CQD-Based Composites as Visible-Light Active Photocatalysts for Purification of Water

Abstract

The unique physicochemical properties of carbon quantum dot-(CQD)-based photocatalysts, notably their exceptionally good light absorption in the UV and near-visible region, tunable photoluminescence, extraordinary upconversion photoluminescence, outstanding electron affinity, and photoinduced electron transfer, and electron mobility, have attracted considerable attention in different photocatalytic applications. In this review, we summarized the fundamental mechanism and thermodynamics of heterogeneous photocatalysis of aqueous pollutants and the fundamental multifaceted roles of CQDs in photoredox process. Furthermore, we discussed the recent developments in the use of CQD-based materials as visiblelight active photocatalysts in water purification. Finally, the challenges and future direction of CQD-based materials as photocatalytic materials for environmental decontamination were highlighted.

Fabrication of “electroactive cells” using bio-inspired polydopamine-derived carbon nanoparticles for manipulation of cells with electrical stimulation

“…Carbon nanoparticles (CNPs) or carbon nanodots are extremely useful in many applications, including metal ion sensing ( Gao et al, 2016 ; Torres Landa et al, 2022 ), diagnostic probes ( Bhunia et al, 2013 ; Yan et al, 2013 ; Yu et al, 2022 ), nontoxic labeling ( Das et al, 2019 ), drug carriers ( Wang et al, 2013 ), hydrogen generation (Jana et al, 2021; Zhao et al, 2021), specific catalysts ( Makama, Umar and Saidu, 2018 ), and so on. Due to their graphite-like multilayers ( Oza et al, 2016 ), nanoscale sizes, and fluorescence, CNPs may also be useful in biomedical applications to replace other fluorescent dyes.…”

Band edge positions as a key parameter to a systematic design of heterogeneous photocatalyst

“…The ability of any semiconductor to undergo spontaneously photocatalytic reaction on its surface is governed by the relevant redox potential of the acceptor chemical species, which requires to be below (more positive) than the potential of the conduction band electrons, and the donor chemical species that needs to be above (more negative) than the potential of the valence band holes [16,17]. Beside the band edge positions the appropriate band gap energies of general catalytic reaction; water splitting and photodegradation of organic pollutants, are a convenient way to discover photocatalytic semiconductor candidates.…”

Removal of methyl orange (MO) using carbon quantum dots (CQDs) derived from watermelon rinds

“…CQDs which embarked their way as a class of carbonbased nanomaterials over the past decade can be seen have quasi-spherical in shape, discrete and less than 10 nm in size. Obviously, due to their unique characteristics they had attracted huge interest in many fields such as bioimaging, biosensing, electrocatalysis, photocatalysis and nanomedicine [9,10]. CQDs, primarily consist of amorphous carbon together with nanocrystalline regions of sp²-hybridized graphitic carbon.…”