Effect of different climate zone’s humic and fulvic acid on aggregation of UV irradiated graphene oxide

Highlights

	● GO converted to rGO with less hydrophilicity after 2 h UV irradiation.
	● UV irradiated GO aggregated more with different climate zone’s FA than HA.
	● Physicochemical properties of HA/FA had obvious effect on UV-aged GO aggregation.
	● C–C/C=C and C–O functional groups involved in GO’s stability/aggregation.

Abstract

UV light absorption by aquatic systems affect the physicochemical characteristics of graphene oxide (GO) nanoparticles which ultimately influence its aggregation behavior in water. Regarding this research, various humic and fulvic acids (HA/FA), extracted from China’s different climate zones, were treated with 2 h UV irradiated large (~500 nm) and (~200 nm) GO in 200 mmol/L NaCl. UV irradiated GO particles displayed aggregation even at low humic acid/fulvic acid (HA/FA) concentrations ranging from 0.2 to 1.0 mgC/L, whereas pristine GO particles did not exhibit such behavior. Reduction of functional groups, containing Oxygen (C=O/C–O), via UV irradiation is responsible for this aggregation phenomenon and conversion of GO to reduced graphene oxide (rGO). Consequently, rGO exhibits lower dispersibility, facilitating its agglomeration. Moreover, both small and large-sized GO particles exhibited less aggregation in HAs compared to FAs due to large molecular weight and high polarity of HAs. Aggregation of GO was more obvious with Makou FA and Maqin HA from Plateau and Mountain climate zone and Subtropical Monsoon climate zone, respectively, owing to DOM’s lower molecular weight and aromaticity that reduced their adsorption. The application of the Derjaguin-landau-verwey-overbeek (DLVO) theory did not reveal any significant interaction energy barrier between the 2 h UV irradiated GO particles even in the presence of DOM, indicating that aggregation prevailed despite the addition of DOM. These findings highlight that UV irradiation poses a significant threat to the GO stability in aquatic environments, particularly in the presence of DOM.

Graphical abstract

Keywords

Aggregation / Fulvic acid / Humic acid / Molecular weight / Reduced graphene oxide / Ultraviolet irradiation

References

[1] Adegboyega N F, Sharma V K, Siskova K, Zbořil R, Sohn M, Schultz B J, Banerjee S. (2013). Interactions of aqueous Ag⁺ with fulvic acids: mechanisms of silver nanoparticle formation and investigation of stability. Environmental Science & Technology, 47(2): 757–764

[2] Adeleye A S, Conway J R, Garner K, Huang Y, Su Y, Keller A A. (2016). Engineered nanomaterials for water treatment and remediation: Costs, benefits, and applicability. Chemical Engineering Journal, 286: 640–662

[3] Ali J, Li Y, Shang E, Wang X, Zhao J, Mohiuddin M, Xia X. (2023a). Aggregation of graphene oxide and its environmental implications in the aquatic environment. Chinese Chemical Letters, 34(2): 107327

[4] Ali J, Li Y, Wang X, Zhao J, Xi N, Zhang Z, Xia X. (2020). Climate-zone-dependent effect mechanism of humic acid and fulvic acid extracted from river sediments on aggregation behavior of graphene oxide. Science of the Total Environment, 721: 137682

[5] Ali J, Wang X, Shang E, Wang Y, Zhao J, Gao B, Xia X, Li Y. (2023b). Promotion effect of ultraviolet light on graphene oxide aggregation in the presence of different climatic zone’s humic and fulvic acid. Water Research, 242: 120261

[6] Amaro-Gahete J, Benítez A, Otero R, Esquivel D, Jiménez-Sanchidrián C, Morales J, Caballero Á, Romero-Salguero F J. (2019). A comparative study of particle size distribution of graphene nanosheets synthesized by an ultrasound-assisted method. Nanomaterials (Basel, Switzerland), 9(2): 152

[7] Andryushina N S, Stroyuk O L, Yanchuk I B, Yefanov A V. (2014). A dynamic light scattering study of photochemically reduced colloidal graphene oxide. Colloid & Polymer Science, 292(2): 539–546

[8] Chowdhury I, Duch M C, Mansukhani N D, Hersam M C, Bouchard D. (2013). Colloidal properties and stability of graphene oxide nanomaterials in the aquatic environment. Environmental Science & Technology, 47(12): 6288–6296

[9] Chowdhury I, Hou W C, Goodwin D, Henderson M, Zepp R G, Bouchard D. (2015a). Sunlight affects aggregation and deposition of graphene oxide in the aquatic environment. Water Research, 78: 37–46

[10] Chowdhury I, Mansukhani N D, Guiney L M, Hersam M C, Bouchard D. (2015b). Aggregation and stability of reduced graphene oxide: complex roles of divalent cations, pH, and natural organic matter. Environmental Science & Technology, 49(18): 10886–10893

[11] CrittendenJ C, TrussellR R, HandD W, HoweK J, Tchobanoglous G (2012). MWH’s Water Treatment: Principles and Design. 3rd ed. Hoboken: John Wiley & Sons

[12] Ding G, Zhang N, Wang C, Li X, Zhang J, Li W, Li R, Yang Z. (2018). Effect of the size on the aggregation and sedimentation of graphene oxide in seawaters with different salinities. Journal of Nanoparticle Research, 20(11): 313

[13] Du T, Adeleye A S, Zhang T, Jiang C, Zhang M, Wang H, Li Y, Keller A A, Chen W. (2018). Influence of light wavelength on the photoactivity, physicochemical transformation, and fate of graphene oxide in aqueous media. Environmental Science. Nano, 5(11): 2590–2603

[14] Engel M, Chefetz B. (2019). The missing link between carbon nanotubes, dissolved organic matter and organic pollutants. Advances in Colloid and Interface Science, 271: 101993

[15] Gacka E, Majchrzycki Ł, Marciniak B, Lewandowska-Andralojc A. (2021). Effect of graphene oxide flakes size and number of layers on photocatalytic hydrogen production. Scientific Reports, 11(1): 15969

[16] Gallegos-Pérez W R, Reynosa-Martínez A C, Soto-Ortiz C, Angélica Álvarez-Lemus M, Barroso-Flores J, García Montalvo V, López-Honorato E. (2020). Effect of UV radiation on the structure of graphene oxide in water and its impact on cytotoxicity and As(III) adsorption. Chemosphere, 249: 126160

[17] Gao Y, Ren X, Zhang X, Chen C. (2019). Environmental fate and risk of ultraviolet-and visible-light-transformed graphene oxide: a comparative study. Environmental Pollution, 251: 821–829

[18] Gao Y, Zeng X, Zhang W, Zhou L, Xue W, Tang M, Sun S. (2022). The aggregation behaviour and mechanism of commercial graphene oxide in surface aquatic environments. Science of the Total Environment, 806: 150942

[19] Guardia L, Villar-Rodil S, Paredes J, Rozada R, Martínez-Alonso A, Tascón J. (2012). UV light exposure of aqueous graphene oxide suspensions to promote their direct reduction, formation of graphene–metal nanoparticle hybrids and dye degradation. Carbon, 50(3): 1014–1024

[20] Hartley I P, Hill T C, Chadburn S E, Hugelius G. (2021). Temperature effects on carbon storage are controlled by soil stabilisation capacities. Nature Communications, 12(1): 6713

[21] He K, Chen G, Zeng G, Peng M, Huang Z, Shi J, Huang T. (2017). Stability, transport and ecosystem effects of graphene in water and soil environments. Nanoscale, 9(17): 5370–5388

[22] He Y T, Wan J, Tokunaga T. (2008). Kinetic stability of hematite nanoparticles: the effect of particle sizes. Journal of Nanoparticle Research, 10(2): 321–332

[23] Hou W C, Chowdhury I, Goodwin D G Jr, Henderson W M, Fairbrother D H, Bouchard D, Zepp R G. (2015). Photochemical transformation of graphene oxide in sunlight. Environmental Science & Technology, 49(6): 3435–3443

[24] Hu A, Choi M, Tanentzap A J, Liu J, Jang K S, Lennon J T, Liu Y, Soininen J, Lu X, Zhang Y. . (2022). Ecological networks of dissolved organic matter and microorganisms under global change. Nature Communications, 13(1): 3600

[25] Hu L, Cui J, Lu T, Wang Y, Jia J. (2024). Triple signal amplification electrochemical sensing platform for Hg²⁺ in water without direct modification of the working electrode. Frontiers of Environmental Science & Engineering, 18(7): 90

[26] Hu X, Zhou M, Zhou Q. (2015). Ambient water and visible-light irradiation drive changes in graphene morphology, structure, surface chemistry, aggregation, and toxicity. Environmental Science & Technology, 49(6): 3410–3418

[27] Hua Z, Zhang J, Bai X, Ye Z, Tang Z, Liang L, Liu Y. (2016). Aggregation of TiO₂–graphene nanocomposites in aqueous environment: Influence of environmental factors and UV irradiation. Science of the Total Environment, 539: 196–205

[28] Kim C, Lee J, Wang W, Fortner J. (2020). Organic functionalized graphene oxide behavior in water. Nanomaterials (Basel, Switzerland), 10(6): 1228

[29] Ko K, Kim M J, Lee J Y, Kim W, Chung H J. (2019). Effects of graphene oxides and silver-graphene oxides on aquatic microbial activity. Science of the Total Environment, 651: 1087–1095

[30] Lanphere J D, Luth C J, Walker S L. (2013). Effects of solution chemistry on the transport of graphene oxide in saturated porous media. Environmental Science & Technology, 47(9): 4255–4261

[31] Lanphere J D, Rogers B, Luth C, Bolster C H, Walker S L. (2014). Stability and transport of graphene oxide nanoparticles in groundwater and surface water. Environmental Engineering Science, 31(7): 350–359

[32] Lee B M, Seo Y S, Hur J. (2015). Investigation of adsorptive fractionation of humic acid on graphene oxide using fluorescence EEM-PARAFAC. Water Research, 73: 242–251

[33] Li Y, Niu J, Shang E, Crittenden J C. (2015). Synergistic photogeneration of reactive oxygen species by dissolved organic matter and C₆₀ in aqueous phase. Environmental Science & Technology, 49(2): 965–973

[34] Liu Y, Hu Y, Yang C, Chen C, Huang W, Dang Z. (2019). Aggregation kinetics of UV irradiated nanoplastics in aquatic environments. Water Research, 163: 114870

[35] Mattsson T, Kortelainen P, Räike A. (2005). Export of DOM from boreal catchments: impacts of land use cover and climate. Biogeochemistry, 76(2): 373–394

[36] Minor E, Stephens B. (2008). Dissolved organic matter characteristics within the Lake Superior watershed. Organic Geochemistry, 39(11): 1489–1501

[37] Mozaffarpour F, Hassanzadeh N, Vahidi E. (2023). Synthesis, characterization and life cycle assessment of electrochemically exfoliated KOH-activated holey graphene. Frontiers of Environmental Science & Engineering, 17(12): 155

[38] Mulyana Y, Uenuma M, Ishikawa Y, Uraoka Y. (2014). Reversible oxidation of graphene through ultraviolet/ozone treatment and its nonthermal reduction through ultraviolet irradiation. Journal of Physical Chemistry C, 118(47): 27372–27381

[39] Pang Y, Hammer T, Müller D, Karl J. (2019). Investigation of nonthermal plasma assisted charcoal gasification for production of hydrogen-rich syngas. Processes (Basel, Switzerland), 7(2): 114

[40] Park C M, Wang D, Heo J, Her N, Su C. (2018). Aggregation of reduced graphene oxide and its nanohybrids with magnetite and elemental silver under environmentally relevant conditions. Journal of Nanoparticle Research, 20: 93

[41] Qi Z, Du T, Ma P, Liu F, Chen W. (2019). Transport of graphene oxide in saturated quartz sand containing iron oxides. Science of the Total Environment, 657: 1450–1459

[42] Qiu Y, Wang Z, Owens A C E, Kulaots I, Chen Y, Kane A B, Hurt R H. (2014). Antioxidant chemistry of graphene-based materials and its role in oxidation protection technology. Nanoscale, 6(20): 11744–11755

[43] Qu X, Brame J, Li Q, Alvarez P J. (2013). Nanotechnology for a safe and sustainable water supply: enabling integrated water treatment and reuse. Accounts of Chemical Research, 46(3): 834–843

[44] Rana S, Kaur R, Jain R, Prabhakar N. (2019). Ionic liquid assisted growth of poly (3, 4-ethylenedioxythiophene)/reduced graphene oxide based electrode: An improved electro-catalytic performance for the detection of organophosphorus pesticides in beverages. Arabian Journal of Chemistry, 12(7): 1121–1133

[45] Ren X, Li J, Chen C, Gao Y, Chen D, Su M, Alsaedi A, Hayat T. (2018). Graphene analogues in aquatic environments and porous media: dispersion, aggregation, deposition and transformation. Environmental Science. Nano, 5(6): 1298–1340

[46] Shams M, Guiney L M, Huang L, Ramesh M, Yang X, Hersam M C, Chowdhury I. (2019). Influence of functional groups on the degradation of graphene oxide nanomaterials. Environmental Science. Nano, 6(7): 2203–2214

[47] Shen M, Hai X, Shang Y, Zheng C, Li P, Li Y, Jin W, Li D, Li Y, Zhao J. . (2019). Insights into aggregation and transport of graphene oxide in aqueous and saturated porous media: Complex effects of cations with different molecular weight fractionated natural organic matter. Science of the Total Environment, 656: 843–851

[48] Singh V, Rai V K, Ledoux-Rak I, Watanabe S, Gundu Rao T K, Chubaci J F D, Badie L, Pelle F, Ivanova S. (2009). NIR to visible up-conversion, infrared luminescence, thermoluminescence and defect centres in Y₂O₃ : Er phosphor. Journal of Physics. D, Applied Physics, 42(6): 065104

[49] Song Y K, Hong S H, Jang M, Han G M, Jung S W, Shim W J. (2017). Combined effects of UV exposure duration and mechanical abrasion on microplastic fragmentation by polymer type. Environmental Science & Technology, 51(8): 4368–4376

[50] Spilarewicz-Stanek K, Jakimińska A, Kisielewska A, Dudek M, Piwoński I. (2021). Graphene oxide photochemical transformations induced by UV irradiation during photocatalytic processes. Materials Science in Semiconductor Processing, 123: 105525

[51] Szabo T, Maroni P, Szilagyi I. (2020). Size-dependent aggregation of graphene oxide. Carbon, 160: 145–155

[52] Tada D B, Baptista M S. (2015). Photosensitizing nanoparticles and the modulation of ROS generation. Frontiers in Chemistry, 3: 33

[53] TadrosT (2007). General Principles of Colloid Stability and the Role of Surface Forces. Weinheim: Wiley Online Library, 1–22

[54] Tang H, Zhang S, Huang T, Cui F, Xing B. (2020). Effects of pH and electrolytes on the sheet-to-sheet aggregation mode of graphene oxide in aqueous solutions. Environmental Science. Nano, 7(3): 984–995

[55] Tang X, Luo J, Wang L, Li X. (2021). Effect of water chemistry on the uptake of Co(II) on graphene oxide investigated by batch technique. Nature Environment and Pollution Technology, 20(3): 909–922

[56] Trefalt G, Behrens S H, Borkovec M. (2016). Charge regulation in the electrical double layer: Ion adsorption and surface interactions. Langmuir, 32(2): 380–400

[57] Varodi C, Coros M, Pogăcean F, Ciorîţă A, Turza A, Pruneanu S. (2022). Nitrogen-doped graphene-based sensor for electrochemical detection of piroxicam, a NSAID drug for COVID-19 patients. Chemosensors (Basel, Switzerland), 10(2): 47

[58] Wang K, Jiang L, Wu X, Zhang G. (2020a). Vacancy mediated Z-scheme charge transfer in a 2D/2D La₂Ti₂O₇/g-C₃N₄ nanojunction as a bifunctional photocatalyst for solar-to-energy conversion. Journal of Materials Chemistry. A, 8(26): 13241–13247

[59] Wang T, Wen J, Guo S, Mu L. (2020b). Hypochlorite and visible-light irradiation affect the transformation and toxicity of graphene oxide. Science of the Total Environment, 723: 138010

[60] Wang X, Li Y, Zhao J, Xia X, Shi X, Duan J, Zhang W. (2020c). UV-induced aggregation of polystyrene nanoplastics: effects of radicals, surface functional groups and electrolyte. Environmental Science. Nano, 7(12): 3914–3926

[61] Wang X, Zhang H, Wang X, Chen S, Yu H, Quan X. (2023). Electroconductive RGO-MXene membranes with wettability-regulated channels: improved water permeability and electro-enhanced rejection performance. Frontiers of Environmental Science & Engineering, 17(1): 1

[62] Waychunas G A, Kim C S, Banfield J F. (2005). Nanoparticulate iron oxide minerals in soils and sediments: unique properties and contaminant scavenging mechanisms. Journal of Nanoparticle Research, 7(4−5): 409–433

[63] Wu X, Liu P, Gong Z, Wang H, Huang H, Shi Y, Zhao X, Gao S. (2021). Humic acid and fulvic acid hinder long-term weathering of microplastics in lake water. Environmental Science & Technology, 55(23): 15810–15820

[64] Xia P, Zhang W, Jin Q, Si J, Guo F, Li Z, Bai Y. (2023). Influence of fulvic acid sub-fractions on aggregation kinetics of graphene oxide in aqueous environments. Science of the Total Environment, 860: 160318

[65] Xu Y, Ou Q, Li X, Wang X, Van Der Hoek J P, Liu G. (2022). Combined effects of photoaging and natural organic matter on the colloidal stability of nanoplastics in aquatic environments. Water Research, 226: 119313

[66] Yoo J, Lee S M, Lee K, Lim S C, Jeong M S, Kim J, Lee T G. (2023). Functional group inhomogeneity in graphene oxide using correlative absorption spectroscopy. Applied Surface Science, 613: 155885

[67] Yuan X, Peng D, Jing Q, Niu J, Cheng X, Feng Z, Wu X. (2018). Green and effective removal of aqueous graphene oxide under UV-light irradiation. Nanomaterials, 8(9): 654

[68] Zhang D, Yan S, Song W. (2014). Photochemically induced formation of reactive oxygen species (ROS) from effluent organic matter. Environmental Science & Technology, 48(21): 12645–12653

Acknowledgements

This study was financially supported by the National Natural Science Foundation of China (Nos. 42250410319, 52170024 and 21677015), the Qingdao Municipal Bureau of Human Resources and Social Security, China (No. QDBSH20220201006).

Conflict Interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Electronic Supplementary Material

Supplementary material is available in the online version of this article at https://doi.org/10.1007/s11783-025-1948-0 and is accessible for authorized users.

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