Raman Spectroscopy Research Articles

In Situ Symbiosis of Cerium Oxide Nanophase for Enhancing the Oxygen Electrocatalysis Performance of Single-Atom Fe─N─C Catalyst with Prolonged Stability for Zinc-Air Batteries.

The Fenton reaction, induced by the H2O2 formed during the oxygen reduction reaction (ORR) process leads to significant dissolution of Fe, resulting in unsatisfactory stability of the iron-nitrogen-doped carbon catalysts (Fe-NC). In this study, a strategy is proposed to improve the ORR catalytic activity while eliminating theeffectof H2O2 by introducing CeO2 nanoparticles. Transmission electron microscopy and subsequent characterizations reveal that CeO2 nanoparticles are uniformly distributed on the carbon substrate, with atomically dispersed Fe single-atom catalysts (SACs) adjacent to them. CeO2@Fe-NC achieves a half-wave potential of 0.89V and a limiting current density of 6.2mAcm-2, which significantly outperforms Fe-NC and commercial Pt/C. CeO2@Fe-NC also shows a half-wave potential loss of only 1% after 10000 CV cycles, which is better than that of Fe-NC (7%). Further, H2O2 elimination experiments show that the introduction of CeO2 significantly accelerate the decomposition of H2O2. In situ Raman spectroscopy results suggest that CeO2@Fe-NC significantly facilitates the formation of ORR intermediates compared with Fe-NC. The Zn-air batteries utilizing CeO2@Fe-NC cathodes exhibit satisfactory peak power density and open-circuit voltage. Furthermore, theoretical calculations show that the introduction of CeO2 enhances the ORR activity of Fe-NC SAC. This study provides insights for optimizing SAC-based electrocatalysts with high activity and stability.

Tailoring Electrochemical Water Oxidation Activity from the Isostructural Series of Alkaline‐Stable Bimetallic Fe,Ni‐Azolate Metal–Organic Frameworks

AbstractIncorporating electrocatalytic active sites into the reticular framework allows for the design of novel catalytic structures promoting desired catalytic reactions with efficient mass transfer. However, to fully exploit the advantages of such a framework, it is crucial to ensure the electrochemical stability of the material. In this context, alkaline‐stable bimetallic MxNi2‐xCl2BTDD (M = Fe, Co) metal–organic frameworks (MOFs) are employed as electrocatalysts for alkaline water oxidation reaction (WOR) to understand the correlation between secondary metal incorporation and catalytic activity changes. For a specific Fe ratio within the MOF, the optimal catalytic activity is achieved at an overpotential of 315 mV at a WOR current density of 10 mA cm−2geo. Based on its well‐defined crystal structure and uniformly arranged metal nodes, which are not limited to specific facets, the cooperative electrocatalytic mechanism during the faradaic WOR process is investigated through operando Raman spectroscopy and density functional theory calculations. These results enable the interpretation of the electrochemical WOR mechanism based on MOF, providing a further fundamental understanding of electrocatalytic activity in bimetallic systems.

Elucidating and Minimizing the Space‐Charge Layer Effect between NCM Cathode and Li6PS5Cl for Sulfide‐Based Solid‐State Lithium Batteries

AbstractThe electrochemical performance of all‐solid‐state lithium batteries (ASSLBs) can be significantly improved by addressing the challenges posed by space charge layer (SCL) effect, which plays a crucial role in determining Li+ ions transport kinetic at cathodic interface. Therefore, it is critical to realize the in situ inspection and visualization of SCL behaviors for solving sluggish Li+ ions transport issues, despite remaining grant challenges. Therewith, the well‐defined model of LiNbO3‐coated NCM (NCM@LNO) cathode is constructed and assembled for the representative Li6PS5Cl‐based ASSLBs, which not only ensures excellent cathodic compatibility, but also preferably enables the better monitoring of Li+ ions transport kinetics. Combining ex situ analysis with DFT calculation, the formation and evolution mechanism of SCL are comprehensively understood, and the relationship between well‐controlled SCL configuration and Li+ electrochemical behavior has been also further illustrated and established through the operando Raman spectroscopy. On these grounds, the preferred NCM@LNO cathodes acquire the enhanced discharge capacity of 90.6% (144.8 mAh g−1) after 100 cycles and it can still deliver the exceptional capacity of 136.2 mAh g−1 after 800 cycles in ASSLBs. Hence, the research will pave up a new perspective for fundamental scientific insight of the SCL and reasonable tailoring of cathodic interface for high‐efficiency ASSLBs.

In-situ activation of three-dimensional porous NiFe alloy: Synergistic NiFe hydroxide/alloy as composite active sites for efficiently catalyzing alkaline water splitting

The strategic engineering of bifunctional catalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media is critical for water-splitting technologies. This study presented a catalyst consisting of in situ grown nickel iron (NiFe) hydroxide/porous alloy composite catalytic sites on a nickel foam (NF) substrate. Initially, a porous NiFe alloy was electrodeposited onto NF, employing hydrogen (H2) bubbles as dynamic templates to induce a three-dimensional (3D) architecture. Subsequently, ultrathin layers of NiFe hydroxide nanosheets were synthesized in situ via electrochemical activation. The distinctive porous structure, coupled with the in-situ activated nanosheets, augmented the exposure of active sites, optimized electrolyte interaction, and expedited the expulsion of gaseous byproducts, collectively enhancing the kinetics of water electrolysis. The resultant a-Ni2Fe/NF demonstrated superior OER/HER activities, achieving overpotentials of merely 240mV for OER and 183mV for HER at a current density of 100mAcm-2 in alkaline solution. Moreover, a voltage of just 1.53V was requisite to attain a current density of 10mAcm-2 for overall water splitting. Operando Raman spectroscopy revealed the formation of NiOOH and FeOOH active phases during HER, indicating the hydroxide’s role in adsorbing hydroxyl groups and shielding NiFe alloy’s H⁎ adsorption sites from oxidation. The presence of the more reactive β-NiOOH phase was discerned during OER process, acting as an intermediate. This straightforward yet efficacious strategy heralded a new paradigm in the design of NiFe-based bifunctional catalysts, significantly bolstering the efficiency of water electrolysis catalysis.

Lattice defects distribution of H+ implanted 4H-SiC investigated by deep-ultraviolet Raman spectroscopy

Lattice defects distribution of H+ implanted 4H-SiC investigated by deep-ultraviolet Raman spectroscopy

A systematic study of solvation structure of asymmetric lithium salts in water.

Aqueous electrolytes are promising in large-scale energy storage applications due to intrinsic low toxicity, non-flammability, high ion conductivity, and low cost. However, pure water's narrow electrochemical stability window (ESW) limits the energy density of aqueous rechargeable batteries. Water-in-salt electrolytes (WiSE) proposal has expanded the ESW to over 3 V by changing electrolyte solvation structure. The limited solubility and WIS electrolyte crystallization have been persistent concerns for imide-based lithium salts. Asymmetric lithium salts compensate for the above flaws. However, studying the solvation structure of asymmetric salt aqueous electrolytes is rare. Here, we applied small-angle X-ray scattering (SAXS) and Raman spectroscope to reveal the solvation structure of imide-based asymmetric lithium salts. The SAXS spectra show the blue shifts of the lower q peak with decreased intensity as the increasing of concentration, indicating a decrease in the average distance between solvated anions. Significantly, an exponential decrease in the d-spacing as a function of concentration was observed. In addition, we also applied the Raman spectroscopy technique to study the evolutions of solvent-separated ion pairs (SSIPs), contacted ion pairs (CIPs), and aggregate ions (AGGs) in the solvation structure of asymmetric salt solutions.&#xD.

Polymer blending and nanophotocatalyst loading synergy in visible light‐driven photocatalytic PES/SPSf mixed matrix membranes

AbstractThe synergy of polymer blending and loading photocatalytic titania–amorphous carbon nanotubes (TiO2–aCNT) in tailoring the morphological, surface, and optoelectrical properties of membranes is investigated. High energy band gap (Eg) polyethersulfone (PES), and low Eg sulfonated polyethersulfone (SPSf) polymer blends were loaded with TiO2–aCNT nanocomposite fillers. SEM reveals membranes consisting of a selective layer, a dense sublayer and a spongy layer with the latter two consisting of a network of nanofibers whose diameters decrease with increasing TiO2–aCNT loading. The downshifting in the wavenumbers of sulfonyl and sulfone peaks in Fourier transform infrared and Raman spectra confirms bonding of TiO2–aCNT with PES/SPSf via these groups. Blending PES with SPSf decreases the Eg of the membranes while loading TiO2–aCNT produces a second band edge corresponding to = 2.8 eV. Suppression of charge recombination in membranes is realized at 1.2 filler wt.%. Charge separation occurrs via shuttling of the positive holes to the aCNTs and valence band of TiO2 while electrons are shuttled to the conduction bands of PES and SPSf. Electron impedance spectroscopy shows TiO2–aCNT loading reduces polymer membrane resistance to charge transport. Dye degradation up to 85% is realized under direct sunlight irradiation accompanied by mineralization.

Adsorption, Sensor Properties, AIM Analysis, Docking of an Anticancer Drug Benzamide on Nanocones: SERS, Solvent Effects and DFT Investigation

Using first principles, the electrical response of carbon nanocones (NC) to the drug benzamide (BZE) was investigated using density functional theory (DFT). The adsorption energies of BZE at the nanocone’s bottom (Complex I), side (Complex II), and top (Complex III) are −88.35 kcal/mol, −45.46 kcal/mol and −48.73 kcal/mol. The two other adsorptions, Complexes II and III are physisorption, however, the high value of Eads in the case of Complex I with the drop in bond lengths suggests that Complex I adsorption is chemisorption. The electrical conductivity has risen as a result of the considerable decrease in the nanocone energy gap (from 0.63 eV to 0.61 eV, 0.61 eV and 0.60 eV) caused by the adsorption of BZE. It suggests that the nanocones would be a good fit for the electronic sensors and an appropriate choice for BZE detection. Additionally, the BZE adsorption influences the nanocone’s workfunction, which is reduced by approximately 45.19%, 2.8% and 2.05% for complexes I to III. This suggests that the nanocone could be a workfunction-based sensor for the detection of BZE. The increase in binding affinity in complexes reveals that the nanocones will act as a drug delivery carrier. Theoretically, anticipated Raman spectra of BZE and complexes show SERS activity and inactive normal Raman modes are active in the Raman spectrum of complexes. Compounds II and III exhibit weak noncovalent interactions (NCI) and due to the presence of covalent bonding interaction in compound I, significant changes in other bonding and nonbonding electron densities are observed compared to compounds II and III.

Tuning of thermoelectric performance by modulating vibrational properties in Ni-doped Sb2Te3.

Sb2Te3, a binary chalcogenide-based 3D topological insulator, attracts significant attention for its exceptional thermoelectric performance. We report the vibrational properties of magnetically doped Sb2Te3 thermoelectric material. Ni doping induces defect/disorder in the system and plays a positive role in engineering the thermoelectric properties through tuning the vibrational phonon modes. Synchrotron powder X-ray diffraction study confirms good crystalline quality and single-phase nature of the synthesized samples. The change in structural parameters, including Biso and strain, further corroborate with structural disorder. Detailed modification of phonon modes with doping and temperature variation is analysed from temperature-dependent Raman spectroscopic measurement. Compressive lattice strain is observed from the blue shift of Raman peaks owing to Ni incorporation in Sb site. An attempt is made to extract the lattice thermal conductivity from total thermal conductivity estimated through optothermal Raman studies. Hall concentration data support the change in temperature-dependent resistivity and thermopower. Remarkable increase in thermopower is observed after Ni doping. Simulation of the Pisarenko model, indicating the convergence of the valence band, explains the observed enhancement of thermopower in Sb2-xNixTe3. The energy gap between the light and heavy valence band at Γ point is found to be 30 meV (for Sb2Te3), which is reduced to 3 meV (in Sb1.98Ni0.02Te3). A significant increase in thermoelectric power factor is obtained from 715 μWm-1K-2 for pristine Sb2Te3 to 2415 μWm-1K-2 for Ni-doped Sb2Te3 sample. Finally, the thermoelectric figure of merit, ZT is found to increase by four times in Sb1.98Ni0.02Te3 than that of its pristine counterpart.

The Effect of 147 MeV 84Kr and 24.5 MeV 14N Ions Irradiation on the Optical Absorption, Luminescence, Raman Spectra and Surface of BaFBr Crystals

Today, BaFBr crystals activated by europium ions are used as detectors that store absorbed energy in metastable centers. In these materials, the image created by X-ray irradiation remains stable in the dark for long periods at room temperature. As a result, memory image plates are created, and they are extended to other types of ionizing radiation as well. Despite significant progress towards X-ray storage and readout of information, the mechanisms of these processes have not been fully identified to date, which has hindered the efficiency of this class of phosphors. In this study, using photoluminescence (PL), optical absorption (OA), Raman spectroscopy (RS), and atomic force microscopy (AFM), the luminescence of oxygen vacancy defects to BaFBr crystals irradiated with 147 MeV 84Kr and 24.5 MeV 14N ions at 300 K to fluences (1010–1014) ion/cm2 was investigated. BaFBr crystals were grown by the Shteber method on a special device. Energy-dispersive X-ray spectroscopy (EDX) analysis revealed the presence of Ba, Br, F, and O. The effect of oxygen impurities present in the studied crystals was considered. The analysis of the complex PL band, depending on the fluence and type of ions, showed the formation of three types of oxygen vacancy defects. Macrodefects (tracks) and aggregates significantly influence the luminescence of oxygen vacancy defects. The creation of hillocks and tracks in BaFBr crystals irradiated with 147 MeV 84Kr ions is shown for the first time. Raman spectra analysis confirmed that BaFBr crystals were amorphized by 147 MeV 84Kr ions due to track overlap, in contrast to samples irradiated with 24.5 MeV 14N ions. Raman and absorption spectra demonstrated the formation of hole and electron aggregate centers upon swift heavy ions irradiation.

Performance assessment of portable Raman spectroscopy in determining ecstasy tablets

AbstractEcstasy tablets, a type of common street drug originally consisting of 3,4‐methylenedioxymethamphetamine (MDMA), provide stimulant and hallucinogen psychoactive effects. They are frequently found in nightclubs, musical festivals or other recreational events believed to create a relaxing experience for the users. From a forensic perspective, when the drug of abuse is suspected in such scenarios, the law enforcement personnel would then require an easy‐to‐perform, quick and accurate method to detect the existence of such controlled substance prior to the seizure and subsequent forensic examination. In this study, we assessed the performance of a portable Raman spectroscopy as the primary aid in determining ecstasy tablets at the point of use. A total of 130 ecstasy tablet samples were analysed by Raman spectroscopy and characterised by gas chromatography–mass spectrometry (GC–MS). Active chemical substances and cutting agents detected by the two instrumentations were then compared. The performance of Raman spectroscopy was further assessed in terms of its accuracy, sensitivity and specificity, corresponding to the analysis results obtained from GC–MS analysis. Overall, portable Raman Spectroscopy used in this study shows an accuracy of 85.4% in analysing ecstasy tablets obtained from case samples, while the sensitivity and specificity were determined as 85.2% and 100%, respectively. No false positives for MDMA or other drugs were reported. Our results show that portable Raman spectroscopy is a suitable technique for targeted determination of the presence of ecstasy tablets, especially in forensic cases that require non‐destructive, rapid and mass screening during on‐site testing by law enforcement personnel.

Raman Spectroscopy for the Time since Deposition Estimation of a Menstrual Bloodstain

Forensic chemistry plays a crucial role in aiding law enforcement investigations by applying analytical techniques for the analysis of evidence. While bloodstains are frequently encountered at crime scenes, distinguishing between peripheral and menstrual bloodstains presents a challenge. This is due to their similar appearance post-drying. Raman spectroscopy has emerged as a promising technique capable of discriminating between the two types of bloodstains, offering invaluable probative information. Moreover, estimating the time since deposition (TSD) of bloodstains aids in crime scene reconstruction and prioritizing what evidence to collect. Despite extensive research focusing on TSD estimations, primarily in peripheral bloodstains, a crucial gap exists in determining the TSD of menstrual bloodstains. This study demonstrates how Raman spectroscopy effectively analyzes biological samples like menstrual blood, showing similar aging patterns to those of peripheral blood and provides proof-of-concept models for determining the TSD of menstrual blood. While this work shows promising results for creating a universal model for bloodstain age determination, further testing with more donors needs to be conducted before the implementation of this method into forensic practice.

Effect of graphene oxide loaded on TiO2-nanotube-modified Ti on inflammatory responses

Although a titanium matrix modified with titanium dioxide nanotube (TNT) arrays can have anti-inflammatory effects in vitro, these effects are limited. In this study, the TNT surface was modified by electrodepositing graphene oxide (GO) to enhance the anti-inflammatory effect of the material. Scanning electron microscopy (SEM), Raman spectroscopy, and x-ray diffraction were used to characterize each of these materials. Cell Counting Kit-8 (CCK-8) was used to determine the cell proliferation status. Enzyme-linked Immunosorbent Assay (ELISA), immunofluorescence staining, and RNA sequencing were used to assess the regulation of inflammation in each group. Raman spectroscopy confirmed that GO was successfully loaded onto the surface. The SEM, ELISA, fluorescence staining, and RNA sequencing results indicated that TNT-GO can effectively inhibit the inflammatory response and induce the M2 polarization of macrophages. TNT-GO can weaken the surface inflammatory responses of materials, suppress the secretion of pro-inflammatory factors, and promote the M2 polarization of macrophages. These advantageous properties render TNT-GO a promising material for dental implants.

A Miniaturized Endoscopic Device Integrating Raman Spectroscopy and Laser Speckle Technology Via an Image Fusion Algorithm for Intraoperative Identification and Functional Protection of Parathyroid Glands

Abstract The importance of parathyroid glands (PGs) protection is increasingly recognized by thyroid surgeons in the field of minimally invasive video-assisted thyroidectomy (MIVAT). However, current techniques for intra-operative identification and vascularity assessment of the PGs are contentious and complex. This study presents the design and validation of a miniaturized device for fusion near-infrared autofluorescence (NIRAF) based on Raman spectroscopy and laser speckle contrast imaging (LSCI) via an image fusion algorithm for functional protection of PGs in the MIVAT. Our light source components include an integrated light emitting diode (LED) light source fiber, an NIRAF optical fiber, an acquisition optical fiber, and a laser speckle optical fiber in the endoscopic system to achieve identification and vascularity assessment of PGs using a single endoscopic probe. It has been validated in ex vivo tissue experiments that the fluorescence intensity detected by the device was equivalent to that of the marker indocyanine green (ICG) in visual images and superior to that of the thyroid and all other tissues in the neck. Based on clinical studies, MIVAT using functional fluorescence endoscopy, compared with the White light pattern group, the NIRAF combined with LSCI modality group increased the number of intra-operative confirmations of the PGs (P < 0.001), declined the decrease in parathyroid hormone (PTH) (P < 0.05) and calcium levels (P < 0.05) on the first postoperative day, and reduced the incidence of symptomatic hypocalcemia (P < 0.05). Our device may reduce the incidence of postoperative permanent hypoparathyroidism. Application of an miniaturized functional fluorescence endoscope for real-time and label-free PGs identification and vascularity assessment in MIVAT could be realized.

Analytical applications of droplet deposition Raman spectroscopy.

The droplet deposition methods in Raman spectroscopy have received considerable attention in the field of analytical sensing focusing on effective pre-concentration of the studied analyte (coffee-ring effect or small spots). This review covers different analytical applications of drop-coating deposition Raman scattering (DCDRS) and droplet deposition surface-enhanced Raman scattering (SERS) spectroscopy. Two main advantages of droplet deposition Raman techniques are considered: the drying-induced segregation of the components from the mixtures (such as body fluids) and the sensitivity of detection of various analytically important molecules. Some recent advanced applications, including clinical cancer diagnosis, are discussed and summarized. Finally, the potential and further perspectives of the droplet deposition Raman methods for analytical studies are introduced.

Congo red dye reduction mediated by the electron (e-) transfer route of BH4- ions using synthesized NiCo2O4/rGO hybrid nanosheets

Abstract The treatment of toxic organic pollutants is extremely important for the conservation of clean air, soil, and water. In this study, (reduced graphene oxide) NiCo2O4/ rGO hybrid nanocomposite was prepared by a facile hydrothermal technique and employed for organic dye degradation from wastewater. The synthesized NiCo2O4/rGO hybrid nanocomposite was studied using FTIR, XRD, SEM, TEM, BET, Raman spectroscopy, and UV-visible. The physical characterizations prove the deposition of NiCo2O4 particles on the rGO surface. The transmission electron microscope image demonstrated that the NiCo2O4 particles with an average size of ~46 nm was dispersed on the rGO surface. The obtained nanoparticles show a higher specific surface area of 56.4 m2/g. Adsorption dynamics as investigated by time and concentration variation show that the adsorption data follows pseudosecond order kinetics and the Langmuir isotherm model, with a maximum adsorption capacity of 106.2 mg/g, indicating homogeneous physiochemical adsorption of CR dye on the adsorbent surface. Besides, the catalytic effectiveness of synthesized nanocomposite towards Congo red (CR) dye reduction mediated by the electron (e-) transfer route of BH4- ions was explained in detail. The electrostatic interaction used between the NiCo2O4/rGO hybrid composite and Congo red increased the degradation effectiveness of the dye sample. 


Cu-doped NiO thin film's structural, optical, and electrical properties and its negative absorption behaviour in the Infra-Red region

NiO undoped and Cu-doped thin films on FTO-coated glass (fluorine-doped tin oxide) are prepared by employing the sol-gel spin coating method. The Cu-doping effect was observed in all the characterized reports such as absorption, transmittance, field emission scanning electron microscope (FESEM), Grazing Incidence X-ray Diffraction (GIXRD), photoluminescence (PL), Raman spectra, current-voltage measurement (IV), and X-ray photoelectron spectroscopy (XPS). Enhancement in electrical conductivity due to Cu doping and IR illumination has been found. Band gap can also be tuned by varying doping concentrations. One new phenomenon called negative absorption (NA) has been found while investigating the optical properties in the infrared (IR) region for both undoped and Cu-doped NiO on the FTO substrate, which opens a new door for advanced research. The multifarious properties of NiO thin films offer various applications in many different fields.

The Near-Sightedness of Many-Body Interactions in Anharmonic Vibrational Couplings.

Couplings between vibrational motions are driven by electronic interactions, and these couplings carry special significance in vibrational energy transfer, multidimensional spectroscopy experiments, and simulations of vibrational spectra. In this investigation, the many-body contributions to these couplings are analyzed computationally in the context of clathrate-like alkali metal cation hydrates, including Cs+(H2O)20, Rb+(H2O)20, and K+(H2O)20, using both analytic and quantum-chemistry potential energy surfaces. Although the harmonic spectra and one-dimensional anharmonic spectra depend strongly on these many-body interactions, the mode-pair couplings were, perhaps surprisingly, found to be dominated by one-body effects, even in cases of couplings to low-frequency modes that involved the motion of multiple water molecules. The origin of this effect was traced mainly to geometric distortion within water monomers and cancellation of many-body effects in differential couplings, and the effect was also shown to be agnostic to the identity of the ion. These outcomes provide new understanding of vibrational couplings and suggest the possibility of improved computational methods for the simulation of infrared and Raman spectra.

Promoting Oxygen Evolution Electrocatalysis by Coordination Engineering in Cobalt Phosphate.

Understanding the structure-activity correlation is an important prerequisite for the rational design of high-efficiency electrocatalysts at the atomic level. However, the effect of coordination environment on electrocatalytic oxygen evolution reaction (OER) remains enigmatic. In this work, the regulation of proton transfer involved in water oxidation by coordination engineering based on Co3(PO4)2 and CoHPO4 is reported. The HPO4 2- anion has intermediate pKa value between Co(II)-H2O and Co(III)-H2O to be served as an appealing proton-coupled electron transfer (PCET) induction group. From theoretical calculations, the pH-dependent OER properties, deuterium kinetic isotope effects, operando electrochemical impedance spectroscopy (EIS) and Raman studies, the CoHPO4 catalyst beneficially reduces the energy barrier of proton hopping and modulates the formation energy of high-valent Co species, thereby enhancing OER activity. This work demonstrates a promising strategy that involves tuning the local coordination environment to optimize PCET steps and electrocatalytic activities for electrochemical applications. In addition, the designed system offers a motif to understand the structure-efficiency relationship from those amino-acid residue with proton buffer ability in natural photosynthesis.

A Sensitive Enzymatic Electrochemical Biosensor for Cholesterol Based on Cobalt Ferrite@Molybdenum Disulfide/Gold Nanoparticles.

Cholesterol is essential in biological systems, and the level of cholesterol in the body of a person acts as a diagnostic marker for a variety of diseases. So, in this work, we fabricated an enzymatic electrochemical biosensor for cholesterol using cobalt ferrite@molybdenum disulfide/gold nanoparticles (CoFe2O4@MoS2/Au). The synthesized composite was used for the determination of cholesterol by voltametric methods. The electroactive material CoFe2O4@MoS2/Au was successfully verified from the physiochemical studies such as XRD, Raman, FT-IR, and XPS spectroscopy along with morphological FESEM and HRTEM characterization. CoFe2O4@MoS2/Au showed outstanding dispersion in the aqueous phase, a large effective area, good biological compatibility, and superior electronic conductivity. The microflower-like CoFe2O4@MoS2/Au was confirmed by scanning electron microscopy. The image of transmission electron microscopy showed decoration of gold nanoparticles on CoFe2O4@MoS2 surfaces. Furthermore, a one-step dip-coating technique was used to build the biosensor used for cholesterol detection. In addition to acting as an enabling matrix to immobilize cholesterol oxidase (ChOx), CoFe2O4@MoS2/Au contributes to an increase in electrical conductivity. The differential pulse voltammetry method was used for the quantitative measurement of cholesterol. The calibration curve for cholesterol was linear in the concentration range of 5 to 100 μM, with a low limit of detection of 0.09 μM and sensitivity of 0.194 μA μM-1 cm-2. Furthermore, the biosensor demonstrates good practicability, as it was also employed for identifying cholesterol in real samples with acceptable selectivity and stability.