Degradation Of Acetaminophen Research Articles

Simultaneous degradation of pharmaceuticals and personal care products in hospital wastewater using ozone under ultraviolet irradiation

The discharge of Pharmaceuticals and personal care products (PPCPs) from industries and hospitals are responsible for the contamination of water body with slow or non-degradable toxic compounds. The removal of these contaminants required advanced treatment process because of unable to treat by conventional wastewater treatment process. In this study, the degradation of PPCP compounds, including caffeine (CAF), atenolol (ATL), carbamazepine (CBZ), sulfamethoxazole (SMX), trimethoprim (TMP), and acetaminophen (ACT) was evaluated under exposure to 1.0 and 1.5 mg/L dissolved ozone (O3), both with and without ultraviolet (UV) irradiation (254 nm). Using liquid chromatography with tandem mass spectrometry, we determined that the removal efficiency for the targeted contaminants exceeded 95 % within just 20 min of exposure to both 1.0 and 1.5 mg/L O3. However, when treated with UV light alone, the removal efficiency was limited at 3 %–11 %. A combination treatment involving dissolved 1.5 mg/L O3 and UV light led to over 97 % removal within 7 min. This outcome was attributed to hydroxylation reactions, aromatic ring opening, oxidation, and mineralization facilitated by the HO and peroxide generated through the photolysis of O3. The degradation rate of PPCP compounds followed pseudo-first-order kinetics and showed a decrease in the presence of humic acid and hospital wastewater further decreased it. Moreover, O3/UV treatment generated lower-weight degradation products. The toxicity analysis revealed that these transformation products exhibited environmental benignity and minimal health risks which O3/UV treatment potentially minimizes the presence of harmful byproducts. These findings provide a foundation for developing combined hybrid systems for PPCP containing wastewater, containing membrane filtration with ozonation system.

Porous biochar supported PET plastic waste MOF heterostructure as a novel, efficient and recyclable catalyst for acetaminophen degradation

Herein, the innovative hybrid photocatalyst PET-based Zn-MOF on orange peel biochar (BC)(PZM/BC) was designed and synthesized via the hydrothermal method. Electrochemical methods have been used to demonstrate the action of the PET-MOF in the PZM/BC photocatalyst as a medium for electron transfer. The latter involved the synthesis of a zinc-containing metal–organic framework (MOF) in which the linkers were derived from the depolymerization of polyethylene terephthalate (PET) originating from plastic wastes. According to research, the catalytic reactions are sped up when porous BC and linker PET are assimilated into PZM/BC photocatalyst hetero-junction. Furthermore, BC stored electrons under light and released these electrons under dark conditions. When BC was combined with PET-MOF, the electrons on the biochar activated the catalytic redox activity of acetaminophen. Additionally, it lowers the reassimilation rate due to the combined meshed nanostructures and functionality of PET-MOF and PZM/BC. UV–Vis DRS, Mott-Schottky, Photoluminescence(PL), and Electrochemical Impedance spectra(EIS) results showed that the PZM/BC exhibited efficient spatial separation and transportation of photogenerated charge carriers and exhibited superior photocatalytic ability. Electron spin resonance(ESR) analysis confirmed that ⋅OH and h+ were the predominant radical species responsible for the degradation of acetaminophen(ACT). The optimum conditions for ACT removal were observed at pH 6.07, with a PZM/BC dosage of 0.1 g L−1, and an initial ACT concentration of 50 mg L−1, highlighting the pivotal role of the PZM/BC system in ACT degradation. Furthermore, potential photocatalytic degradation pathways of ACT were inferred renders on the identified intermediates which are responsible for the degradation of refractory intermediates. Regeneration trials were carried out to assess the stability of the photocatalyst. Additionally, the degraded intermediates generated during the degradation processes were examined, providing a comprehensive elucidation of the degradation mechanism.Graphical

Degradation of methylene blue and acetaminophen with Fe-TiO2 nanoparticles catalyzed by UV/visible light and sunlight

Degradation of methylene blue and acetaminophen with Fe-TiO2 nanoparticles catalyzed by UV/visible light and sunlight

Photocatalytic degradation of acetaminophen, ciprofloxacin and amoxicillin using UV/ZnO in a suspended photocatalytic reactor

Abstract This study aims at evaluation of the photocatalytic degradation of pharmaceutical compounds acetaminophen (ATM), ciprofloxacin (CXN), and amoxicillin (AMX) using zinc oxide (ZnO) nano powder as a photocatalyst in a suspended reactor using a 16 W UV lamp. Operating parameters pH, catalyst dosage, and pollutant concentration were optimised for a working volume of 1.3 litres of model pharmaceutical compounds. The photo degradation efficiency was 95% at pH 6 after 5 h of irradiation for ATM, 98% at pH 6 after 2 h of irradiation for CXN, and 100% at pH 10 after 3 h of irradiation for AMX. The reaction kinetics for the degradation of ATM, CXN, and AMX followed pseudo-first order with the rate constants in the order of kAMX>kCXN>kATM 0.0321 min−1, 0.0232 min−1 and 0.0070 min−1 respectively. TOC (Total Organic Carbon) analysis was carried out for the model compounds, among which compound amoxicillin was found having a higher rate constant of about 0.0108 min−1, which is 1.2 times higher than ciprofloxacin and 2.5 times greater than acetaminophen. This study concludes that ZnO nano powder is efficient in degrading the model pharmaceutical compounds ATM, CXN, and AMX by utilising the UV light, which is evident from the results of the UV–vis spectrophotometer, HPLC analysis, and mineralisation study. In addition, ANOVA was performed on the results obtained from optimisation studies, which confirms the substantial influence of the operating parameters on the degradation of the compounds.

Photocatalytic Degradation of Acetaminophen Using Carbon-TiO2 Nanocatalyst Extracted from Hibiscus Flower under Visible Light

In today’s world pharmaceutical waste in the Environment has become a worldwide issue. These compounds are used in living beings to cure diseases and prevent them. But the disposal of these types of waste was not disposed of properly. In this study, the pharmaceutical compound – “Acetaminophen” (ACT) was degraded using photocatalytic degradation which is one among the pharmaceutical waste. The Compound is much harmful to living beings and causes severe disorders like vomiting and nausea. In this paper, the Acetaminophen is degraded using the carbon-TiO2 nanocatalyst. The Carbon-TiO2 nanocatalyst was synthesized and characterized such as particle size, zeta potential, FTIR, Surface area analyzer, EDX, and SEM images. The Acetaminophen was degraded by using Photocatalytic degradation under transparent condition. The analysis of disintegration was performed by using the UV-vis spectrophotometer. The results obtained indicated the maximum degradation efficiency of around 87% obtained. Hence, C-TiO2 can be utilized under visible light to effectively degrade Acetaminophen.

Recognizing the relevance of non-radical peroxymonosulfate activation by co-doped Fe metal-organic framework for the high-efficient degradation of acetaminophen: Role of singlet oxygen and the enhancement of redox cycle

A bimetallic MOF derivative consisting of Fe and Co (Fe/Co2-MOF) by Co-doping MIL-101(Fe) was successfully synthesized for peroxymonosulfate (PMS) activation in acetaminophen (N-Acetyl-Para-Amino-Phenol, APAP) degradation. The presence of Co significantly accelerated the transfer of electrons due to the synergistic effect between Fe and Co bimetallic sites. Specifically, the reaction rate constant of APAP in the Fe/Co2-MOF + PMS system was three orders of magnitude higher than that of MIL-101(Fe) alone and 90 times higher than that of the MIL-101(Fe) + PMS system, respectively. At room temperature, 100 % of the APAP was degraded in 15 min with a Fe/Co2-MOF concentration of 0.05 g/L and a PMS concentration of 0.8 mmol/L across a wide pH range from 3 to 9. High-valence metal species (CoIV and FeIV) and electron transfer-dominated nonradical processes were responsible for the APAP degradation. Although singlet oxygen (1O2) was identified as the main active species in our study, the relative contribution of 1O2 was negligible. The catalytic performance was particularly notable in the practical implementation of hospital sewage treatment. However, it is still urgent to seek ways to relieve cobalt leaching of Fe/Co2-MOF. This strategy of Co-doping provides a clear illustration of modulating MIL-101(Fe) ultimately maximize their catalytic efficiency in PMS activation for water purification.

Preparation of iron selenide decorated 1T/2H molybdenum disulfide catalysts for peroxymonosulfate activation: Effect of phase transition

The sulfate radical-based advanced oxidation process is recognized as an effective approach for acetaminophen (ACT) degradation. Modification of MoS2 through phase engineering can contribute to enhancing peroxymonosulfate (PMS) activation performance. In this work, we decorated MoS2 with FeSe2, aiming to alter the 1T/2H phase ratio of MoS2. Experiments and calculations suggested that the incorporation of FeSe2 increases the activation pathway through the Fe(III)/Fe(II) cycle and prompts a phase transition from 2H to 1T, providing active sites and boosting charge transfer between FeSe2 and MoS2. The optimum catalyst (FeSe2@MoS2-10) showed high efficiency in PMS activation, achieving complete removal of ACT within 20 min. The pseudo-first-order rate constant (kapp) on this catalyst is 17.7 times higher than that of the MoS2/PMS system. This study provides a new direction for promoting phase transition and improving the catalytic reactivity of MoS2-based catalysts, expanding their potential applications in pharmaceutical wastewater treatment.

Performance and reaction mechanism of montmorillonite/α-Fe2O3/starch bio-nanocomposite as high-efficiency photocatalytic degradation of acetaminophen: Characterization, feasibility, and pathway

The worldwide challenge of eliminating pharmaceutical contaminants requires immediate attention. Developing bio-based catalysts that are eco-friendly, reusable, and high-performance, employing starch (ST) and montmorillonite (MMT) as support, holds tremendous promise as a novel biocatalyst for pharmaceutical waste removal. In this study, a montmorillonite/α-Fe2O3/starch (MMT/α-Fe2O3/ST) bio-nanocomposite photocatalyst was successfully synthesized and used for acetaminophen (ACT) degradation under UVA-LED irradiation. The influence of operational factors, such as catalyst, ACT concentrations, and solution pH, on photocatalytic activity was examined in detail; catalyst: 0.75 g/L, pH: 7.1, leading to total ACT (10 mg/L) removal in ∼80 min. MMT/α-Fe2O3/ST showed excellent durability due to negligible Fe leaching. After four successive degradation cycles, ACT and TOC elimination efficiencies remained over 91 and 42.7 %. Compared to other anions studied, carbonate ions suppressed the most ACT degradation. Based on the radical scavenger experiments, hydroxyl and superoxide radicals and holes were involved in the MMT/α-Fe2O3/ST system. LC-MS results were used to propose ACT degradation pathways. This work illuminated the significance of biocatalysts in removing emerging pollutants from wastewater.

Charge transport properties and photostability of microcrystalline cellulose derived from Gigantochloa scortechinii-supported ZnO for enhanced acetaminophen degradation

A facile chemical mixing procedure was utilized to fabricate microcrystalline cellulose (MCC) derived from Gigantochloa scortechinii-supported ZnO photocatalysts, with different MCC content. The successful incorporation of ZnO onto the MCC surfaces was characterized by multitudinous characterization techniques. The photocatalytic evaluation studies were carried out under a very low UVC light intensity (9 W) against acetaminophen (ACE) in the aqueous solution. The MCC-supported ZnO (0.5:1) composites photocatalyst demonstrated a rapid and enhanced performance within 180 min under normal conditions, with a two-time higher value of rate constant k (1.12 ×10−2 min−1) as compared to pristine ZnO. The improved efficiency under UVC irradiation was associated with the excellent separation capability of photoexcited charge carriers, ease of electron migration, and electrons’ mediators by the MCC in the composite photocatalyst, as demonstrated by the band gap and photoluminescence analyses. The major reactive species were found to be hydroxyl radicals (•OH) and photoexcited holes (h+). The best photocatalyst has high photostability since it can be recycled up to five times towards ACE degradation without any regeneration step.

MOF-derived hollow Co@N-doped carbon as an efficient peroxymonosulfate activator for acetaminophen degradation: Dominant sulfate radical-induced degradation pathway

Carbonaceous materials have been proven as promising peroxymonosulfate (PMS) activators to eliminate recalcitrant organic contaminants in wastewater. Herein, in this study, we proposed to fabricate hollow-structured cobalt (Co)-embedded in nitrogen-doped carbon (H-Co@SNC) derived from a star-like bimetallic ZnCoMOF (S-ZnCoMOF) through two-step modifications. This as-prepared H-Co@SNC exhibited a hollow configuration with peculiar physicochemical properties verified by different characterizations (XRD, BET, Raman, TGA, XPS, etc) that would be contributed to its excellent catalytic activity in PMS activation to degrade a residual pharmaceutical contaminant, acetaminophen (ACE) in water. Based on the experimental results, H-Co@SNC/PMS system can completely degrade ACE in 10 min with a high total organic carbon (TOC) removal content of 76.5 % compared with other tested systems. On the other hand, quenching experiments and electron paramagnetic resonance (EPR) analysis were employed to explore the generation of various reactive species, high-valent cobalt-oxo, and electron transfer involved in ACE degradation, in which SO4●− played a pivotal role. The intermediate products and plausible degradation pathways of ACE were proposed whereas the toxicity of the intermediates was also assessed. This work provides an insight into the preparation strategy for synthesizing a hollow-structured metal-doped carbon material that would be a promising PMS activator for eliminating organic pollutants in wastewater.

Mechanistic Investigation of Rapid Catalytic Degradation of Acetaminophen Using Electrochemical-Induced CoFe2O4 by Activation of Peroxymonosulfate

Advanced oxidation technology based on PeroxyMonoSulfate (PMS) has become a research hotspot in the field of water treatment. To improve the activation efficiency of PMS, electrochemically assisted spinel type catalyst CoFe2O4 was used to activate PMS and achieve effective degradation of acetaminophen. The influence of single factor on degradation was explored to determine the best degradation process parameters of E/CoFe2O4/PMS system. Results show that under the optimum reaction conditions (DC voltage is 6[Formula: see text]V, the initial mass concentration of acetaminophen is 10[Formula: see text]mg[Formula: see text]L[Formula: see text], the dosage of CoFe2O4 is 0.3[Formula: see text]g[Formula: see text]L[Formula: see text], and the mass concentration of PMS is 1.5[Formula: see text]g[Formula: see text]L[Formula: see text]), the degradation rate of acetaminophen reaches up to 95% within 20[Formula: see text]min. CoFe2O4 catalyst showed a good stability, with only a 12% decrease in acetaminophen degradation after three cycles. Radical quenching tests show that [Formula: see text] and [Formula: see text] played predominant roles in the advanced oxidation process. This work provides a new strategy for more efficiency in PMS activation.

Synthesis and photodegradation performance of a heterostructure ferromagnetic photocatalyst based on MWCNTs functionalized with (3-glycidyloxypropyl)trimethoxysilane and decorated with tungsten trioxide for metronidazole and acetaminophen degradation in aqueous environments.

The presence of metronidazole (MNZ) and acetaminophen (ACE) in aquatic environments has raised growing concerns regarding their potential impact on human health. Incorporating various patterns into a photocatalytic material is considered a critical approach to achieving enhanced photocatalytic efficiency in the photocatalysis process. In this study, WO3 nanoparticles, which were immobilized onto ferromagnetic multi-walled carbon nanotubes that were functionalized using (3-glycidyloxypropyl)trimethoxysilane (FMMWCNTs@GLYMO@WO3), exhibited remarkable efficiency in removing MNZ and ACE (93% and 97%) in only 15 min. In addition, the new visible-light FMMWCNTs@GLYMO@WO3 nanoparticles as a magnetically separable photocatalyst were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), EDS-mapping, vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), diffuse reflectance spectroscopy (DRS), high-performance liquid chromatography (HPLC), and total organic carbon (TOC) due to detailed studies (morphological, structural, magnetic and optical properties) of the photocatalyst. In-depth spectroscopic and microscopic characterization of the newly developed ferromagnetic FMMWCNTs@GLYMO@WO₃ (III) photocatalyst revealed a spherical morphology, with nanoparticle diameters averaging between 23 and 39 nm. Compared to conventional multiwall carbon nanotube and WO₃ photocatalysts, FMMWCNTs@GLYMO@WO₃ (III) demonstrated superior photocatalytic activity. Remarkably, it exhibited excellent reusability, maintaining its efficiency over a minimum of five cycles in the degradation of metronidazole (MNZ) and acetaminophen (ACE).

Activation of peroxymonosulfate under visible-light illumination for enhanced degradation of acetaminophen by self-assembly iron phosphorus/hexagonal tubular graphite carbon nitride

Improving the visible light response by sulfate-based advanced oxidation processes (S-AOPs) is a promising method for the efficient degradation of organic matter in water. Herein, we facilely fabricated the iron phosphorus/hexagonal tubular graphite carbon nitride (FeP/HTCN) composites via two-phase hydrothermal supramolecular self-assembly and thermal-condensation method. FeP/HTCN with the shape of hollow hexagonal tubular loaded iron phosphorus particles was first synthesized. The results suggested that the loading of iron phosphate greatly enhanced its ability to activate peroxymonosulfate (PMS) while also improving the photocatalytic ability of the catalyst due to its smaller bandgap. The combined effect of iron phosphate, HTCN, and visible light (wavelength ≥ 420 nm) assistance facilitated the enhancement of the reaction activity. Electron paramagnetic resonance techniques (EPR) and radial quenching experiments validated that singlet oxygen (1O2) derived from superoxide was the main active species. The degradation pathways of acetaminophen (APAP) were determined and the mechanism of mineralization and decomposition was demonstrated. This work provided a proposal for the application of iron salts represented by iron phosphate in S-AOPs.

Kinetic modeling of the photocatalytic degradation of acetaminophen and its main transformation products

In this study, a kinetic model of the heterogeneous photocatalytic degradation of acetaminophen and its main transformation products is presented. Kinetic photocatalytic modeling and photon absorption rate modeling were included. Monte Carlo method was used to model the photon absorption process. Experiments were carried out in a reactor operated in batch mode and TiO2 nanotubes were used as photocatalyst irradiated with 254 nm UVC. Kinetic parameters were estimated from the experiments data by applying a non-linear regression procedure. Intrinsic expressions to the kinetics of acetaminophen degradation and its main transformation products were derived. Model, kinetics and photon absorption formulations and parameters proved to be affordable for describing the photocatalytic degradation of acetaminophen, but improvements should be done for better description of formation and oxidation kinetics of main transformation products. The model should be tested with other pharmaceuticals and emergent pollutants to calibrate it and evaluate its applicability in a wide range of compounds.

Unravelling the impact of lower vacuum activation temperature on Fe2+/Fe3+ mixed-valence unsaturated iron centres in MIL-101(Fe) and its impact on Fenton degradation of acetaminophen

The impact of varying activation temperatures under vacuum on the Metal-Organic Framework (MOF), MIL-101(Fe), and its consequential effects on H2O2 activation and Fenton degradation of one of the contaminants of emerging concerns, acetaminophen (ACT) is investigated in this work. MIL-101(Fe) underwent vacuum activation at temperatures ranging from 60 ℃ to 150 ℃, and an in-depth analysis of the resulting samples' physical and chemical properties were conducted. XRD, FTIR and microscopic studies revealed that the structure and crystallinity of the samples were preserved irrespective of the activation temperature. MIL-101(Fe) activated at 120 ℃ (MIL-101–120) demonstrated the highest degradation kinetics when examined for Fenton degradation of ACT. XPS analysis revealed that MIL-101–120 exhibited the highest Fe2+: Fe3+ ratio and a complete degradation of ACT was attained within 60 minutes of the reaction. This indicated a direct correlation between increased Fe2+ content and the rate of Fenton degradation. A possible catalytic mechanism for the ACT degradation by MIL-101(Fe) was further proposed, indicating the influence of different active sites and radicals in the reaction. Overall, the study provides insight into the significance of optimizing various activation conditions to improve the catalytic efficiency of MIL-101(Fe).

Electrochemical degradation of acetaminophen in urine matrices: Unraveling complexity and implications for realistic treatment strategies

Urine has an intricate composition with high concentrations of organic compounds like urea, creatinine, and uric acid. Urine poses a formidable challenge for advanced effluent treatment processes following urine diversion strategies. Urine matrix complexity is heightened when dealing with pharmaceutical residues like acetaminophen (ACT) and metabolized pharmaceuticals. This work explores ACT degradation in synthetic, fresh real, and hydrolyzed real urines using electrochemical oxidation with a dimensional stable anode (DSA). Analyzing drug concentration (2.5 - 40 mg L−1) over 180 min at various current densities in fresh synthetic effluent revealed a noteworthy 75% removal at 48 mA cm−2. ACT degradation kinetics and that of the other organic components followed a pseudo-first-order reaction. Uric acid degradation competed with ACT degradation, whereas urea and creatinine possessed higher oxidation resistance. Fresh real urine presented the most challenging scenario for the electrochemical process. Whereas, hydrolyzed real urine achieved higher ACT removal than fresh synthetic urine. Carboxylic acids like acetic, tartaric, maleic, and oxalic were detected as main by-products. Inorganic ionic species nitrate, nitrite, and ammonium ions were released to the medium from N-containing organic compounds. These findings underscore the importance of considering urine composition complexities and provide significant advancements in strategies for efficiently addressing trace pharmaceutical contamination.

Mn-Cu co-doped graphitic carbon nitride accelerates permonosulfate to generate more singlet oxygen in pollutant degradation

Graphitic carbon nitride (g-C3N4), a nitrogen-rich polymeric semiconductor, has gained significant attention as a photocatalyst. However, its potential to activate permonosulfate (PMS) has been somewhat limited. Prior research has demonstrated that manganese-doped g-C3N4 can effectively activate PMS to degrade pollutants, with Mn3+ playing a pivotal role. Consequently, enhancing the Mn3+ content within the system is of paramount importance. In this study, we developed a novel class of manganese‑copper doped g-C3N4 materials using a hydrothermal-calcination process. The optimized material, denoted as Mn5Cu5-CN, was synthesized at a Mn/Cu molar ratio of 1:1. When applied to degrade a model contaminant, acetaminophen (ACP), the Mn5Cu5-CN/PMS system demonstrated remarkable efficiency, degrading nearly 20 mg/L of ACP within 30 min (material dosage = 0.4 g/L, PMS concentration = 2.0 mM). The Mn5Cu5-CN exhibited favourable performance across a broad pH range. Singlet oxygen (1O2) was identified as a major player in the degradation of ACP. X-ray photoelectron spectroscopy (XPS) analyses revealed that the cyclic redox reactions of Mn3+/Mn4+ and Cu+/Cu2+ led to the abundant generation of 1O2. Superoxide (O2•-) was identified as an important intermediate product in these processes. Additionally, the g-C3N4 present in the material also facilitated the generation of reactive oxygen species (ROS). This study provides a fresh perspective on the utilization of g-C3N4 for pollutant degradation, highlighting the potential of MnCu doped g-C3N4 materials in environmental remediation.

Synthesis of TiO2 nanoplate decorated by Co particles immobilized on porous Polycalix[4]resorcinarene for enhancing photocatalytic degradation of drug acetaminophen by light Emitting Diode

The sustainability and feasibility of using visible irradiation in photocatalysis is a promising approach for water purification. In this study, photocatalytic degradation of a widely used analgesic and antipyretic drug, acetaminophen (ACM), with metal-loaded an efficient photocatalyst (TiO2NPs-Co/Polycalix (Christen et al., 2010) [4]resorcinarene (TCP)) was inv estigated using visible light. photocatalyst structural, surface, and morphological features were characterized using FTIR, XRD, TEM, EDX, PL, and DRS analyses. Considering various sites of Polycalix (Christen et al., 2010) [4]resorcinarene in the TCP, studied by trapping experiments. A novel charge transfer bridge for electron-hole recombination is made possible by using Co and TiO2 as electron transfer mediators with electronic conductivity. This results in efficient process and energy optimization, which makes it easier for ACM to degrade throughout the absorption process. The ACM (15 and 40 mg/L) achieved complete degradation under visible light irradiation with 0.6 g/L of TCP at pH = 5.0 during 120 min reaction because of the good synergetic effect of the catalyst systems. Additionally, the intermediates generated by photo electrocatalytic activities were identified, and two potential paths for degradation were suggested. Some of these organic products were identified by High-Performance Liquid Chromatography (HPLC).

Solar photocatalytic degradation of acetaminophen with TiO2 P25 immobilized on a glass plate by heat attachment method

Solar photocatalytic degradation of acetaminophen with TiO2 P25 immobilized on a glass plate by heat attachment method

Enhanced Photodegradation of Acetaminophen Using Efficient ZnO-NiO Nanofibers

The increasing presence of pharmaceutical pollutants, such as acetaminophen, in water bodies poses a significant environmental challenge due to their persistence and potential toxicity. This study investigated the enhanced photodegradation of acetaminophen using ZnO-NiO nanofibers as superior photocatalysts. The nanofibers synthesized with varying NiO contents (designated as ZN0.5, ZN1, ZN1.5, and ZN2), were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman, FTIR, Brunauer–Emmett–Teller (BET) analysis, and diffuse reflectance spectroscopy (DRS) to elucidate their structural, morphological, and optical properties. Thermogravimetric analysis (TGA) indicated that the nanofibers exhibit high thermal stability, with major weight loss attributed to the decomposition of the polymer matrix and residual organics. The BET analysis revealed that the specific surface area remains stable after increasing the NiO content up to a certain ratio. This stability correlates with the enhanced photocatalytic performance due to increased light absorption and improved charge separation. The diffuse reflectance spectra and Kubelka–Munk plots demonstrated a reduction in bandgap energy with higher NiO content, facilitating greater visible light absorption. Photocatalytic experiments under visible light irradiation, in the presence of peroxymonosulfate (PMS), showed that the ZN1.5 nanofibers achieved the highest acetaminophen degradation rate, i.e., 92%, within 3 h. Mechanistic studies, supported by radical trapping experiments, revealed that the improved photocatalytic efficiency is due to the synergistic effects of ZnO and NiO heterojunctions, which enhance charge separation and reactive oxygen species (ROS) generation. This research highlights the potential of ZnO-NiO nanofibers as effective photocatalysts for the degradation of pharmaceutical pollutants. The findings demonstrate that optimizing the composition and structure of nanofibers can significantly improve their environmental remediation capabilities, providing a promising solution for sustainable water treatment.