Volatile organic compounds (VOCs) have attracted world-wide attention regarding their serious hazards on ecological environment and human health. Industrial processes such as fossil fuel combustion, petrochemicals, painting, coatings, pesticides, plastics, contributed to the large proportion of anthropogenic VOCs emission. Destructive methods (catalysis oxidation and biofiltration) and recovery methods (absorption, adsorption, condensation and membrane separation) have been developed for VOCs removal.Adsorption is established as one of the most promising strategies for VOCs abatement thanks to its characteristics of cost-effectiveness, simplicity and low energy consumption. The prominent progress in VOCs adsorption by different kinds of porous materials (such as carbon-based materials, oxygen-contained materials, organic polymers and composites is carefully summarized in this work, concerning the mechanism of adsorbate-adsorbent interactions, modification methods for the mentioned porous materials, and enhancement of VOCs adsorption capacity. This overview is to provide a comprehensive understanding of VOCs adsorption mechanisms and up-to-date progress of modification technologies for different porous materials.

3D-MoS 2 can adsorb organic molecules and provide multidimensional electron transport pathways, implying ap otential application for environment remediation. Here,w e study the degradation of aromatic organics in advanced oxidation processes (AOPs) by a3 D-MoS 2 sponge loaded with MoS 2 nanospheres and graphene oxide (GO). Exposed Mo 4+ active sites on 3D-MoS 2 can significantly improve the concentration and stability of Fe 2+ in AOPs and keep the Fe 3+ / Fe 2+ in as table dynamic cycle,t hus effectively promoting the activation of H 2 O 2 /peroxymonosulfate (PMS). The degradation rate of organic pollutants in the 3D-MoS 2 system is about 50 times higher than without cocatalyst. After a1 40 Lp ilotscale experiment, it still maintains high efficiency and stable AOPs activity.A fter 16 days of continuous reaction, the 3D-MoS 2 achieves ad egradation rate of 120 mg L À1 antibiotic wastewater up to 97.87 %. The operating cost of treating aton of wastewater is only US$ 0.33, suggesting huge industrial applications.

Lignin converted to carbon quantum dots (CQDs) attracts tremendous attention for large-scale production of carbon nanomaterials and value-added disposal of biomass wastes (such as the black liquor from pulping industry and the residue from hydrolysis of biomass). The green synthesis of lignin-derived CQDs is reported via a facile two-step method with the adjustment of acid additives containing N or S. The resulting series of CQDs exhibit bright fluorescence in gradient colors from blue to yellowish green, among which the N, S co-doped CQDs with the addition of 2,4-diaminobenzene sulfonic acid show an optimal fluorescence quantum yield (QY) of 30.5%. The red-shift photoluminescence emission behaviors of these CQDs can be attributed to the increased graphitization degree and reduced optical energy band gaps (2.47 → 2.17 eV) with regard to the incorporation of various heteroatoms. The improved fluorescence QYs are consistent with the variation trend of the increased N/C content in the CQDs. The yellowish green-emissive CQDs with bright fluorescence, strong water solubility, and excellent chemical stability perform well in anti-counterfeiting printing. The promising and sustainable approach for the synthesis of tunable fluorescent CQDs exhibits the value-added utilization of lignin for the fluorescence ink production.

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Carbon quantum dots (CQDs), as a novel fluorescent carbon nanomaterial, have raised worldwide concern on account of their remarkable biocompatibility, water solubility, chemical stability, nontoxicity, high conductivity, and turntable photoluminescence properties. Research on CQDs has been implemented for a dozen years, involving numerous precursors, synthesis methods, properties, and applications. Among them, the conversion of biomass waste into value-added CQDs has been considered as a green synthesis route for CQDs fabrication owing to its low cost, sustainability, environmental friendliness, and commercialization. This review focuses on the promising biomass-derived CQDs, including their advanced synthesis strategy, formation mechanism, modification technology, and application. The innovative up–down joint technique shows great potential in large-scale production of biomass-derived CQDs. The modification technology (size and shape control, heteroatom doping, surface passivation, composites) enables the tuning of their properties for high-quality products. It hopes to provide a comprehensive understanding of biomass-derived CQDs and guidance for future CQDs research directions.

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Pyrolysis experiments between 25 and 800 °C for three main components (cellulose, hemicellulose, and lignin) mixed in different proportions were conducted on a thermogravimetric analyzer (TGA) and pyrolysis−gas chromatography/mass spectrometer (Py-GC/MS). The interactions between the three main components during the pyrolysis of biomass were explored from two aspects, namely thermogravimetric properties and pyrolysis products. The results indicate that interactions existed among the three biomass components in the co-pyrolysis process. The presence of lignin significantly reduces the pyrolysis rate of cellulose and inhibits the formation of sugars (mainly levoglucosan) in the pyrolysis of cellulose and hemicellulose. However, the existence of cellulose or hemicellulose greatly promotes the pyrolysis of lignin to produce phenolic compounds. This finding is meaningful for the application of biomass pyrolysis.

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