1. College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China 2. School of Chemistry and Physics and QUT Centre for Materials Science, Queensland University of Technology, QLD 4000, Australia 3. School of Chemical and Biomolecular Engineering, The University of Sydney, NSW 2006, Australia 4. Centre for Future Materials, University of Southern Queensland, QLD 4350, Australia
Surface functionalization or modification to introduce more oxygen-containing functional groups to biochar is an effective strategy for tuning the physicochemical properties and promoting follow-up applications. In this study, non-thermal plasma was applied for biochar surface carving before being used in contaminant removal and energy storage applications. The results showed that even a low dose of plasma exposure could introduce a high number density of oxygen-functional groups and enhance the hydrophilicity and metal affinity of the pristine biochar. The plasma-treated biochar enabled a faster metal-adsorption rate and a 40% higher maximum adsorption capacity of heavy metal ion Pb2+. Moreover, to add more functionality to biochar surface, biochar with and without plasma pre-treatment was activated by KOH at a temperature of 800 °C. Using the same amount of KOH, the plasma treatment resulted in an activated carbon product with the larger BET surface area and pore volume. The performance of the treated activated carbon as a supercapacitor electrode was also substantially improved by>30%. This study may provide guidelines for enhancing the surface functionality and application performances of biochar using non-thermal-based techniques.
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A K Mohanty, S Vivekanandhan, J M Pin, M Misra. Composites from renewable and sustainable resources: challenges and innovations. Science, 2018, 362(6414): 536–542 https://doi.org/10.1126/science.aat9072
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C Fu, Z Li, Z Sun, S Xie. A review of salting-out effect and sugaring-out effect: driving forces for novel liquid-liquid extraction of biofuels and biochemicals. Frontiers of Chemical Science and Engineering, 2020, doi: 10.1007/s11705-020-1980-3
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R Zhou, R Zhou, S Wang, U G Mihiri Ekanayake, Z Fang, P J Cullen, K Bazaka, K K Ostrikov. Power-to-chemicals: low-temperature plasma for lignin depolymerisation in ethanol. Bioresource Technology, 2020, 318: 123917 https://doi.org/10.1016/j.biortech.2020.123917
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Y Xue, B Gao, Y Yao, M Inyang, M Zhang, A R Zimmerman, K S Ro. Hydrogen peroxide modification enhances the ability of biochar (hydrochar) produced from hydrothermal carbonization of peanut hull to remove aqueous heavy metals: batch and column tests. Chemical Engineering Journal, 2012, 200-202: 673–680 https://doi.org/10.1016/j.cej.2012.06.116
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G X Yang, H Jiang. Amino modification of biochar for enhanced adsorption of copper ions from synthetic wastewater. Water Research, 2014, 48: 396–405 https://doi.org/10.1016/j.watres.2013.09.050
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Y Zhong, P Zhang, X Zhu, H Li, Q Deng, J Wang, Z Zeng, J J Zou, S Deng. Highly efficient alkylation using hydrophobic sulfonic acid-functionalized biochar as a catalyst for synthesis of high-density biofuels. ACS Sustainable Chemistry & Engineering, 2019, 7(17): 14973–14981 https://doi.org/10.1021/acssuschemeng.9b03190
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R K Gupta, M Dubey, P Kharel, Z Gu, Q H Fan. Biochar activated by oxygen plasma for supercapacitors. Journal of Power Sources, 2015, 274: 1300–1305 https://doi.org/10.1016/j.jpowsour.2014.10.169
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R Zhou, R Zhou, X Zhang, K Bazaka, K K Ostrikov. Continuous flow removal of acid fuchsine by dielectric barrier discharge plasma water bed enhanced by activated carbon adsorption. Frontiers of Chemical Science and Engineering, 2019, 13(2): 340–349 https://doi.org/10.1007/s11705-019-1798-z
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E C Neyts. Special Issue on future directions in plasma nanoscience. Frontiers of Chemical Science and Engineering, 2019, 13(2): 199–200 https://doi.org/10.1007/s11705-019-1843-y
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X Wang, R Zhou, C Zhang, S Xi, M W M Jones, T Tesfamichael, A Du, K Gui, K K Ostrikov, H Wang. Plasma-induced on-surface sulfur vacancies in NiCo2S4 enhance the energy storage performance of supercapatteries. Journal of Materials Chemistry. A, Materials for Energy and Sustainability, 2020, 8(18): 9278–9291 https://doi.org/10.1039/D0TA01991G
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R Zhou, R Zhou, Y Xian, Z Fang, X Lu, K Bazaka, A Bogaerts, K K Ostrikov. Plasma-enabled catalyst-free conversion of ethanol to hydrogen gas and carbon dots near room temperature. Chemical Engineering Journal, 2020, 382: 112745 https://doi.org/10.1016/j.cej.2019.122745
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Y Xin, B Sun, X Zhu, Z Yan, X Zhao, X Sun. Hydrogen production from ethanol decomposition by pulsed discharge with needle-net configurations. Applied Energy, 2017, 206: 126–133 https://doi.org/10.1016/j.apenergy.2017.08.055
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Y Xin, B Sun, X Zhu, Z Yan, X Zhao, X Sun. Carbon nanoparticles production by pulsed discharge in liquid alcohols. Vacuum, 2018, 151: 90–95 https://doi.org/10.1016/j.vacuum.2018.02.006
T Zhao, N Ullah, Y Hui, Z Li. Review of plasma-assisted reactions and potential applications for modification of metal-organic frameworks. Frontiers of Chemical Science and Engineering, 2019, 13(3): 444–457 https://doi.org/10.1007/s11705-019-1811-6
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R Zhou, R Zhou, D Alam, T Zhang, W Li, Y Xia, A Mai-Prochnow, H An, E C Lovell, H Masood, R Amal, K K Ostrikov, P J Cullen. Plasmacatalytic bubbles using CeO2 for organic pollutant degradation. Chemical Engineering Journal, 2021, 403: 126413 https://doi.org/10.1016/j.cej.2020.126413
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L Ye, J Zhang, J Zhao, Z Luo, S Tu, Y Yin. Properties of biochar obtained from pyrolysis of bamboo shoot shell. Journal of Analytical and Applied Pyrolysis, 2015, 114: 172–178 https://doi.org/10.1016/j.jaap.2015.05.016
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O Kazak, Y R Eker, H Bingol, A Tor. Novel preparation of activated carbon by cold oxygen plasma treatment combined with pyrolysis. Chemical Engineering Journal, 2017, 325: 564–575 https://doi.org/10.1016/j.cej.2017.05.107
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K S Siow, S Kumar, H J Griesser. Low-pressure plasma methods for generating non-reactive hydrophilic and hydrogel-like bio-interface coatings—a review. Plasma Processes and Polymers, 2015, 12(1): 8–24 https://doi.org/10.1002/ppap.201400116
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B Zhang, P Xu, Y Qiu, Q Yu, J Ma, H Wu, G Luo, M Xu, H Yao. Increasing oxygen functional groups of activated carbon with non-thermal plasma to enhance mercury removal efficiency for flue gases. Chemical Engineering Journal, 2015, 263: 1–8 https://doi.org/10.1016/j.cej.2014.10.090
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B Peng, R Zhou, Y Chen, S Tu, Y Yin, L Ye. Immobilization of nano-zero-valent irons by carboxylated cellulose nanocrystals for wastewater remediation. Frontiers of Chemical Science and Engineering, 2020, 14(6): 1006–1072 https://doi.org/10.1007/s11705-020-1924-y
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L Ouni, A Ramazani, S T Fardood. An overview of carbon nanotubes role in heavy metals removal from wastewater. Frontiers of Chemical Science and Engineering, 2019, 13(2): 1–22 https://doi.org/10.1007/s11705-018-1765-0
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F Wang, Y Pan, P Cai, T Guo, H Xiao. Single and binary adsorption of heavy metal ions from aqueous solutions using sugarcane cellulose-based adsorbent. Bioresource Technology, 2017, 241: 482–490 https://doi.org/10.1016/j.biortech.2017.05.162
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U Thubsuang, S Chotirut, A Thongnok, A Promraksa, M Nisoa, N Manmuanpom, S Wongkasemjit, T Chaisuwan. Facile preparation of polybenzoxazine-based carbon microspheres with nitrogen functionalities: effects of mixed solvents on pore structure and supercapacitive performance. Frontiers of Chemical Science and Engineering, 2020, 14(6): 1072–1086 https://doi.org/10.1007/s11705-019-1899-8
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R Zhou, R Zhou, X Zhang, Z Fang, X Wang, R Speight, H Wang, W Doherty, P J Cullen, K K Ostrikov, K Bazaka. High-performance plasma-enabled biorefining of microalgae to value-added products. ChemSusChem, 2019, 12(22): 4976–4985 https://doi.org/10.1002/cssc.201901772
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