Hydroxyl Radical Research Articles

Photodegradation of ciprofloxacin and its interaction with Cu(II) in different water matrices: Insight into degradation pathways

Co-contamination of ciprofloxacin (CIP) and Cu(II) is common in marine aquaculture water. However, the transmission and transformation of these substances in natural water matrices are often overlooked. This study sought to assess the impact of Cu(II) on CIP degradation in distilled (DI) and simulated (SI) mariculture water, as well as to develop a relationship between Cu(II), CIP, and its degradation products. First, complexation assays and analog computations revealed that Cu (II) forms complexes by binding to the oxygen atoms of the carbonyl (C=O) and carboxyl (COOH) groups in the CIP molecule. Second, photodegradation experiments showed that Cu(II) significantly hindered the degradation effect of CIP in DI water, while Cu(II) did not significantly hinder the degradation of CIP in SI water. Furthermore, the effect of Cu(II) on the degradation mechanism of CIP was determined by combining quenching and EPR experiments, Materials Studio software calculations, and UPLC-MS results. It was demonstrated that Cu(II) enhanced the production of singlet oxygen (1O2), hydroxyl radicals (•OH), and superoxide radicals (•O2−) in DI water. In the presence of Cu(II), CIP undergoes hydroxylation and decarbonylation reactions, forming hydroxylated and nitroxylated products. Additionally, direct defluorination and cleavage of the piperazine ring occur, followed by complexation reactions with Cu(II). However, in SI water, the production of 1O2 depends on the indirect action of Cu(II) and the excited state transformation of organic matter. Experimental evidence has shown that CIP can create intermediate compounds that include O-O peroxide rings, with or without the presence of Cu(II). When Cu(II) is present, the cyclopropyl group of the CIP molecule is more prone to transformation and so degradation. Finally, the toxicity assessment results indicated that both Cu(II) and SI water increased the toxicity of the degradation products.

Mitigation of di-(2-ethylhexyl) phthalate contamination exposure over supramolecular organic heterojunction

Di-(2-ethylhexyl) phthalate (DEHP) with endocrine disrupting toxicity has been widely concerned owing to its widespread presence in environment and food. As an essential part of the daily diet, edible oil has become an emerging and nonnegligible source of DEHP intake exposure. Herein, we demonstrated a two-step method to mitigate DEHP exposure from edible oil including firstly selective adsorption and then photocatalytic degradation by supramolecular organic nanomaterial composites. Perylene diimide (PDI) heterojunction with Bi2WO6 was synthesized by a facile ultrasonic-water bath heating method. It was found that PDI/Bi2WO6 showed selective adsorption of DEHP in edible oil via π-π stacking, hydrophobic interactions, and monolayer chemisorption compared with other phthalates. Adsorption kinetics and isotherm simulation results showed that the adsorption process conformed to the second-order kinetics and Langmuir model. Then, under visible light irradiation, PDI/Bi2WO6 with 35 % m(PDI)/m(Bi2WO6) had the highest degradation rate of DEHP, which was 2.16 and 1.76 times higher than that of PDI and Bi2WO6, respectively. The reactive species generated under visible light irradiation, superoxide radicals (•O2−), hydroxyl radicals (•OH), and holes (h+) were synergistically involved in the photodegradation of DEHP to the intermediates of mono(2-ethylhexyl) phthalate (MEHP), mono-dibutyl phthalate (MBP), phthalic acid (PA), and 4-oxohexanoic acid. These findings may provide a technology for minimizing and treating contaminants exposure in the environment and foodstuffs through supramolecular organic nanomaterial heterojunction.

Inhalation of H2/O2 (66.7 %/33.3 %) mitigates depression-like behaviors in diabetes mellitus complicated with depression mice via suppressing inflammation and preventing hippocampal damage

Diabetes mellitus complicated with depression (DD) is a prevalent psychosomatic disorder. It is characterized by severe cognitive impairment, and associated with high rates of disability and mortality. Although conventional treatment options are available, the efficacy of these regimens in managing DD remains limited. Molecular hydrogen (H2), a selective hydroxyl radical scavenger, has shown therapeutic potential in the treatment of various systemic diseases. This study aims to investigate the therapeutic effects of H2 on DD. A DD mouse model was established through intraperitoneal injection of streptozotocin (STZ, 150 mg/kg) and lipopolysaccharide (LPS, 0.5 mg/kg). Following the induction of DD, the mice were treated with H2/O2 (66.7 %/33.3 %)inhalation for 7 days. Behavioral assessments were conducted by standard behavioral tests, and the levels of inflammatory cytokines in peripheral blood serum and hippocampal tissue were measured using enzyme-linked immunosorbent assay (ELISA). Furthermore, magnetic resonance imaging (MRI) scans and immunofluorescence staining of the hippocampus were performed to evaluate hippocampal structural integrity. The results demonstrated that inhalation of H2/O2 (66.7 %/33.3 %) significantly ameliorated depressive behaviors and symptoms in DD mice, reversed hippocampal volume reduction, decreased inflammatory cytokine levels in peripheral blood serum and hippocampal tissue, and inhibited the activation of A1 astrocytes in the hippocampus. Our study suggests that H2/O2 (66.7 %/33.3 %) inhalation therapy may offer a promising treatment strategy for DD and its associated symptoms.

Optimization of ultrasonic-assisted debittering of Ganoderma lucidum using response surface methodology, characterization, and evaluation of antioxidant activity.

Ganoderma lucidum (G. lucidum) has gained increasing attention as a potential health care product and food source. However, the bitter taste of G. lucidum has limited its development and utilization for the food industry. The response surface methodology was employed to optimize the inclusion conditions for the debittering of G. lucidum. The effects of 2-hydroxypropyl-β-cyclodextrin concentration (12-14 g/mL), ultrasound temperature (20-40°C and host-guest ratio (1:1-2:1) on response variables were studied. The physical characteristics of inclusion complexes prepared through spray drying and freeze drying were analyzed. The antioxidant activity of the different treated samples was subsequently investigated. Study results showed that, in comparison to the control group, the inclusion solution displayed a significantly enhanced taste profile under optimal processing conditions, exhibiting an 80.74% reduction in bitterness value. Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (NMR) studies indicated the successful formation of inclusion compounds. The moisture content and bulk density of spray-dried powder were found to be significantly superior to those of freeze-dried powder (p<0.05). In comparison to the diluted solution, the inclusion liquid demonstrated a 20.27%, 30.01% and 36.55% increase in ferric ion reducing antioxidant power (FRAP), hydroxyl radical scavenging and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging respectively. Further, the DPPH clearance of microencapsulated powder was not significantly different from that of tocopherol at a concentration of 25 mg/mL. In summary, the study provides theoretical basis and methodological guidance to eliminate the bitterness of G. lucidum, and therefore provide potential options to the use of G. lucidum as a food source.

Modeling Analysis of Nocturnal Nitrate Formation Pathways during Co-Occurrence of Ozone and PM2.5 Pollution in North China Plain

The rapid formation of secondary nitrate (NO3−) contributes significantly to the nocturnal increase of PM2.5 and has been shown to be a critical factor for aerosol pollution in the North China Plain (NCP) region in summer. To explore the nocturnal NO3− formation pathways and the influence of ozone (O3) on NO3− production, the WRF-CMAQ model was utilized to simulate O3 and PM2.5 co-pollution events in the NCP region. The simulation results demonstrated that heterogeneous hydrolysis of dinitrogen pentoxide (N2O5) accounts for 60% to 67% of NO3− production at night (22:00 to 05:00) and is the main source of nocturnal NO3−. O3 enhances the formation of NO3 radicals, thereby further promoting nocturnal N2O5 production. In the evening (20:00 to 21:00), O3 sustains the formation of hydroxyl (OH) radicals, resulting in the reaction between OH radicals and nitrogen dioxide (NO2), which accounts for 48% to 64% of NO3− formation. Our results suggest that effective control of O3 pollution in NCP can also reduce NO3− formation at night.

Designed magnetic nanoparticles for ferroptosis: Release of iron ions from metal-organic frameworks modified with iron oxides

The unique chemical properties of the catalytic and biocompatible metal organic framework MIL88b allow for considering it as prooxidant agent. The authors hypothesize whether additional modification of the MIL88b with an additional iron source as Fe3O4 nanoparticles can increase both pro-oxidant activity and provide magnetic properties contributing to target delivery. The prooxidant activity of the Fe3O4-MOF was studied using electron paramagnetic resonance spectroscopy and methylene blue degradation reactions in the presence of hydrogen peroxide. To understand the reaction mechanism, the authors studied the released iron ions, as well as the surface composition using the X-ray photoelectron spectroscopy method. The addition of iron oxide leads to a more prolonged release of iron ions and the production of hydroxyl radicals within 24 h. The native MIL88b demonstrates the highest Fenton reaction rate due to "sacrificial" behavior (despite lower concentration of iron ions in the composition and on the surface compared to the modified sample) and the blocking of the active centers of MIL88b by Fe3O4 on the surface.

Fluorescence sensor enabled control of contaminants of emerging concern in reclaimed wastewater using ozone-based treatment processes

Contaminants of emerging concern (CEC) pose significant challenges to environmental and human health. The development of the wastewater reuse sector, coupled with progressively stringent regulations, needs innovative systems that integrate advanced treatment processes with in-situ and real-time monitoring of CEC. This study investigates the use of a tryptophan-like fluorescence sensor for real-time and online monitoring of CEC within a pilot plant employing O3-based advanced oxidation processes (AOPs). Two tertiary wastewater effluents (WW-1 and WW-2) were tested, placing the pilot system downstream of two different wastewater treatment plants (WWTPs). Priority substances and micropollutants detected in the investigated water matrixes such as pharmaceuticals, per- and polyfluoroalkyl substances (PFAS) were selected as targeted compounds in this study. Fluorescence degradation was detected in real-time by the sensor, showing a high capability to detect fast changes in water quality induced by oxidation. Furthermore, the real-time fluorescence showed better sensitivity than lab-scale fluorescence in detecting the fast action of hydroxyl radicals (·OH) during the O3/H2O2 process, highlighting the importance of online monitoring. Selected CEC were degraded by AOPs with different percentages of removal efficiency (RE) (0%<RE<100% in WW-1 and 15%<RE<90% in WW-2) depending on oxidant doses and the reactivity of compounds with O3 and ·OH. Fluorescence data by online sensor enabled accurate prediction of the removal of a wide spectrum of CEC during O3 and O3/H2O2 processes (R2≥0.93). Furthermore, real-time fluorescence data were successfully used to predict observed pseudo-first-order rate constants of CEC with O3 or O3/H2O2. Obtained results suggest that real-time fluorescence monitoring is an excellent tool to control CEC removal during O3-based AOPs and monitor the transferred ozone in wastewater (R2≥0.94), contributing to the optimization of reagent dose, energy and costs.

Enhanced photodegradation of organic dyes using copper and zinc aluminate nanophotocatalysts

This study aims to enhance the photocatalytic efficiency of CuxZn1-xAl2O4 (x = 0.0, 0.2, 0.4, 0.6, and 0.8) nanophotocatalysts synthesized via a sol-gel self-combustion method. Rietveld analysis confirmed the formation of single-phase spinels with a face-centered cubic structure and Fd-3m space group symmetry, while electron density distribution analysis supported the ionic character of bonding within the material. Subsequent UV–visible spectroscopy revealed that the addition of Cu(II) reduced the band gap from 4.66 eV to 2.54 eV, facilitating enhanced light absorption. Consequently, the catalyst with x = 0.8 deteriorated 95 % of methyl orange (MO) and 93 % of rhodamine-B (RhB) in 120 min of visible light irradiation, following a pseudo-first-order kinetic model. The Cu0.8Zn0.2Al2O4 sample demonstrated significant reusability and stability, with degradation rates of 93–79 % for RhB and 95–81 % for MO after four cycles. Scavenging studies indicated that photoexcited holes (h), hydroxyl radicals (OH•), and superoxide radicals (O₂•⁻) were key factors in the degradation process. This study presents an improved approach for enhancing the photodegradation performance of the Cu0.8Zn0.2Al2O4 catalyst for pharmaceutical and wastewater treatment applications.

Bisulfite enhances p-nitrophenol degradation by zero-valent iron under oxic conditions: Combination of indirect reduction by superoxide radical and direct reduction

Advanced oxidation processes based on the combination of zero-valent iron (ZVI) and S(IV) have been extensively investigated for oxidative degradation of organic pollutants, but little attention has been paid to their reducing capacities in the presence of oxygen. This work found bisulfite (BS) could greatly enhance the degradation of p-nitrophenol (PNP) by ZVI under oxic conditions and PNP was only reduced to p-aminophenol without further degradation. A combination of indirect reduction by superoxide radical (O2•–) and direct reduction by ZVI was verified as the mechanism of PNP degradation. Highly oxidizing species, such as hydroxyl radical (HO•) and sulfate radical (SO4•−), were also produced in the ZVI/BS system under oxic conditions but did not contribute to pollutant degradation perhaps due to the rapid consumption by reducing substances like BS ions and the released Fe2+. BS concentration, ZVI dosage, initial solution pH and coexisting anions (CO32–, PO43– and Cl–) affected the degradation of PNP. ZVI lost the reactivity after used for three times because of the production of goethite and lepidocrocite covered on its surface. This study will provide a new insight into degradation of organic pollutants in ZVI/BS system under oxic conditions.

Heterocyclic effect boosted peroxidase-like activity of MIL(Fe) metal-organic framework for colorimetric assay and dye removal

Metal-organic frameworks (MOFs) have emerged as promising candidates for enzyme mimics due to their abundant pore structures and adjustable active sites. The catalytic activity particularly depends on the electronic character of the organic ligand. In this study, we report an iron-based MOF nanozyme FeTDC, created by replacing the 1,4-dicarboxybenzene ligand with five-membered 2,5-thiophenedicarboxylic acid (H2TDC). In comparison with the phenyl analogue, the sulfur-based heterocyclic ligand demonstrates high electron delocalization, and a low pKa value, which are beneficial for enhancing the metal/ligand interactions. Accordingly, FeTDC can facilitate the oxidation of the benzidine substrate in the presence of H2O2, thereby exhibiting remarkable peroxidase-like activity. The generation of hydroxyl radical (•OH) at the Fe active sites contributes to the catalytic process. Furthermore, the smartphone-assisted colorimetric assay of pyrophosphate was developed with high sensitivity, based on its inhibitory effect. When FeTDC was utilized for the removal of benzidine dye under high-salt condition, a 90 % of removal rate was achieved due to the synergistic effect of enzyme catalysis and physical adsorption. This work presents a novel perspective of heterocyclic effect on the design of MOF nanozymes, thereby expanding their applicability in the control of pollutants.

One-Pot Synthesis of Fe-Norepinephrine Nanoparticles for Synergetic Thermal-Enhanced Chemodynamic Therapy.

Chemodynamic therapy (CDT) is an innovative and burgeoning strategy that utilizes Fenton-Fenton-like chemistry and specific microenvironments to produce highly toxic hydroxyl radicals (•OH), with numerous methods emerging to refine this approach. Herein, we report a coordination compound, Fe-norepinephrine nanoparticles (Fe-NE NPs), via a one-pot synthesis. The Fe-NE NPs are based on ferrous ions (Fe2+) and norepinephrine, which are capable of efficient Fe2+/Fe3+ delivery. Once internalized by tumor cells, the released Fe2+/Fe3+ exerts the Fenton reaction to specifically produce toxic •OH. Moreover, the internal photothermal conversion ability of Fe-NE NPs allows us to simultaneously introduce light to trigger local heat generation and then largely improve the Fenton reaction efficiency, which enables a synergetic photothermal and chemodynamic therapy to realize satisfactory in vivo antitumor efficiency. This proof-of-concept work offers a promising approach to developing nanomaterials and refining strategies for enhanced CDT against tumors.

Atomically precise copper nanoclusters mediated Fenton-like reaction for cancer chemodynamic therapy.

We developed stable luminescent morpholine-appended copper nanoclusters CuNCs@MorMB with an ultra-small size (<3 nm) and a long emission lifetime (577 ns). They mediate a Fenton-like reaction to produce reactive hydroxyl radicals (˙OH), subsequently depleting antioxidant glutathione levels for cancer chemodynamic therapy (CDT).

8-Hydroxyquinoline Series Exerts Bactericidal Activity against Mycobacterium tuberculosis Via Copper-Mediated Toxicity.

New drugs and mechanisms of action targeting Mycobacterium tuberculosis are urgently needed to solve the global pandemic of tuberculosis. We previously demonstrated that the 8-hydroxyquinoline series has rapid bactericidal activity against M. tuberculosis. In this work, we determined that the activity of the 8HQ series is potentiated by copper ions and that the activity is dependent on copper since activity was reduced when copper was depleted from the medium. We determined that exposure to 8HQs led to an increase in intracellular copper. The increase in copper ions was specific since we saw no changes for other metal cations (zinc, iron, magnesium, manganese, or calcium). We observed the transient generation of reactive oxygen species after 8HQ exposure which disappeared by 24 h. Inhibition of growth could be partially relieved by scavenging hydroxyl radicals. We excluded the possibility that 8HQs are toxic by DNA intercalation. We screened a panel of hypomorph strains and identified sensitized strains. The pattern of sensitized strains did not suggest a specific target, but metalloenzymes, proteins with Fe-S clusters, and cell envelope biosynthetic enzymes were highlighted. These data suggest that 8HQs do not have a specific intracellular target, but act as copper ionophores, and that the mode of action is via copper-dependent toxicity.

Hybrid system for nitric oxide and hydrogen production

The device for nitric oxide inhalation therapy TIANOX has been put into use in clinical practice. It produces NO in nonequilibrium plasma of a diffusive spark discharge in the air at atmospheric pressure. There is a tendency to use a therapeutic gas mixture with high NO concentration for inhalation in the developing medical treatment methods. Nitric oxide transition into active compounds such as nitric dioxide, peroxynitrite, and nitrotyrosine can lead to oxidative stress. The use of hydrogen as an antioxidant that decreases the levels of hydroxyl radicals and peroxynitrite can protect cells from oxidative damage. Positive effect of the nitric oxide mixture and hydrogen is shown in the experiments with animals.The aim of the article is to describe development and performance the first hybrid system producing nitric oxide and hydrogen that was created in Federal State Unitary Enterprise “Russian Federal Nuclear Center – All-Russian Research Institute of Experimental Physics”. The system is based on the plasmochemical generator Tianox and the hydrogen generator, which is based on the electrolyzer with a solid polymeric electrolyte. It is fitted with H2, NO, and NO2 monitor and provides a continuous monitoring of concentrations of these gases and helps ensure safety of medical procedures by disconnecting NO and H2 generators at the moment when the gas concentrations exceed maximum levels (H2max, NOmax, NO2max).Conclusion. This hybrid system for nitrogen and hydrogen production passed the first study in human successfully. The preclinical studies also demonstrated its efficacy and safety.

Catalytic performance of FeCo2O4 spinel cobaltite for degradation of ethylparaben in a peroxymonosulfate activation process: Response surface optimization, reaction kinetics and cost estimation

The presence of cosmetics and personal care products in water resources has become an increasing concern for environment due to their toxicity and persistence in aquatic medium. Peroxymonosulfate mediated advanced oxidation methods have a great potential for the efficient removal of complex organic compounds due to the generation of highly reactive radicals with high oxidation ability. Iron cobaltite, FeCo2O4 catalyst was used as a peroxymonosulfate (PMS) activator for the degradation of ethylparaben which was selected as a model personal care product ingredient. Paraben degradation was modelled and the optimum operating parameters were determined by using Box-Behnken design. The ethylparaben degradation efficiency was calculated as 94.6 % under the optimized conditions which were determined as 0.9 g/L FeCo2O4 loading, pH 6.15, and 0.26 g/L PMS dosage. The ethylparaben degradation reaction followed second-order reaction kinetics. The activation energy was evaluated as 40.1 kJ/mol. Quenching radical tests showed that the dominant reactive species were hydroxyl radicals. Toxicity of the treated samples in terms of L. sativum growth inhibition was evaluated as 1.5 %. The total cost of the treatment including the operating and the amortization costs was calculated as 0.91 €/L.

Atmospheric Oxidation of PFAS by Hydroxyl Radical: A Density Functional Theory Study

Atmospheric Oxidation of PFAS by Hydroxyl Radical: A Density Functional Theory Study

Spontaneous Production of H2O2 at the Liquid-Ice Interface: A Potential Source of Atmospheric Oxidants.

We present experimental evidence for the spontaneous production of hydrogen peroxide (H2O2) at the liquid-ice interface during the freezing of dilute salt solutions. Specifically, sample solutions containing NaCl, NaBr, NH4Cl, and NaI at concentrations between 10-6 and 10-1 M were subjected to freezing-melting cycles and then analyzed for H2O2 content. The relationship between the production rate of H2O2 and the salt concentration follows that of the Workman-Reynolds freezing potential (WRFP) values as a function of the salt concentration. Our results suggest that H2O2 is formed at the liquid-ice interface from the self-recombination of hydroxyl radicals (OH·), produced from the oxidation of hydroxide anions due to the high electric field generated at the aqueous-ice interface under the WRFP effect. Furthermore, the involvement of O2 likely acting as an electron capturer could promote to produce more OH radicals and hydroperoxyl radicals (HO2·), thus enhancing the production of H2O2 at the liquid-ice interface. Overall, this study suggests a novel mechanism of H2O2 formation in ice via its spontaneous production at the liquid-ice interface, induced by the Workman-Reynolds effect.

Revealing OH species in situ generated on low-valence Cu sites for selective carbonyl oxidation

Catalytic oxidation through the transfer of lattice oxygen from metal oxides to reactants, namely the Mars-van Krevelen mechanism, has been widely reported. In this study, we evidence the overlooked oxidation route that features the in situ formation of surface OH species on Cu catalysts and its selective addition to the reactant carbonyl group. We observed that glucose oxidation to gluconic acid in air (21% O2) was favored on low-valence Cu sites according to X-ray spectroscopic analyses. Molecular O2 was activated in situ on Cu0/Cu+ forming localized, adsorbed hydroxyl radicals (*OH) which played the primary reactive oxygen species as confirmed by the kinetic isotope effect (KIE) study in D2O and in situ Raman experiments. Combined with DFT calculations, we proposed a mechanism of O2-to-*OH activation through the *OOH intermediate. The localized *OH exhibited higher selectivity toward glucose oxidation at C1HO to form gluconic acid (up to 91% selectivity), in comparison with free radicals in bulk environment that emerged from thermal, noncatalytic hydrogen peroxide decomposition (40% selectivity). The KIE measurements revealed a lower glucose oxidation rate in D2O than in H2O, highlighting the role of water (H2O/D2O) or its derivatives (e.g., *OH/*OD) in the rate-determining step. After proving the C1-H activation step kinetically irrelevant, we proposed the oxidation mechanism that was characterized by the rate-limiting addition of *OH to C1=O in glucose. Our findings advocate that by maneuvering the coverage and activity of surface *OH, high-performance oxidation of carbonyl compounds beyond biomass molecules can be achieved in water and air using nonprecious metal catalysts.

Construction of nickel foam-supported carbon spheres doped with copper nanoparticles for efficient nitrophenol reduction

The efficient removal of 4-nitrophenol (4-NP) from wastewater is critical due to its environmental and health hazards. This study presents the synthesis and evaluation of a novel composite membrane for this purpose. By integrating nickel foam (NiF) with carbon spheres (CS) derived from eco-friendly jackfruit seeds and copper nanoparticles (CuNPs), the catalyst membrane (NiF/CS/Cu) leverages the unique advantages of each component. The NiF provides excellent electrical conductivity and structural support, while the CS enhances stability and dispersion of CuNPs. The NiF/CS/Cu membrane exhibited high stability, efficient electron transfer, and superior catalytic activity. The catalyst achieved an outstanding 98.49 % reduction efficiency in converting 4-NP to 4-aminophenol (4-AP) within just 15 minutes, with a high rate constant of 0.201 min⁻¹. Radical scavenger experiments revealed that the reduction mechanism primarily involves electron transfer, with superoxide and hydroxyl radicals playing significant roles. The NiF/CS/Cu composite demonstrated robust performance across multiple cycles, maintaining 92.18 % efficiency, and showed stable structural integrity, as confirmed by X-ray diffraction and scanning electron microscopy analyses. This study highlights the synergistic effects of combining NiF, CS, and CuNPs, offering a practical and effective solution for 4-NP removal and contributing valuable insights into environmental remediation strategies.

Customizable Three-Dimensional Printed Zerovalent Iron: An Efficient and Reusable Fenton-like Reagent for Florfenicol Degradation.

Zerovalent iron (Fe0)-based Fenton-like technology has great potential for treating recalcitrant organic pollutants (ROPs) in wastewater. However, rapidly and precisely manufacturing Fe0-based materials with the desired geometries is challenging. Herein, novel three-dimensional printed Fe0 (3DP-Fe0) and bimetallic 3DP-Ni/Fe0 were customized by 3D printing for efficient Fenton-like degradation of florfenicol (FLO), a typical antibiotic in wastewater. 3DP-Ni/Fe0 with hydrogen peroxide (H2O2) exhibited superior reactivity toward FLO than 3DP-Fe0, generating hydroxyl radicals (·OH) and atomic hydrogen to achieve >90% dehalogenation and >70% total organic carbon removal within 10 min. The resulting degradation intermediates possessed lower antibacterial activity than FLO and did not cause resistance gene proliferation in activated sludge. The Fenton-like activity of 3DP-Ni/Fe0 was similar across different shapes but increased with increasing porosity and size. Compared with powdered Ni/Fe0, 3DP-Ni/Fe0 exhibited faster electron transfer during Fe(II)/Fe(III) cycling, which increased the utilization efficiency of dissolved Fe2+ and H2O2 for ·OH production. Moreover, 3DP-Ni/Fe0 could be reused >150 times, 5-fold more than powdered Ni/Fe0, owing to its lower metal ion release and Fe0 depletion. 3DP-Ni/Fe0 with H2O2 can also efficiently remove chemical oxygen demand from real wastewater and other ROPs (e.g., acetaminophen, carbamazepine, thiamphenicol, and tetrabromobisphenol A).