Repurposing the domestic organic waste into green emissive carbon dots and carbonized adsorbent: A sustainable zero waste process for metal sensing and dye sequestration

Carbon dots derived from natural sources and their biological and environmental impacts

“…8e). 116 The domestic organic waste-derived CDs emitted green fluorescence and were highly sensitive to Cr 6+ (Fig. 8f and g), which effectively decreased the detection limit of Cr 6+ to the picomolar range (81 pM, Fig.…”

“…Furthermore, Tan et al successfully prepared fluorescent CDs using natural products as carbon sources and found the great antibacterial activity of the products against Pseudomonas fragi. 121 Taking advantage of the doped 116 Copyright 2021, Elsevier. (j) CDs prepared from ginkgo for sensing SASP.…”

Heavy metal ion detection using green precursor derived carbon dots

“…The natural presence of heteroatoms in biomass derived precursors saves the additional steps related to the incorporation of external heteroatoms ( Meng et al., 2019 , p. 20). The abundance of functional groups in biomass structure provides multiple pathway reactions ( Liu et al., 2020b ; Das et al., 2021 ). If it comes from agricultural by-products, it generally contains an average composition of 40–50% cellulose, 20–30% hemicellulose, 20–25% lignin, and 1–5% ash ( Kang et al., 2020 ; Mahat and Shamsudin, 2020 ).…”

“…Although the synthesis of CDs from renewable bio-sources has its own challenges, it has been a desirable approach ( De and Karak, 2013 ), because of several advantages, like sustainability, low cost, added value to waste, pollution-free materials, and green preparation methods ( Liu et al., 2019c ; Liu et al., 2019b ; Singh et al., 2019 ; Yu et al., 2019 ; Ahmadi et al., 2020 ; Boruah et al., 2020 ; Wang et al., 2020a ; Liu et al., 2020a ; Lu et al., 2020 ; Das et al., 2021 ; Ding et al., 2021 ; Lou et al., 2021 ). Moreover, biomass-derived nanomaterials exhibit excellent water solubility, nontoxicity, and good biocompatibility ( Wang et al., 2020b ; Luo et al., 2021 ; Krishnaiah et al., 2022 ).…”

“…retusus) fruit extract ( Atchudan et al., 2017 ) (plant source) Hydrothermal 70 0–2 9 Al (III), Ca (II), Cd (II), Co (II), Cr (III), Cu (II), Fe (II), Fe (III) , Hg (II), Ni (II), Pb (II), and Zn (II) Kiwi fruit peels + ammonium hydroxide ( Atchudan et al., 2021 ) (plant source) Hydrothermal 0.95 and 0.85 5–25 14 19 Al (III), Ca (II), Cd (II), Co (III), Cr (III), Cu (II), Fe (III) , Hg (II), Mn (II), Ni (II), Pb (II), and Zn (III) Betel leaves + aq. ammonia ( Atchudan et al., 2019 ) (plant source) Hydrothermal 0.135 0.3–3.3 4.21 K (I), Cu (I), Na (I), Pb (II), Cu (II), Cr (VI), Zn (II), Fe (II), Cd (II), Ag (I), Fe (III) , Hg (III), and Mn (III) Curauá (Ananas erectifolius) fibers ( Raja et al., 2021 ) (plant source) Hydrothermal 0–30 0.77 – Fe (III) , Na(I), K (I),Mg (II), Ca (II), Ba (II), Cr (II), Mn (II), Fe (II), Co (II), Ni (II), Cu (II), Ag (I), Zn (II), Cd (II), Hg (II), and Al (III) Ripe banana peels + ethylene diamine + L-cysteine ( Das et al., 2021 ) (plant source) Hydrothermal 10–200 ×10 −6 121 × 10 −6 27 Fe (III) , Hg (II), Cu (II), Cr (VI), Cd (II), Mg (II), Na (I), and K (I) Biomass waste (orange peel , ginkgo biloba leaves , paulownia leaves, and magnolia flower) ( Wang et al., 2020a ) (mixture of 4 different plant sources) Hydrothermal 0.088 (MF-CQDs) 0.2–100 8.13 Ag (I), K (I), Na (I), Pb (II), Fe (III) , Fe (II), Zn (II), Cu (II), Mg (II), Ca (II), Al (III), Cd (II), Cr (III), Ba (II), and Hg (II) 0.073 (OP-CQDs) 4.29 0.080 (GB-CQD) 7.72 0.10 (PL-CQDs) 4.74 …”