance, or conductance once exposed to the target gas. Quartz crystal microbalance sensor responds to the target gas with a frequency shift. CDs greatly promote the absorption of the target gas and improve the sensitivity of both sensors. In this review, we aim to summarize different types of gas sensors involving CDs, and sensing performances of these sensors for monitoring diverse gases or vapors, as well as the mechanisms of CDs in different types of sensors. Moreover, this review provides the prospect of the potential development of CDs based gas sensors.

The Asphaltenes: State-of-the-Art Applications and Future Perspectives in Materials Science

“…Carbon dots are small carbon-based nanoparticles with sizes typically ranging from a few nanometers to several micrometers in diameter. They are synthesized using bottom-up methods such as solvothermal, hydrothermal, and microwave-assisted synthesis from carbon precursors such as citric acid or glucose. , Many successful attempts have been made to employ these carbon-based materials in gas-sensing devices for detecting various gases, including hydrogen, ammonia, carbon monoxide, carbon dioxide, nitrogen oxides, methane, oxygen, and volatile organic compounds (VOCs). Furthermore, researchers have explored various ways to functionalize and integrate these materials with metal oxides, metals, and conducting polymers, striving to amalgamate the exceptional attributes of carbon-based materials, including their elevated surface area and chemical resilience, with the sensitivity and selectivity of traditional gas sensing materials to create hybrid sensors with improved performance despite the advantages that carbon-based materials offer, and the extensive research conducted to investigate their utility in gas-sensing applications, significant limitations still need to be addressed, including the high cost and complexity of synthesizing these materials, which could impede their widespread production and practical applications.…”

Smart and intelligent optical materials for sensing applications

“…The SI also published three dedicated reviews on carbon quantum dots (CQDs) and sustainably derived CQDs for sensing, imaging, and biological applications by Rawat et al [15], Atulbhai et al [16], and Sun et al [17], along with the available synthesis methods. These articles highlighted CQD biological, chemical, and physical characteristics, and briefly discussed light‐emissive nanomaterials such as CQDs, quantum dots (QDs), rare earth‐doped nanocomposites, and metal nanoclusters (NCs).…”

Synthetic Nanoarchitectonics of Functional Organic–Inorganic 2D Germanane Heterostructures via Click Chemistry

“…Beyond the intrinsic water solubility and fluorescence properties offered by CDs, this carbon-based 0D material is also known for its excellent capability for optically monitoring several biotargets, including explosive nitrocompounds, metal ions, proteins, [51,52] as well as some (in-)organic volatile compounds. [53] Further, the inherent sp 2 -hybridized carbon atoms of CDs also provide a prominent core for supramolecularly interacting with small hydrophobic carbon nanoparticles via π-stacking interactions. [54] In particular, this last feature has been considered here to exploit the 0D/2D heterostructure as an unconventional optical sensing system for the determination of carbon nanoparticles in water using FRET phenomenon (Figure 4).…”