Construction of a stable S-scheme NiSnO3/g-C3N4 heterojunction on activated carbon fibre for the degradation of glyphosate in water under flow condition.

Creating light-harvesting heterojunctions as a photocatalyst is critical for efficiently treating organics-laden wastewater. Yet the materials stabilization and limited reusability hinder their practical applications. In this study, an S-scheme heterojunction in the Sn-based perovskite and g-C3N4 (gCN) composite, supported on an activated carbon fiber (ACF) substrate, is developed for glyphosate (GLP) degradation under water under flow conditions. The reusable NiSnO3-gCN/ACF photocatalyst was synthesized using a simple wet impregnation and calcination method. The supported photocatalyst achieved 99% GLP-removal at 4 mL/min water flowrate and 1.25 g/m2 of photocatalyst loading in ACF. The photocatalyst showed a stable structure and repeat photocatalytic performance across 5 cycles despite prolonged visible light exposure under flow conditions. The materials stability is attributed to the effective dispersion of NiSnO3-gC3N4 in ACF, preventing the photocatalyst from elution in water flow. Radical trapping experiment revealed the superoxide and hydroxyl radicals as the primary reactive species in the GLP-degradation pathway. A plausible S-scheme mechanism was proposed for heterojunction formation, based on the high resolution deconvoluted spectra of X-ray photoelectron spectroscopy and the radical trapping experimental results. The inexpensive Sn-based perovskite synthesized in this study is indicated as an alternative to Ti-based perovskites for wastewater remediation application.

Photocatalytic oxidation of glyphosate and reduction of Cr(VI) in water over ACF-supported CoNiWO4-gCN composite under batch and flow conditions.

Photocatalytic treatment of wastewater using nanomaterials is an efficient energy saving technology. Yet the practical application of the technology is limited because of difficulty in developing the stable, supported photocatalytic nanoparticles that can be used under continuous flow conditions. Here, we report an efficient removal of glyphosate (GLP) and Cr(VI) from water under batch as well as continuous flow conditions using the activated carbon fiber (ACF)-supported nanocomposite of CoNiWO4 (CNW) and g-C3N4 (gCN), as a photocatalyst. CNW-gCN/ACF is synthesized using a one-step strategy, and spectroscopic characterization techniques are used to corroborate the formation of the Z-scheme-based CNW-gCN heterojunction in the ACF substrate. Efficacy of the photocatalyst is assessed in visible light irradiation. The batch activity data of the individual pollutant show the complete oxidation of GLP at 30 ppm and reduction of Cr(VI) at 200 ppm concentration levels in 60 and 150 min, respectively at 1 g/L dose of CNW-gCN/ACF. Photocatalytic efficiency of CNW-gCN/ACF in the simultaneous removal of both pollutants from co-contaminated feed is found to be greater than that in single-feed system under identical experimental conditions. Tested under flow conditions, CNW-gCN/ACF shows approximately the same rates of oxidation and reduction as prevalent under batch conditions, indicating the efficient immobilization of the nanocatalyst particles in ACF, which not only prevents elution of the catalyst but also improves its reusability. The toxicity data indicate the treated water samples to be non-toxic. The current study provides an efficient method for developing supported nanomaterial photocatalysts for treating flowing co-contaminated wastewater.

Development of ESAT-6 Based Immunosensor for the Detection of Mycobacterium tuberculosis.

Early secreted antigenic target of 6 kDa (ESAT-6) has recently been identified as a biomarker for the rapid diagnosis of tuberculosis. We propose a stable and reusable immunosensor for the early diagnosis of tuberculosis based on the detection and quantification of ESAT-6 via cyclic voltammetry (CV). The immunosensor was synthesized by polymerizing aniline dispersed with the reduced graphene oxide (rGO) and Ni nanoparticles, followed by surface modification of the electroconductive polyaniline (PANI) film with anti-ESAT-6 antibody. Physicochemical characterization of the prepared materials was performed by several analytical techniques, including FE-SEM, EDX, XRD, FT-IR, Raman, TGA, TPR, and BET surface area analysis. The antibody-modified Ni-rGO-PANI electrode exhibited an approximately linear response (R2 = 0.988) towards ESAT-6 during CV measurements over the potential range of -1 to +1 V. The lower detection limit for ESAT-6 was approximately 1.0 ng mL-1. The novelty of this study includes the development of the reusable Ni-rGO-PANI-based electrochemical immunosensor for the early diagnosis of tuberculosis. Furthermore, this study successfully demonstrates that electro-conductive PANI may be used as a polymeric substrate for Ni nanoparticles and rGO.

An insight into the bioelectrochemical photoreduction of CO2 to value-added chemicals.

Goal of sustainable carbon neutral economy can be achieved by designing an efficient CO2 reduction system to generate biofuels, in particular, by mimicking the mechanism of natural photosynthesis using semiconducting nanomaterials interfaced with electroactive bacteria (EAB) in a photosynthetic microbial electrosynthesis (PMES) system. This review paper presents an overview of the recent advancements in the biohybrid photoanode and photocathode materials. We discuss the reaction mechanism observed at photoanode and photocathode to enhance our understanding on the solar driven MES. We extend the discussion by showcasing the potential activity of EABs toward high selectivity and production rates for desirable products by manipulating their genomic sequence. Additionally, the critical challenges associated in scaling up the PMES system including the strategies for diminution of reactive oxygen species, low solubility of CO2 in the typical electrolytes, low selectivity of product species are presented along with the suggestions of alternative strategies to achieve economically viable generation of (bio)commodities.

A nickel oxide-decorated in situ grown 3-D graphitic forest engrained carbon foam electrode for microbial fuel cells.

A facile and single-step nickel oxide-dispersed in situ grown 3-D graphitic forest engrained carbon foam (NiO-CNF-CF)-based electrode was fabricated for high-performance microbial fuel cells (MFCs). The metal oxide, graphitic contents, biocompatibility, stability and large surface area available in the material for biofilm formation rendered the prepared electrode competent for wastewater treatment and bioenergy (0.79 V and 1.955 W m-2) generation with a coulombic efficiency of 85.66%.

Efficient electro-oxidation of diclofenac persistent organic pollutant in wastewater using carbon film-supported Cu-rGO electrode.

Gradually increasing concentrations of diclofenac (DCF), a widely used anti-inflammatory drug, in water bodies is an emerging concern because of the persistent characteristics and harmful environmental impact of the drug molecule. In this study, electro-oxidation using a novel copper (Cu) - reduced graphene oxide (rGO) electrode is indicated to be an efficient technology for treating DFC-laden wastewater. The Cu-rGO dispersed carbon film (∼1 mm thickness) is synthesized by carbonization and H2-reduction of a phenolic polymeric film in situ dispersed with a Cu salt and GO. The synthesized self-standing carbon film electrode is used for electro-oxidation of aqueous DCF. Analytical microscopic techniques are used to study the physicochemical properties of the material. Cyclic voltammetry analysis shows the prepared electrode generating a high oxidative current response. Approximately 100% DCF degradation is measured within 1 h at 1 V constant biased potential. Dual roles of Cu-rGO are presented as rGO facilitating direct oxidation via enhanced electron mobility at the electrode surface and Cu nanoparticles (NPs) participating in indirect oxidation by generating OH radicals in aqueous phase. The Cu NPs show an over-potential of -0.5 V vs. Ag/AgCl (100 mM KCl) for oxygen evolution, indicating indirect oxidation of DCF. The high non-faradic current density of 4 mA cm-2 generated at the positive potential (1 V) indicates direct oxidation of DCF. This study clearly indicates electro-oxidation using the Cu-rGO-dispersed carbon film electrode to be an efficient technique for remediation of pharmaceutical pollutants-contaminated wastewater.

Simultaneous scavenging of Cr(VI) from soil and facilitation of nutrient uptake in plant using a mixture of carbon microfibers and nanofibers.

Plant growth and yield are adversely affected by the uptake of toxic hexavalent chromium (Cr(VI)) from soil. The present study describes a facile technique to minimize the uptake of Cr(VI) by chickpea (Cicer arietinum) plant from soil using microporous activated carbon microfiber (ACF). Simultaneously, nano-sized carbon nanofibers (CNFs), grown over the ACF substrate, are used as an efficient carrier of the Cu micronutrient from soil to root, shoot and leaf of the plants. Adsorption, seed germination and plant growth experiments are performed in Cr-stressed medium. The ACF, used as the adsorbent for Cr(VI) in metal-stressed soil (100 mg Cr kg-1 of soil) shows the metal loading of ∼23 mg g-1. Cr(VI) up to 50 mg L-1 concentration causes no stress during germination of chickpea seeds in Murashige and Skoog (MS) medium. A dose of 500 mg-mixture (treatment) per kg-soil increases root and shoot lengths by 52 and 11%, respectively than the control, during plant growth in the metal-stressed soil, attributed to an effective translocation of Cu-CNF through plant cells. Whereas Cr uptake by plant decrease to ∼46%, Cu uptake increase up to ∼120% in comparison to control by the mixture treatment. Protein and chlorophyll contents also significantly increased (*p < 0.05) with the application of treatment. The data clearly show that the mixture of ACF and Cu-CNF can be successfully used for the simultaneous scavenging of Cr(VI) from soil by adsorption over ACF and increased uptake of Cu by plants using the CNFs as the micronutrient carrier.

Synthesis of Yeast-Immobilized and Copper Nanoparticle-Dispersed Carbon Nanofiber-Based Diabetic Wound Dressing Material: Simultaneous Control of Glucose and Bacterial Infections.

Diabetic wounds are instantaneously prone to the bacterial infections that can delay healing process. An efficient wound dressing material is critical to a fast healing of wounds in diabetic patients. The present study focuses on the synthesis of the yeast extract (YE)-immobilized and copper (Cu) nanoparticle (NP)-dispersed carbon nanofibers (CNFs) as a potential diabetic wound dressing material. The biological assays, namely, platelet aggregation, hemolysis, cells viability, and proliferation of macrophage cells show the prepared biomaterial to be noncytotoxic. Chemical tests performed on the material show a significant consumption of glucose, whereas the antibacterial tests show the material to be efficiently inhibiting the E. coli and S. aureus strains, ascribed to the antibacterial characteristics of the immobilized YE and the dispersed Cu-NPs, respectively, in the CNFs. To analyze the in vivo wound healing property, a 1 cm circular full thickness skin wound was created in diabetic Wistar rats. The wounds with dressings showed enhanced healing rate compared to those in the control animals (without dressing). Maximum healing (wound closure) was observed in the Cu-CNF-YE (95%) group, followed by Cu-CNF (94%), activated carbon micronanofibers (ACF-CNF) (87%), and control animals with only 74% healing. The method of preparing Cu-CNF-YE metal-enzyme-fabric described in this study is facile, and the composite can be applied as an effective dressing material for diabetic wounds.

Highly effective Cu/Zn-carbon micro/nanofiber-polymer nanocomposite-based wound dressing biomaterial against the P. aeruginosa multi- and extensively drug-resistant strains.

Pseudomonas aeruginosa (P. aeruginosa) is the most prevalent bacteria in the infections caused by burn, surgery, and traumatic injuries. Emergence of the P. aeruginosa bacterial resistance against various clinical drugs for wound treatment is the major concern nowadays. The present study describes the synthesis of the polyvinyl alcohol (PVA) and cellulose acetate phthalate (CAP) polymeric composite film (~0.2mm thickness) reinforced with the Cu/Zn bimetal-dispersed activated carbon micro/nanofiber (ACF/CNF), as a wound dressing material. The focus is on determining the efficacy of the prepared biomaterial against the multi and extensively drug-resistant P. aeruginosa strains isolated from the burning, surgical, and traumatic injury-wounds. The primary synthesis steps for the biomaterial include the mixing of a blend of CAP powder and the asymmetrically distributed Cu/Zn bimetals in ACF/CNF, into the polymerization reaction mixture of PVA. Biochemical tests showed that the prepared composite material significantly enhanced the in-vitro blood clotting rate, platelet aggregation, and macrophage cell proliferation, indicating the suitability of the material as a fast wound healer. The antibacterial tests performed against the P. aeruginosa strains showed that the material effectively suppressed the bacterial growth, with the bimetal nanoparticles dispersed in the material serving as an antibacterial agent. The PVA/CAP polymer composite served as an encapsulating agent providing a slow release of the nanoparticles, besides increasing the hemostatic properties of the biomaterial. The ACF/CNF served as a support to the dispersed bimetal nanoparticles, which also provided a mechanical and thermal stability to the material. Experimentally demonstrated to be biocompatible, the prepared metal-carbon-polymer nanocomposite in this study is an effective dressing material for the P. aeruginosa-infected wounds.

Aqueous phase adsorption of different sized molecules on activated carbon fibers: Effect of textural properties.

The effect that the textural properties of rayon-based activated carbon fibers (ACFs), such as the BET surface area and pore size distribution (PSD), have on the adsorption of differently sized molecules, namely, brilliant yellow (BY), methyl orange (MO) and phenol (PH), was investigated in the aqueous phase. ACF samples with different BET areas and PSDs were produced by steam-activating carbonized fibers for different activation times (0.25, 0.5, and 1 h). The samples activated for 0.25 h were predominantly microporous, whereas those activated for relatively longer times contained hierarchical micro-mesopores. The adsorption capacities of the ACFs for the adsorbate increased with increasing BET surface area and pore volume, and ranged from 51 to 1306 mg/g depending on the textural properties of the ACFs and adsorbate size. The adsorption capacities of the hierarchical ACF samples followed the order BY > MO > PH. Interestingly, the number of molecules adsorbed by the ACFs followed the reverse order: PH > MO > BY. This anomaly was attributed to the increasing molecular weight of the PH, MO and BY molecules. The equilibrium adsorption data were described using the Langmuir isotherm. This study shows that suitable textural modifications to ACFs are required for the efficient aqueous phase removal of an adsorbate.

Copper/zinc bimetal nanoparticles-dispersed carbon nanofibers: A novel potential antibiotic material.

Copper (Cu) and zinc (Zn) nanoparticles (NPs) were asymmetrically distributed in carbon nanofibers (CNFs) grown on an activated carbon fiber (ACF) substrate by chemical vapor deposition (CVD). The CVD conditions were chosen such that the Cu NPs moved along with the CNFs during tip-growth, while the Zn NPs remained adhered at the ACF. The bimetal-ACF/CNF composite material was characterized by the metal NP release profiles, in-vitro hemolytic and antibacterial activities, and bacterial cellular disruption and adhesion assay. The synergetic effects of the bimetal NPs distributed in the ACFs/CNFs resulted from the relatively slower release of the Cu NPs located at the tip of the CNFs and faster release of the Zn NPs dispersed in the ACF. The Cu/Zn-grown ACFs/CNFs inhibited the growth of the Gram negative Escherichia coli, Gram positive Staphylococcus aureus, and Methicillin resistance Staphylococcus aureus bacterial strains, with superior efficiency (instant and prolonged inhibition) than the Cu or Zn single metal-grown ACFs/CNFs. The prepared bimetal-carbon composite material in this study has potential to be used in different biomedical applications such as wound healing and antibiotic wound dressing.

Carbon bead-supported nitrogen-enriched and Cu-doped carbon nanofibers for the abatement of NO emissions by reduction.

Carbon nanofibers (CNFs) were grown over highly porous (∼1750 m(2)/g-surface area) carbon beads (∼0.8 mm), using catalytic chemical vapor deposition (CVD). The carbon beads were produced by the pre-oxidation, carbonization and activation of the phenolic beads that were synthesized using the suspension polymerization. The beads were doped in situ with copper (Cu) during the polymerization reaction. The carbon beads decorated with the CNFs were treated with pyridine to increase the nitrogen (N) contents of the material. The N-enriched CNFs and Cu nanoparticles (NPs)-doped carbon beads (N-Cu-CNF/CBs) were used for the removal of nitric oxide (NO) by reduction. In its dual role, Cu catalyzed the growth of the CNFs during CVD, and also, the reduction reaction. Approximately 86% of NO conversion was achieved for 400 ppm-NO concentration over 1 g of the prepared catalyst at 500 °C. The high catalytic activity was attributed to the combined roles of the Cu NPs, reactive CNFs and N-containing surface functional groups in the material. The prepared carbon bead-supported CNFs in this study are for the first time effectively used as the catalyst for the NO reduction without requiring ammonia or urea.

Preparation of asymmetrically distributed bimetal ceria (CeO2) and copper (Cu) nanoparticles in nitrogen-doped activated carbon micro/nanofibers for the removal of nitric oxide (NO) by reduction.

A novel multi-scale web of carbon micro/nanofibers (ACF/CNF) was prepared by the catalytic chemical vapor deposition (CCVD), in which CeO2 and Cu nanoparticles (NPs) were in-situ incorporated during a synthesis step. The CVD temperature was adjusted such that the prepared material had asymmetric distribution of the bimetals, with the Cu NPs located at the tips of the CNFs and the CeO2 particles adhered to the surface of the ACF substrate. The prepared bimetals-dispersed web of ACF/CNF was treated with pyridine and the surface functionalized material was applied for the removal of NO by reduction. The complete reduction of NO was achieved at 500°C and for 400ppm NO concentration. Whereas the Cu NPs acted as the catalyst for the reduction, CeO2 facilitated the incorporation of nitrogen from the pyridine source into the ACF/CNF surface. The produced nitrogen containing surface functional groups enhanced the reactivity of the material toward the NO. The bimetals CeO2 and Cu nanoparticles (NPs)-dispersed ACF/CNF produced in this study is a potential candidate for effectively removing NO by reduction, without requiring urea or ammonia used in conventional abatement methods.

Depinning of drops on inclined smooth and topographic surfaces: experimental and lattice Boltzmann model study.

In this study, the dynamics of initially stationary liquid drops on smooth and topographic inclined silicon surfaces was investigated experimentally and by lattice Boltzmann simulations. The transient contact angles and the critical angle of inclination were measured systematically for different liquids, drop sizes, and surfaces having different wettability and surface roughness. In general, the critical angle of inclination is larger for hydrophilic than for hydrophobic surfaces, irrespective of the liquids, and increases with increasing contact angle hysteresis and decreasing drop sizes. A two-phase liquid-vapor lattice Boltzmann model based on the Shan and Chen approach was developed for two dimensions which incorporates the wetting and topographic characteristics of the surface. The simulation results matched the experimentally found features quantitatively and allowed one to explore the roll-off behavior even in cases that can hardly be accessed experimentally.

Multi-scale carbon micro/nanofibers-based adsorbents for protein immobilization.

In the present study, different proteins, namely, bovine serum albumin (BSA), glucose oxidase (GOx) and the laboratory purified YqeH were immobilized in the phenolic resin precursor-based multi-scale web of activated carbon microfibers (ACFs) and carbon nanofibers (CNFs). These biomolecules are characteristically different from each other, having different structure, number of parent amino acid molecules and isoelectric point. CNF was grown on ACF substrate by chemical vapor deposition, using Ni nanoparticles (Nps) as the catalyst. The ultra-sonication of the CNFs was carried out in acidic medium to remove Ni Nps from the tip of the CNFs to provide additional active sites for adsorption. The prepared material was directly used as an adsorbent for proteins, without requiring any additional treatment. Several analytical techniques were used to characterize the prepared materials, including scanning electron microscopy, Fourier transform infrared spectroscopy, BET surface area, pore-size distribution, and UV-vis spectroscopy. The adsorption capacities of prepared ACFs/CNFs in this study were determined to be approximately 191, 39 and 70 mg/g for BSA, GOx and YqeH, respectively, revealing that the carbon micro-nanofibers forming synthesized multi-scale web are efficient materials for the immobilization of protein molecules.

Synthesis of phenolic precursor-based porous carbon beads in situ dispersed with copper-silver bimetal nanoparticles for antibacterial applications.

Copper (Cu) and silver (Ag) bimetal-dispersed polymeric beads (~0.7 mm) were synthesized by suspension polymerization using phenol and formaldehyde monomers. The Cu:Ag bimetal nanoparticles (Nps) were incorporated into the polymeric matrix at the incipience of gel formation during polymerization using an anionic surfactant. The prepared bimetal-doped polymeric beads were carbonized, activated using steam, and reduced in a hydrogen atmosphere to produce metal Nps-doped porous carbon beads. The prepared bimetal (Cu and Ag) Nps-doped beads exhibited significantly larger anti-bacterial activities than single-(Cu or Ag) metal-doped beads for both gram-positive Staphylococcus aureus and gram-negative Escherichia coli bacteria. The prepared materials contained the total optimized amounts of Cu and Ag. These amounts were smaller (approximately half) than the amount of single metal (Cu or Ag) required for preparing single-metal-doped beads. Although Cu Nps exhibit lesser antibacterial activity than Ag Nps, it enhanced the porosity of the beads. The prepared bimetal beads remained effective for 120 h, completely inhibiting the bacterial growth, and therefore, they are potential antibacterial agents for water purification.

Axisymmetric multiphase lattice Boltzmann method.

A lattice Boltzmann method for axisymmetric multiphase flows is presented and validated. The method is capable of accurately modeling flows with variable density. We develop the classic Shan-Chen multiphase model [Phys. Rev. E 47, 1815 (1993)] for axisymmetric flows. The model can be used to efficiently simulate single and multiphase flows. The convergence to the axisymmetric Navier-Stokes equations is demonstrated analytically by means of a Chapmann-Enskog expansion and numerically through several test cases. In particular, the model is benchmarked for its accuracy in reproducing the dynamics of the oscillations of an axially symmetric droplet and on the capillary breakup of a viscous liquid thread. Very good quantitative agreement between the numerical solutions and the analytical results is observed.

Development of bimetal-grown multi-scale carbon micro-nanofibers as an immobilizing matrix for enzymes in biosensor applications.

This study describes the development of a novel bimetal (Fe and Cu)-grown hierarchical web of carbon micro-nanofiber-based electrode for biosensor applications, in particular to detect glucose in liquids. Carbon nanofibers (CNFs) are grown on activated carbon microfibers (ACFs) by chemical vapor deposition (CVD) using Cu and Fe as the metal catalysts. The transition metal-fiber composite is used as the working electrode of a biosensor applied to detect glucose in liquids. In such a bi-nanometal-grown multi-scale web of ACF/CNF, Cu nanoparticles adhere to the ACF-surface, whereas Fe nanoparticles used to catalyze the growth of nanofibers attach to the CNF tips. By ultrasonication, Fe nanoparticles are dislodged from the tips of the CNFs. Glucose oxidase (GOx) is subsequently immobilized on the tips by adsorption. The dispersion of Cu nanoparticles at the substrate surface results in increased conductivity, facilitating electron transfer from the glucose solution to the ACF surface during the enzymatic reaction with glucose. The prepared Cu-ACF/CNF/GOx electrode is characterized for various surface and physicochemical properties by different analytical techniques, including scanning electron microscopy (SEM), electron dispersive X-ray analysis (EDX), Fourier-transform infrared spectroscopy (FTIR), BET surface area analysis, and transmission electron microscopy (TEM). The electrochemical tests show that the prepared electrode has fast response current, electrochemical stability, and high electron transfer rate, corroborated by CV and calibration curves. The prepared transition metal-based carbon electrode in this study is cost-effective, simple to develop, and has a stable immobilization matrix for enzymes.

Preparation of novel carbon microfiber/carbon nanofiber-dispersed polyvinyl alcohol-based nanocomposite material for lithium-ion electrolyte battery separator.

A novel nanocomposite polyvinyl alcohol precursor-based material dispersed with the web of carbon microfibers and carbon nanofibers is developed as lithium (Li)-ion electrolyte battery separator. The primary synthesis steps of the separator material consist of esterification of polyvinyl acetate to produce polyvinyl alcohol gel, ball-milling of the surfactant dispersed carbon micro-nanofibers, mixing of the milled micron size (~500 nm) fibers to the reactant mixture at the incipience of the polyvinyl alcohol gel formation, and the mixing of hydrophobic reagents along with polyethylene glycol as a plasticizer, to produce a thin film of ~25 µm. The produced film, uniformly dispersed with carbon micro-nanofibers, has dramatically improved performance as a battery separator, with the ion conductivity of the electrolytes (LiPF6) saturated film measured as 0.119 S-cm(-1), approximately two orders of magnitude higher than that of polyvinyl alcohol. The other primary characteristics of the produced film, such as tensile strength, contact angle, and thermal stability, are also found to be superior to the materials made of other precursors, including polypropylene and polyethylene, discussed in the literature. The method of producing the films in this study is novel, simple, environmentally benign, and economically viable.

Preparation of surfactant-mediated silver and copper nanoparticles dispersed in hierarchical carbon micro-nanofibers for antibacterial applications.

The antibacterial potential of copper (Cu) and silver (Ag) nanoparticles dispersed in a phenolic resin precursor-based multi-scale web of carbon microfibers (ACFs) and nanofibers (CNFs) was assessed in this study. The multi-scale web of ACF/CNF was prepared by growing the CNFs on the ACF substrate by chemical vapor deposition (CVD). The Ag or Cu nanoparticles were used as the catalyst, and acetylene (C2H2) gas was used as the carbon source. An anionic surfactant, sodium dodecyl sulfate (SDS), was used for the preparation of the Cu/Ag-ACF composites to prevent the agglomeration of Cu(II) and Ag(I) ions and achieve a uniform mono-dispersion during the impregnation step. The prepared composites with Cu and Ag dispersed in the ACF and ACF/CNF were characterized using several analytical techniques, including atomic absorption spectroscopy (AAS), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and thermal programming reduction (TPR). The antibacterial properties of the prepared multi-scale or hierarchical structures were evaluated against the gram-negative bacteria Escherichia coli (E. coli) and the gram-positive bacteria Staphylococcus aureus (S. aureus). The results revealed that the prepared Ag-ACF/CNFs were highly effective against these bacteria, achieving a complete inhibition of bacterial growth for over 72 hours.