Oxygen-containing Functional Groups Research Articles

Ball-Milling-Modified Biochar with Additives Enhances Soil Cd Passivation, Increases Plant Growth and Restrains Cd Uptake by Chinese Cabbage

Biochar is a popular amendment in Cd polluted soil. However, the performance of bulk biochar is still less than satisfactory, so effective modification is very important to improve its capacity to adsorb Cd. In the present study, biochar derived from reed straw was modified by ball milling with the addition of either potassium hydroxide (KOH) alone (QK) or combined with attapulgite (QKA). Both batch experiments and pot cultivation were conducted to elucidate the adsorption mechanisms of Cd by modified biochar and their effects on Cd passivation and plant uptake in Cd polluted soil. The results showed that QK and QKA could provide higher pH values, and more oxygen-containing functional groups and minerals compared with bulk biochar (YC), promoting the complexation, ion exchange and precipitation of biochar to cadmium (Cd). The modified biochar was more inclined to multi-layer, non-ideal surface and chemical adsorption, which was an endothermic process. Compared to non-biochar addition (CK), the application of QK or QKA significantly promoted the values of pH, EC, CEC, available potassium and organic matter in soil. The addition of QK, QKA and YC decreased the availability of Cd by 22.61%, 22.32% and 14.16%, accompanied by the increase of residual Cd by 47.96%, 47.60% and 37.27%, respectively, indicating the more effective passivation of the modified biochar (QK and QKA). Compared to CK, biochar applications could significantly improve Chinese cabbage growth, and decrease Cd content in the aerial/edible part of plants by 42.97, 18.16 and 7.29%, respectively, for QK, QKA and YC. With the application of QK, Cd concentrations in the aerial/edible part of Chinese cabbage were reduced to 0.15 mg kg−1 (lower than 0.2 mg/kg, the leafy vegetables national safety standard). Generally, the performance of QK on the remediation effects and vegetable production was better than that of QKA, indicating the potential of QK for the remediation of Cd-contaminated soil and the safe production of vegetables.

Hopping-Phase Ion Bridge Enables Fast Li+ Transport in Functional Garnet-Type Solid-State Battery at Room Temperature.

Composite polymer electrolytes (CPEs) containing Li6.4La3Zr1.4Ta0.6O12 (LLZTO) is widely regarded as leading candidate for high energy density solid-state lithium-metal batteries due to its exceptional ionic conductivity and environmental stability. However, Li2CO3 and LiOH layers at LLZTO surface greatly hinder Li+ transport between LLZTO-polymer and the electrode-electrolyte interface. Herein, the surface of LLZTO is boronized to obtain functionalized LLZTO, and its conversion mechanism is clarified. By dissolving the crystal structure of cellulose to obtain hopping-phase ion bridge (HPIB), which release the Li+ transport activity of its oxygen-containing polar functional group (─OH, ─O─). Therefore, a high-throughput ion transporter (HTIT-37) with high ion transfer number (0.86) is prepared by introducing the HPIB into functionalized LLZTO and polyvinylidene fluoride interface by intermolecular hydrogen bond interaction, and it is demonstrated that the HPIB acts as a "highway" for the Li+ across this heterogeneous interface. Moreover, the HPIB is found to self-adsorb on the SEI surface, leading to fast Li+ transport kinetics at anode-CPE interface. Thus, the lifespan of Li|HTIT-37|Li is over 8000 h, and the critical current density exceeds 2.3 mA cm-2. The LiNi0.5Co0.2Mn0.3O2|Li and Li1.2Ni0.13Co0.13Mn0.54O2|Li battery remains stable with the HPIB-enhanced electrode process, proving the application potential of LLZTO-based CPE in high energy density SSLMB.

Developing an activated biochar-mineral supplement for reducing methane formation in anaerobic fermentation

Abstract The effects of biochar on methane emissions from soils are well understood. However, biochar effects on methane production from livestock have received less attention. In this study, a biochar-mineral supplement for livestock was developed by pyrolyzing a mixture of wheat straw, aluminosilicates, iron sulfate, and zinc oxide at 600 ℃. The supplement was then activated using peracetic and propionic acids, and potassium nitrate. The activated biochar-mineral supplement was characterized using analytical techniques. A high surface area, a high concentration of oxygen-containing functional groups, and a high concentration of free radicals, associated with O and Fe unpaired electrons, assisted the supplement with catalysing the oxidation of methane. Microstructural analysis of the supplement suggested the formation of organo-mineral phases, rich in C, O, Fe, Si, Al, K and Ca, indicating that the biochar reacted with mineral additives to preserve them. To assess the potential of the supplement to reduce methane produced form livestock, an in vitro batch culture incubation was conducted (n = 3) with rumen fluid sourced from Holstein–Friesian steers. The supplement was incubated at inclusion rates of 0% (control), 1.5%, 4.0% and 6.0% of dry matter (DM), with a Rhodes grass hay substrate. Compared to the control, the supplement reduced cumulative gas production by 10.1% and 12.7% and methane production by 19.03% and 29.32% after 48 h when included at 4.0% and 6.0% DM (P < 0.05), respectively, without causing any detrimental impacts on fermentation parameters. The supplement assisted with reducing the concentration of dissolved mineral nutrients, such as P and Mg, when included at 4.0% and 6.0% DM (P < 0.05). Graphical abstract

UV/Ozone-Assisted Covalent Bioconjugation on Graphene Tapes.

Compared to pristine graphene, graphene oxide (GO) has intriguing advantages for biological applications, such as high compatibility and much improved solubility in an aqueous environment. In particular, the oxygen-containing functional groups on GO enable the highly stable covalent conjugation of biomolecules, which promotes its application for developing versatile functional devices. In this work, we explored an ultraviolet/ozone (UV/O3) treatment strategy to activate graphene-tape substrates (prepared by drop-casting graphene nanoplatelets on double-sided conductive carbon tapes) to achieve excellent bioconjugation capabilities. Our Fourier transform infrared spectroscopy (FTIR), wetting, and X-ray photoelectron spectroscopy (XPS) measurements confirmed the generation of high-density oxygen-containing functional groups on graphene-carbon tape, while the conductivity and electrochemical activity are merely influenced. Upon immobilizing amino-ferrocene (Fc-NH2) onto the UV/O3-activated graphene tape via carbodiimide cross-linking, a strong pair of redox peaks (corresponding to an Fc surface density over 8.0 × 10-9 mol/cm2) was observed, indicative of its "elevated" covalent conjugation capability. More remarkably, highly efficient conjugation of glucose oxidase on UV/O3-treated graphene tape was achieved, which demonstrated excellent catalytic activity, as confirmed by chronoamperometry. These results augment the great potential of UV/O3-activated graphene tape substrates for convenient fabrication of electroactive biofunctional devices with high performance.

Research on Laser Direct Transmission Welding of Transparent Polystyrene and Polycarbonate Based on Laser Surface Modification

The conventional near-infrared laser transmission welding (LTW) process for joining dissimilar transparent polymers is limited by the need to incorporate optical absorbents, which compromises joint performance and raises biocompatibility concerns. To address these issues, this study proposed a surface modification technique using femtosecond laser ablation prior to the welding process. Experiments involved 520 nm femtosecond laser ablation of transparent polymers, followed by LTW of dissimilar transparent polymers using an 808 nm laser, with subsequent characterization and mechanical property evaluations. A maximum joint strength of 13.65 MPa was achieved. A comprehensive investigation was conducted into the physical and chemical mechanisms through which laser ablation improved the welding performance of dissimilar transparent polymers. The results demonstrated that laser ablation generated microstructures that serve as substitutes for optical absorbents while also facilitating the formation of numerous oxygen-containing functional groups. These enhancements improve miscibility and bonding performance between dissimilar polymers, enabling absorbent-free welding between ablated polycarbonate (PC) and polystyrene (PS). This work confirms both the feasibility and potential application of this process for direct LTW of dissimilar transparent polymers.

Enhanced adsorption and regulation mechanism of ball milling-modified biochar on Cd and atrazine in soil.

In order to improve the adsorption and immobilization capacity of biochar for Cd and atrazine in soil, the biochar was prepared from corn straw and modified by dry ball milling under various conditions. Compared with the pristine biochar (PB), the ball-milled biochar (BB) had a larger specific surface area and more pores, the number of oxygen-containing functional groups increased significantly, and the adsorption capacity of Cd and atrazine increased by 9.0% and 139.4%, respectively. Compared with a single pollutant, the adsorption capacity of PB and BB for Cd increased by 4.6% and 9.3%, respectively, and the adsorption capacity of atrazine increased by 97.1% and 11.5%, respectively. The increase of atrazine adsorption after modification was higher than that of Cd. In the desorption test, ball-milled modification decreased the desorption rate of Cd and atrazine, while the desorption rate of atrazine was much lower than that of Cd. Therefore, the biochar modified by ball-milled had stronger adsorption and fixation capacity for Cd and atrazine, which provides a basis for more effective remediation of soil polluted by Cd and atrazine.

Influence of complex flotation reagents on flotation effect of low-rank coal and mechanism analysis

ABSTRACT This study investigates the surface characteristics of Yongshengyuan (YSY) low-rank coal, a material known for its flotation challenges, employing a suite of analytical techniques such as Zeta potential analysis, atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction phase analysis (XRD), and X-ray photoelectron spectroscopy (XPS). The flotation performance of low-rank coal was evaluated using three distinct surfactants (sodium petroleum sulfonate, hexadecyl dimethyl ammonium bromide, methyl oleate) in conjunction with 3# oil (base oil). The experimental results demonstrate that all surfactants enhance the flotation efficiency of low-rank coal, with the combination of sodium petroleum sulfonate and methyl oleate with 3# oil proving most effective. Comprehensive analyses of AFM, Zeta potential, contact angle and wetting heat of coal sample pre and post-application of the compound reagent, reveal that the surfactant preferentially interacts with the polar hydrophilic sites on the YSY low-rank coal surface. This interaction diminishes the presence of oxygen-containing functional groups on the coal surface, increases the ratio of hydrophobic groups, enhances the coal’s hydrophobicity, and consequently bolsters the flotation efficiency of the low-rank coal.

Ce/LDHs coating modified by GO applied on AZ31 alloys corrosion protection

Layered double hydroxides (LDHs) exhibit anion exchange properties and adjustable characteristics, which make them suitable for applications in the field of anticorrosion. However, the smooth growth pattern of a single LDHs nanosheet limits its effectiveness in blocking corrosive media. Graphene oxide (GO) has a large specific surface area and numerous oxygen-containing functional groups on its surface, which can form strong interactions with polar molecules. This inhibits the migration of small ions, such as Cl−. In this work, Ce was incorporated into a micro-arc oxidation (MAO) coating on the AZ31 alloy by immersion in a cerium salt solution, and GO was incorporated using a hydrothermal solution to prepare layered double hydroxide composite coating (Ce/LDHs-G). The significance of charge transfer resistance ( Rct) mainly reflects the charge transfer process at the electrode/electrolyte interface. The Rct of Ce/LDHs-G increased by one order of magnitude compared to MAO coating. The corrosion current density ( icorr) of Ce/LDHs-G coating was 3.73 × 10−8 A cm−2, lower than that of MAO coating (1.56 × 10−6 A cm−2). Additionally, the cumulative hydrogen evolution over 336 h was lower, indicating that Ce/LDHs-G coating provides effective corrosion protection for the AZ31 alloy.

Biodegradable microplastics adsorb more Cd than conventional microplastic and biofilms enhance their adsorption.

Biodegradable polylactic acid (PLA) mulch has been developed to replace conventional polyethylene (PE) mulch in agriculture to reduce plastic pollution and the accumulation of microplastics (MPs) in soil. Cadmium (Cd) is a significant soil contaminant, and can be adsorbed by MPs. It is increasingly recognised that in the natural environment biofilms can develop on MPs and that this can affect their adsorption properties. We exposed PLA and PE mulches outdoors for 16 months. MPs were then generated from pristine and weathered mulches. Biofilms developed on the weathered plastics. Oxygen-containing functional groups were detected on the weathered, but not the pristine PE, abundance of these groups increased for the weathered PLA. After removal of the biofilm the observed increases in oxygen-containing functional groups relative to the pristine plastics remained. In adsorption experiments pristine PLA MPs had a greater maximum adsorption capacity than pristine PE MPs (106-126 vs 23.2mg/kg) despite having a lower specific surface area (0.325m2/g vs 1.82m2/g) suggesting that the greater levels of adsorption were due to MP chemistry. The weathered plastics adsorbed more Cd than the pristine plastics (e.g. maximum adsorption capacities of 153-185 and 152mg/kg for the weathered PLA and PE respectively). However, after removal of the biofilm, adsorption of Cd to the weathered MPs was no greater than for the pristine plastics. This suggests that the increased adsorption of Cd due to weathering was caused primarily by adsorption onto the biofilm.

Enhanced non-radical activation of peroxymonosulfate by g-C3N4 modulated N-doped biochar: The role of extrinsic defects and oxygen-containing functional groups

Enhanced non-radical activation of peroxymonosulfate by g-C3N4 modulated N-doped biochar: The role of extrinsic defects and oxygen-containing functional groups

Investigation of adsorption parameters of saxitoxin onto loblolly pine-derived biochar synthesized at various pyrolysis temperature.

This study highlights the use of loblolly pine derived biochar for the removal of harmful algal bloom toxin, Saxitoxin (STX), from water. Biochar samples were prepared at varying pyrolysis temperatures (400, 600 and 800°C) for 60min. As pyrolysis temperature increases, enhancement in surface porosity was observed (SBET=7.26±0.2m2/g to 408.15±6.19m2/g) while a decline in oxygen-containing functional groups was observed (1517.80±14.98μmol/g to 823.01±7.72μmol/g). This study aimed to discover the effects of adsorption parameters such as biochar dosage amount, contact time, initial concentration and initial pH on Saxitoxin adsorption. These studies revealed impressive results with >90 % toxin removal with dosage rate of 0.01g/L, contact time of 30min, and increasing percent removal with increasing initial STX concentration and initial pH in water. Maximum uptake was calculated for P400 with adsorption capacity of 314.37μg/g. This showed that surface functionality showed higher affinity for STX uptake, which may be possible due to hydrogen bonding, electrostatic interactions, ion-exchange, and π-π interactions. Applied kinetic models indicated both physisorption and chemisorption interactions with best fit supporting the Elovich models. Complementary, adsorption isotherm analysis confirmed the multilayer adsorption behavior of the Freundlich model. Therefore, these findings support the viable use of biochar material for the remediation of STX waters.

PEI-SiO2/GO Nanofiltration Membrane: Achieved high water permeability and dye rejection rate

Water pollution has long been a significant issue, and the purification of dye wastewater plays a crucial role in addressing this problem. Graphene oxide (GO) has found extensive applications in water treatment due to its unique two-dimensional (2D) structure and a surface rich in a large number of oxygen-containing functional groups. We introduced silica(SiO2) and polyethyleneimine(PEI) into GO to prepare a membrane. The experimental findings revealed that the 3-SiO2/GO binary composite membrane achieved a high water permeability of 45.6Lm-2 h-1 bar-1 while maintaining retention, which is nearly four times higher than that of the GO membrane (9.85Lm-2 h-1 bar-1).The water permeability of the PEI0.2-SiO2/GO ternary composite membrane achieved 42.37Lm-2 h-1 bar-1. The rejection rate for methyl orange dye reached 92.36%, with similar rejection rates all above 95% observed for other dyes.

A novel oxidized hierarchical porous carbon with vesicule-like ultrathin graphitic walls for efficient removal of anionic and cationic dyes.

This work developed a novel oxidized hierarchical porous carbon (OHPC) with vesicule-like ultrathin graphitic walls via a method of air oxidation and used as an efficient adsorbent for Congo red (CR) and Malachite green (MG) removal. Results show that the OHPC2 oxidized at 400°C possesses three-dimensional hierarchical pores with vesicule-like ultrathin graphitic walls. The prepared OHPC2 not only has a large specific surface area of 1020m2g-1 with a high pore volume, but also has abundant oxygen-containing functional groups. These unique structural features endow the OHPC2 with high adsorption capacities for CR (2729.5mgg-1) and MG (1697.3mgg-1) removal. The adsorption processes of CR and MG are in accordance with the Langmuir isotherm and Quasi-second-order kinetic models. The thermodynamic studies illustrate that the adsorption processes were thermodynamically feasible and spontaneous. Various characterization analysis explained that the adsorption mechanism may involve pore-filling effect, π-π conjugation, hydrogen bonding, and electrostatic attraction. Moreover, the OHPC2 exhibits good cycling stability and is identified as a desirable adsorbent for actual wastewater treatment.

Acid Pre-Treatment of Graphite Electrodes: An Alternative to Enhance the Sensing Performance of Benzenediol Isomers

Abstract Electroanalytical techniques offer several advantages, such as low cost, portability, and high analysis frequency. These benefits can be further enhanced by replacing standard electrodes (boron-doped diamond, glassy carbon, gold, platinum, etc.) with abundant, low-cost carbon materials. Pyrolytic Graphite Sheet (GS) electrodes have recently emerged as a reliable alternative, providing good stability, sensitivity, and mechanical strength. Their performance can be improved with acidic treatments. Scanning electron and atomic force microscopy images revealed irregular patterns on the edges of acid-treated GS, consistent with Raman spectra, which showed changes in the ID/IG ratio, indicating more structural defects. The acidic treatment also increased the electroactive area of GS electrodes and oxygen-containing functional groups, as observed by XPS, leading to enhanced signal currents. Additionally, electrochemical impedance spectroscopy confirmed a decrease in charge transfer resistance. Treated electrodes exhibited lower detection limits for catechol (0.58 µmol L-1) and resorcinol (0.16 µmol L-1) compared to untreated GS electrodes. The presence of potential interferents, such as KCl, NaCl, glucose, ascorbic acid, ibuprofen, paracetamol, and uric acid, did not affect the detection of catechol and resorcinol. Recovery values for spiked water samples ranged from 80% to 109%, confirming the accuracy of the proposed analytical method.

Unraveling the Trade-Off Effect of Pyrogenic Carbons Between Biopseudocapacitors and Bioconductors During Anaerobic Methanogenesis.

Pyrogenic carbons (PCs), with varying structures depending on the materials and thermal treatment conditions, have been extensively used to enhance anaerobic digestion by mediating electron transfer. However, the underlying mechanism has yet to be explored. Herein, the redirection and enhancement of the direct interspecies electron transfer (DIET) pathway were evidenced, along with the upregulated electrochemical properties and structural proteins in the methanogenic consortia. Further, we found that PCs featured trade-off properties of "biopseudocapacitor" and "bioconductor" during thermal treatment, as endowed by the evolution of oxygen-containing functional groups (for charging and discharging) and graphitic structure (for conductivity). Correspondingly, their trade-off effect on mediating syntrophic methanogenesis (SM) was realized between the generally acknowledged bioconductor role and the pseudocapacitive effect, as highlighted by the enhanced SM of reduced PCs from more balanced electron exchange capacities. Consequently, a performance comparison of PCs obtained at 450, 650, and 850 °C in SM resulted in an optimized sample at 650 °C, where a 61.3 ± 1.8% increase in methane production rate and a 33.4 ± 1.1% decrease in lag time were observed. Microbiologically, DIET-active Methanothrix and Geobacteraceae flourished with the intra- and extracellular electron transport channels established. These findings provide new insights into the mediating mechanism and renewable potential of PCs in regulating energy-harvesting biochemical processes toward carbon neutrality.

Effect of Water in Coal Matrix on the Physicochemical Adsorption Process During Low-Temperature Oxidation of Coal

ABSTRACT This study investigates the impact of water on oxygen adsorption in coal using quantum simulations, focusing on three typical oxygen-containing functional groups in lignite. Key factors, including equilibrium configurations, electrostatic potential, and reduced density gradients of water and oxygen molecules adsorbed on the coal surface, were analyzed. Thermal analysis and quantum chemical calculations were also performed to determine enthalpy changes and activation energies in oxidation reactions. The results indicate that water influences oxygen adsorption on coal surfaces through both physical and chemical mechanisms. Physically, water molecules form hydrogen bonds with the oxygen-containing groups in coal, altering the electronic density distribution and enhancing oxygen adsorption. Chemically, water reduces activation energy, modifies reaction barriers, and facilitates spontaneous combustion at lower temperatures, while also increasing enthalpy changes of oxidation reactions. Overall, water plays a dual role in regulating coal oxidation: it enhances adsorption through hydrogen bonding while also altering reaction pathways and lowering energy barriers, thereby promoting coal oxidation.

Synthesis of polyvinyl chloride modified magnetic hydrochar for effective removal of Pb(II) and bisphenol A from aqueous phase: performance and mechanism exploration

To effectively remove lead (Pb(II)) and bisphenol A (BPA) from wastewater, polyvinyl chloride modified magnetic hydrochar (PVC-AMHC) was synthesized through co-hydrothermal carbonization of polyvinyl chloride and corn straw, and subsequently activated using NaOH. Characterization demonstrated that both PVC and NaOH activation increased the content of oxygen-containing functional groups, and Fe3O4 was successfully loaded onto the material surface. Furthermore, PVC-AMHC displayed remarkable uptake capacity with the maximum uptake amount of Pb(II) (217.53 mg/g) and BPA (185.53 mg/g) at 130 and 30 min, respectively, under a wide pH range. Additionally, PVC-AMHC possessed high tolerance to different interference cations and maintained excellent adsorption performance during four regeneration cycles. The thermodynamic analysis suggested that the absorption processes of Pb(II) and BPA by PVC-MHC were spontaneous (-ΔG0) with an endothermic characteristic (+ΔH0). Adsorption mechanisms of Pb(II) on PVC-AMHC included complexation, electrostatic attraction, and pore filling, and those of BPA were mainly associated with hydrogen bonding and pore filling. In conclusion, PVC-AMHC was an environmentally friendly adsorbent with effectively simultaneous removal of Pb(II) and BPA from wastewater.Graphical

Constructing Accessible Closed Nanopores in Coal-Derived Hard Carbon for Sodium-Ion Batteries.

Hard carbon (HC) materials are suitable anodes for sodium-ion batteries (SIBs) but still suffer from insufficient initial Coulombic efficiency (ICE). Promoting sodium storage via the pore filling mechanism is an effective way to improve the ICE, and the key here is regulating the pore structures of HC. In this work, coal-derived HC is successfully engineered with abundant accessible closed nanopores by treating the coal precursors with a facile destructive oxidation strategy. Investigations demonstrate that the destructive oxidation strategy can not only introduce abundant oxygen-containing functional groups (OFGs) but also decrease the size of graphitic microcrystals. Thus, the OFGs significantly enhance the crosslinking of small graphitic microcrystals and stimulate the formation of accessible closed nanopores during carbonization, which eventually improves the ICE by promoting the pore filling mechanism. The optimized HC exhibits so far the highest ICE (92.2%) among coal-derived SIB anode materials, together with a considerable capacity of 328.5 mAh g-1 at 90mA g-1 and a capacity retention of 95.1% after 150 cycles. The results provide guidelines for developing high-performance HC materials toward the large-scale application of SIBs, which is of great significance for future energy storage systems.

Dynamic-Wetting Liquid Metal Thin Layer Induced via Surface Oxygen-Containing Functional Groups.

Enhancing the wettability of liquid metals (LMs) to address their high surface tensions is crucial for practical applications. However, controlling LMs wetting on various substrates and understanding the underlying mechanisms are challenging. Here, we present a facile dynamic-wetting strategy to modulate eutectic gallium-indium (EGaIn) wettability via chemical surface modification, spontaneously forming a stable and thin (∼18 μm) EGaIn layer. Polymer substrates exhibiting varying EGaIn wetting behaviors can be categorized by their sliding angles and adhesion force. X-ray photoelectron spectroscopy results demonstrate that the dynamic-wetting process occurs only on surfaces with sufficient oxygen-containing functional groups (content ≥18%) and confirm coordination interactions between the EGaIn oxide layer and surface functional groups. Furthermore, in EGaIn thermal management systems, the heat transfer rate in the wetting group is increased by up to 20% compared to that of the nonwetting group. This work will hasten the application of LMs in flexible circuits and thermal management.

Polylactic acid microplastics before and after aging induced neurotoxicity in zebrafish by disrupting the microbiota-gut-brain axis.

Polylactic acid (PLA) is a biodegradable alternative to traditional plastics due to its excellent biocompatibility. However, PLA is challenging to fully degrade and can easily become microplastics (MPs) in surface water, a process accompanied by aging. This study found that aged PLA (APLA) MPs exhibited increased surface roughness, decreased surface potential, and more oxygen-containing functional groups compared to PLA. Acute exposure to PLA/APLA in zebrafish larvae resulted in sluggish behavior and inhibited neuronal development. Chronic exposure to PLA/APLA in adult zebrafish led to reduced exploratory behavior, poor memory, increased aggression, and neuron loss. Overall, PLA/APLA induced dose-dependent neurotoxicity, with APLA exhibiting greater toxicity than PLA, potentially due to its higher rate of uptake. Additionally, exposure to PLA/APLA led to thinning of the intestinal wall, shortening of villi, and suppression of intestinal neurotransmitter levels, accompanied by alterations in microbial abundance and gut dysbiosis. Meanwhile, supplementation with bile acid, considered as the key regulator in the gut-brain axis, significantly mitigated the neurotoxicity induced by PLA/APLA. These findings confirm that PLA/APLA MPs indeed elicit neurotoxicity via the gut-brain axis and provide scientific evidence for targeted environmental interventions to minimize the adverse ecological impacts of biodegradable MPs.