TY - JOUR

T1 - Palygorskite supported nanometer spherical Fe2O3 composite as an effective photocatalyst for peroxymonosulfate activation: Promotion of the Fe(III)/Fe(II) cycle by photogenerated electrons under visible light

AU - Tang, Huiling

AU - Xu, Yin

AU - Tang, Weiping

AU - Xiao, Yan

AU - Zhang, Chi

AU - Xu, Jing

AU - Pozdnyakov, Ivan P.

AU - Zhang, Hui

N1 - This work is supported by the National Natural Science Foundation of China (Grant No. 22061132001 ) and Russian Science Foundation (Grant RSF- NSFC No. 21-43-00004 ). We would like to express our appreciation for Professor Gates\u2019 inspiration and his impact on our environmental chemical engineering career.

PY - 2024/9/15

Y1 - 2024/9/15

N2 - In this work, a well-known efficient catalyst nanosphere Fe2O3 has been loaded on the palygorskite to improve its dispersibility. A series of Fe2O3/palygorskite (FOP) were obtained and first used for peroxymonosulfate (PMS) activation to remove bisphenol A (BPA) under visible light (Vis, λ ≥ 400 nm). The FOP-2.0 prepared with a loading ratio of 2.0 g Fe(NO3)3·9H2O per g of palygorskite exhibits excellent catalytic performance for pollutant removal. Under the optimal conditions of 0.8 g L−1 FOP-2.0, 1.0 mM PMS and neutral pH, 90.3 % of 0.05 mM BPA was removed in the presence of 300 W Xenon lamp light within 60 min reaction time. To comprehensively investigate the underlying mechanism of Vis/FOP-2.0/PMS system, chemical quenching experiment, electron paramagnetic resonance (EPR) technique, electrochemical test and X-ray photoelectron spectroscopy (XPS) analysis were conducted in FOP-2.0/PMS system with or without visible light irradiation. Surface-bound sulfate and hydroxyl radicals were revealed to be the primary reactive species in the dark system, which proliferated with the introduction of visible light, thanks to the fact that the photogenerated electrons (e−) accelerated the redox cycle of Fe(III)/Fe(II) towards PMS activation. Additionally, photogenerated holes and a very small amount of free radicals participated in BPA abatement in the Vis/FOP-2.0/PMS system. The practicability of Vis/FOP-2.0/PMS system was further validated by applying natural sunlight irradiation, treating various pollutants and investigating the interference of coexisting anions as well as the recycling use performance in water. Overall, this work sheds light on the design of green, efficient and low-cost heterogeneous photocatalysts and provides new insight into the mechanism regarding the enhancement of photocatalytic activity by visible light.

AB - In this work, a well-known efficient catalyst nanosphere Fe2O3 has been loaded on the palygorskite to improve its dispersibility. A series of Fe2O3/palygorskite (FOP) were obtained and first used for peroxymonosulfate (PMS) activation to remove bisphenol A (BPA) under visible light (Vis, λ ≥ 400 nm). The FOP-2.0 prepared with a loading ratio of 2.0 g Fe(NO3)3·9H2O per g of palygorskite exhibits excellent catalytic performance for pollutant removal. Under the optimal conditions of 0.8 g L−1 FOP-2.0, 1.0 mM PMS and neutral pH, 90.3 % of 0.05 mM BPA was removed in the presence of 300 W Xenon lamp light within 60 min reaction time. To comprehensively investigate the underlying mechanism of Vis/FOP-2.0/PMS system, chemical quenching experiment, electron paramagnetic resonance (EPR) technique, electrochemical test and X-ray photoelectron spectroscopy (XPS) analysis were conducted in FOP-2.0/PMS system with or without visible light irradiation. Surface-bound sulfate and hydroxyl radicals were revealed to be the primary reactive species in the dark system, which proliferated with the introduction of visible light, thanks to the fact that the photogenerated electrons (e−) accelerated the redox cycle of Fe(III)/Fe(II) towards PMS activation. Additionally, photogenerated holes and a very small amount of free radicals participated in BPA abatement in the Vis/FOP-2.0/PMS system. The practicability of Vis/FOP-2.0/PMS system was further validated by applying natural sunlight irradiation, treating various pollutants and investigating the interference of coexisting anions as well as the recycling use performance in water. Overall, this work sheds light on the design of green, efficient and low-cost heterogeneous photocatalysts and provides new insight into the mechanism regarding the enhancement of photocatalytic activity by visible light.

KW - Fe(III)/Fe(II) cycle

KW - Fe2O3

KW - Palygorskite

KW - Peroxymonosulfate

KW - Visible light

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85199215035&origin=inward&txGid=e975d19ba79c5adbbcc6429922b21663

UR - https://www.mendeley.com/catalogue/7d13ecbf-8c4b-3107-8bbb-dae7f76acdb1/

U2 - 10.1016/j.cej.2024.154055

DO - 10.1016/j.cej.2024.154055

M3 - Article

VL - 496

JO - Chemical Engineering Journal

JF - Chemical Engineering Journal

SN - 1385-8947

M1 - 154055

ER -