[1]

Abdullah N, Mohd Taib R, Mohamad Aziz NS, Omar MR, Md Disa N. 2023. Banana pseudo-stem biochar derived from slow and fast pyrolysis process. Heliyon 9:e12940

doi: 10.1016/j.heliyon.2023.e12940
[2]

Guo J, Xiao H, Zhang JB, Dai C, Li T, et al. 2024. Characterization of highly stable biochar and its application for removal of phenol. Biomass Conversion and Biorefinery 14:13311−13321

doi: 10.1007/s13399-022-03375-3
[3]

Han KH, Yun SI, Choi DH, Lee SI. 2024. Net CO2 removal of rice husk biochar as soil amendment depending on energy reuse in the production stage. Korean Journal of Soil Science and Fertilizer 57:130−139

doi: 10.7745/KJSSF.2024.57.2.130
[4]

Lin M, Li F, Li X, Rong X, Oh K. 2023. Biochar-clay, biochar-microorganism and biochar-enzyme composites for environmental remediation: a review. Environmental Chemistry Letters 21:1837−1862

doi: 10.1007/s10311-023-01582-6
[5]

Luo K, Pang Y, Wang D, Li X, Wang L, et al. 2021. A critical review on the application of biochar in environmental pollution remediation: role of persistent free radicals (PFRs). Journal of Environmental Sciences 108:201−216

doi: 10.1016/j.jes.2021.02.021
[6]

Lian F, Xing B. 2017. Black carbon (biochar) in water/soil environments: molecular structure, sorption, stability, and potential risk. Environmental Science & Technology 51:13517−13532

doi: 10.1021/acs.est.7b02528
[7]

Zhang X, Wei F, Fu H, Guo H. 2025. Characterisation of environmentally persistent free radicals and their contributions to oxidative potential and reactive oxygen species in sea spray and size-resolvedambient particles. npj Climate and Atmospheric Science 8:27

doi: 10.1038/s41612-025-00911-6
[8]

Zhang Y, Xu M, Liu X, Wang M, Zhao J, et al. 2021. Regulation of biochar mediated catalytic degradation of quinolone antibiotics: important role of environmentally persistent free radicals. Bioresource Technology 326:124780

doi: 10.1016/j.biortech.2021.124780
[9]

Liu X, Chen Z, Lu S, Shi X, Qu F, et al. 2024. Persistent free radicals on biochar for its catalytic capability: a review. Water Research 250:120999

doi: 10.1016/j.watres.2023.120999
[10]

Xie L, Zhu K, Chen N, Deng Y, Jiang W, et al. 2024. A critical review of an environmental risk substance induced by aging microplastics: insights into environmentally persistent free radicals. Environmental Science & Technology 58:22502−22518

doi: 10.1021/acs.est.4c09107
[11]

Yang H, Chen N, Wang Z, Liu J, Qin J, et al. 2023. Biochar-associated free radicals reduce soil bacterial diversity: new insight into ecoenzymatic stoichiometry. Environmental Science & Technology 57:20238−20248

doi: 10.1021/acs.est.3c06864
[12]

Huang Y, Guo X, Ding Z, Chen Y, Hu X. 2020. Environmentally persistent free radicals in biochar derived from Laminaria japonica grown in different habitats. Journal of Analytical and Applied Pyrolysis 151:104941

doi: 10.1016/j.jaap.2020.104941
[13]

Bi D, Huang F, Jiang M, He Z, Lin X. 2022. Effect of pyrolysis conditions on environmentally persistent free radicals (EPFRs) in biochar from co-pyrolysis of urea and cellulose. Science of the Total Environment 805:150339

doi: 10.1016/j.scitotenv.2021.150339
[14]

Xiang C, Liu Q, Shi L, Liu Z. 2020. A study on the new type of radicals in corncob derived biochars. Fuel 277:118163

doi: 10.1016/j.fuel.2020.118163
[15]

Tao W, Zhang P, Li H, Yang Q, Oleszczuk P, et al. 2022. Generation mechanism of persistent free radicals in lignocellulose-derived biochar: roles of reducible carbonyls. Environmental Science & Technology 56:10638−10645

doi: 10.1021/acs.est.1c06997
[16]

Chen D, Xu J, Ling P, Fang Z, Ren Q, et al. 2024. Formation and evolution mechanism of persistent free radicals in biochar during biomass pyrolysis: insights from biochar's element composition and chemical structure. Fuel 357:129910

doi: 10.1016/j.fuel.2023.129910
[17]

Franklin J. 2005. The elements of statistical learning: data mining, inference and prediction. The Mathematical Intelligencer 27:83−85

doi: 10.1007/BF02985802
[18]

Hutengs C, Vohland M. 2016. Downscaling land surface temperatures at regional scales with random forest regression. Remote Sensing of Environment 178:127−141

doi: 10.1016/j.rse.2016.03.006
[19]

Deng R, Luo H, Huang D, Zhang C. 2020. Biochar-mediated Fenton-like reaction for the degradation of sulfamethazine: role of environmentally persistent free radicals. Chemosphere 255:126975

doi: 10.1016/j.chemosphere.2020.126975
[20]

Fang G, Zhu C, Dionysiou DD, Gao J, Zhou D. 2015. Mechanism of hydroxyl radical generation from biochar suspensions: implications to diethyl phthalate degradation. Bioresource Technology 176:210−217

doi: 10.1016/j.biortech.2014.11.032
[21]

Huang D, Luo H, Zhang C, Zeng G, Lai C, et al. 2019. Nonnegligible role of biomass types and its compositions on the formation of persistent free radicals in biochar: insight into the influences on Fenton-like process. Chemical Engineering Journal 361:353−363

doi: 10.1016/j.cej.2018.12.098
[22]

Zhu Z, Gou Q, Duan W, Chen F, Steinberg CEW, et al. 2025. Biochar-mediated degradation of p-nitrophenol as influenced by species of Fe(III). Biochar 7:65

doi: 10.1007/s42773-025-00448-0
[23]

Baltrėnaitė-Gedienė E, Lomnicki S, Guo C. 2022. Impact of biochar, fertilizers and cultivation type on environmentally persistent free radicals in agricultural soil. Environmental Technology & Innovation 28:102755

doi: 10.1016/j.eti.2022.102755
[24]

Baltrėnaitė-Gedienė E, Lomnicki S, Ogunmusi O. 2024. Research of the impact of environmentally persistent free radicals on chemical element behaviour in the soil-plant system. Chemosphere 364:143088

doi: 10.1016/j.chemosphere.2024.143088
[25]

Bao D, Li Z, Tang R, Wan C, Zhang C, et al. 2021. Metal-modified sludge-based biochar enhance catalytic capacity: characteristics and mechanism. Journal of Environmental Management 284:112113

doi: 10.1016/j.jenvman.2021.112113
[26]

Bi D, Yin M, Huang F, Zhang J, Yi W. 2023. Evolution and prediction model of environmentally-persistent free radicals in biomass three-component pyrolytic carbon with pyrolysis temperature. Industrial Crops and Products 206:117643

doi: 10.1016/j.indcrop.2023.117643
[27]

Cheng Y, Lu K, Chen Z, Li N, Wang M. 2024. Biochar reduced the risks of human bacterial pathogens in soil via disturbing quorum sensing mediated by persistent free radicals. Environmental Science & Technology 58:22343−22354

doi: 10.1021/acs.est.4c07668
[28]

Gao Y, Gao Y, Li A. 2025. Effect mechanism of H3PO4 on the formation and transformation of persistent free radicals in biochar. Biochar 7:28

doi: 10.1007/s42773-024-00405-3
[29]

Hu Y, Tong K, Guo Q, Zhang B, Jiao L, et al. 2022. Effect of controlled temperature and biomass addition on the formed environmental persistent free radicals (EPFRs) in sewage sludge-based biochar from pyrolysis treatment. Journal of Analytical and Applied Pyrolysis 162:105460

doi: 10.1016/j.jaap.2022.105460
[30]

Hu Y, Zhang B, Guo Q, Wang S, Lu S. 2022. Characterization into environmentally persistent free radicals formed in incineration fly ash and pyrolysis biochar of sewage sludge and biomass. Journal of Cleaner Production 373:133666

doi: 10.1016/j.jclepro.2022.133666
[31]

Wang Y, Gu X, Huang Y, Ding Z, Chen Y, et al. 2022. Insight into biomass feedstock on formation of biochar-bound environmentally persistent free radicals under different pyrolysis temperatures. RSC Advances 12:19318−19326

doi: 10.1039/d2ra03052g
[32]

Xuchao Z, Yi C, Die H, Li Z, Lin W, et al. 2019. Neurotoxic effect of environmental persistent free radicals in rice biochar to Caenorhabditis elegans. China Environmental Science 39:2644−2651

doi: 10.19674/j.cnki.issn1000-6923.2019.0314
[33]

Yan X, Cao T, Chen H, Wu J, Xu C, et al. 2025. Formation and evolution of environmentally persistent free radicals in charcoal and soot generated from biomass materials. Journal of Hazardous Materials 488:137523

doi: 10.1016/j.jhazmat.2025.137523
[34]

Zhao J, Shen G, Shi L, Li H, Lang D, et al. 2022. Real-world emission characteristics of environmentally persistent free radicals in PM2.5 from residential solid fuel combustion. Environmental Science & Technology 56:3997−4004

doi: 10.1021/acs.est.1c08449
[35]

Zhong D, Zhang Y, Wang L, Chen J, Jiang Y, et al. 2018. Mechanistic insights into adsorption and reduction of hexavalent chromium from water using magnetic biochar composite: key roles of Fe3O4 and persistent free radicals. Environmental Pollution 243:1302−1309

doi: 10.1016/j.envpol.2018.08.093
[36]

Xiao X, Chen Z, Chen B. 2016. H/C atomic ratio as a smart linkage between pyrolytic temperatures, aromatic clusters and sorption properties of biochars derived from diverse precursory materials. Scientific Reports 6:22644

doi: 10.1038/srep22644
[37]

Fang G, Liu C, Gao J, Dionysiou DD, Zhou D. 2015. Manipulation of persistent free radicals in biochar to activate persulfate for contaminant degradation. Environmental Science & Technology 49:5645−5653

doi: 10.1021/es5061512
[38]

Hasan F, Khachatryan L, Lomnicki S. 2020. Comparative studies of environmentally persistent free radicals on total particulate matter collected from electronic and tobacco cigarettes. Environmental Science & Technology 54:5710−5718

doi: 10.1021/acs.est.0c00351
[39]

Tang Z, Zhao S, Qian Y, Jia H, Gao P, et al. 2021. Formation of persistent free radicals in sludge biochar by hydrothermal carbonization. Environmental Chemistry Letters 19:2705−2712

doi: 10.1007/s10311-021-01198-8
[40]

Tay HL, Kajitani S, Zhang S, Li CZ. 2013. Effects of gasifying agent on the evolution of char structure during the gasification of Victorian brown coal. Fuel 103:22−28

doi: 10.1016/j.fuel.2011.02.044
[41]

Ruan X, Liu Y, Wang G, Frost RL, Qian G, et al. 2018. Transformation of functional groups and environmentally persistent free radicals in hydrothermal carbonisation of lignin. Bioresource Technology 270:223−229

doi: 10.1016/j.biortech.2018.09.027
[42]

Vejerano EP, Rao G, Khachatryan L, Cormier SA, Lomnicki S. 2018. Environmentally persistent free radicals: insights on a new class of pollutants. Environmental Science & Technology 52:2468−2481

doi: 10.1021/acs.est.7b04439