High-performance Coatings Research Articles

Imidazolium-Based Ionic Liquid Exhibiting Dual Hydrophilic and Oleophobic Properties without Polar End Groups.

Simultaneously hydrophilic and oleophobic surfaces offer substantial advantages for applications such as antifogging, self-cleaning, and oil-water separation. It remains challenging to engineer such surfaces without requiring polar functional groups. This study introduces HFIL, a novel ionic liquid (IL) coating that achieves simultaneous hydrophilic and oleophobic properties via a one-step dip-coating process without relying on polar functional groups. Key findings show that, despite the bulk form of HFIL having a high hexadecane contact angle (HCA) of 74.1° and an even higher water contact angle (WCA) of 87.6°, the IL forms a stable monolayer on high-energy surfaces exhibiting a much lower WCA of approximately 40° with minimal change to the HCA. Washing tests demonstrate that, even without the polar functional groups, there is a non-zero bonded thickness upon which the oleophobicity is comparable to polytetrafluorethylene (PTFE). These properties highlight HFIL's potential for durable applications in antifouling, antifogging, and environmental separation technologies, where selective liquid interactions are essential. This work contributes to a broader understanding of IL-based surface modifications, advancing the development of high-performance coatings.

High-Performance Multi-functional Solar Panel Coatings: Recent Advances, Challenges, Strategies and Industrial Aspects

Solar energy conversion is one of the most sustainable and cleanest methods of generating electricity to address the world's expanding energy needs. Solar cell panels, utilized in this conversion process,...

Kinetic and Thermodynamic Study of Ag+, Cu2+, and Zn2+ Ion Adsorption on LTA for High-Performance Antibacterial Coating

Antibacterial powder coatings have attracted increasing attention with the awakening of people’s health awareness. Silver antibacterial agent has been widely used in coating system due to its superior stability and durability. However, silver ions have the problems of excessive release rate and the tendency to cause yellowing of the coating film. The addition of Cu2+ and Zn2+ can effectively alleviate these two phenomena. In this paper, the ternary exchange kinetics of Ag+, Cu2+, and Zn2+ were studied to provide a theoretical basis for the synthesis of LTA-Ag-Cu-Zn. The reaction kinetics study shows that the selectivity and the adsorption capacity of LTA to Ag+ is higher than that of Cu2+ and Zn2+. The thermodynamic analysis discovers that LTA has the highest selectivity for Ag+, and the exchange between the two is spontaneous. In contrast, the selectivity of LTA to Cu2+ and Zn2+ is concentration-dependent. By establishing the three-ion competitive adsorption curve, it is found that the selectivity of Ag+ is the highest, and the selectivity of copper and zinc is similar. These trends result from Ag+ ions’ low hydration energy, small hydration radius, and strong electronegativity. This research lays the groundwork for developing high-performance LTA-Ag-Cu-Zn tri-ion exchange antibacterial agents.

Optimization of Process Parameters and Microstructure of CoCrFeNiTiAl High-Performance High-Entropy Alloy Coating

CoCrFeNiTiAl high-entropy alloy coatings have been prepared by laser cladding technology based on response surface methodology (RSM). The results show that the effects of laser power, cladding speed, and pulse width on the dilution rate and microhardness of the high-entropy alloy coatings are investigated. Among the single-factor results, the laser power has the most significant effect on the properties of high-entropy alloy coatings, followed by the cladding speed, while the pulse width has no significant effect. In the interaction term analysis, the interaction term of laser power and pulse width has a remarkable effect on both output responses, whereas the interaction term of pulse width and cladding speed only has a considerable effect on microhardness, while the interaction term of laser power and cladding speed has an insignificant effect on both output responses. The optimum parameters for the preparation of high-performance high-entropy alloy coatings are found at laser power P = 676.73 W, cladding speed V = 5 mm/s, and pulse width P0 = 9 ms. The microstructures of the high-entropy alloy coating prepared with optimal process parameters have been characterized, which show that the metallurgical bonding between the cladding layer and the substrate is strong and without obvious defects such as porosity and cracks.

Caramelization-inspired bio-based waterborne fire-resistant coating for various substrates

Inspired by the caramelization of sugar, which forms a viscous, nonflammable substance at around 150 °C, we developed a bio-based, intumescent fire-resistant coating. Comprising hydroxypropyltrimethyl ammonium chloride chitosan (HACC), phytic acid (PA), and magnesium gluconate (MgG), this coating underwent rapid dehydration and charring expansion upon exposure to fire at ca. 180 °C, expanding ∼137 times to create a protective honeycomb char layer that shields substrates from oxygen and heat. Importantly, this coating enhanced fire resistance for polypropylene (PP), rubber, polyurethane foam (PUF), wallpaper, and wood, while maintaining transparency and strong adhesion. Typically, the coating (200 μm) reduced the heat release rate of PP by 63.7 %, extending the time to ignition from 34 s to 525 s. Furthermore, the 1200 μm thick coating slowed the slow rise of backside temperature on thesteel plate, keeping it beneath 229 °C after being exposed to a butane torch flame at 1100 °C for 60 min. This eco-friendly innovation promises advanced fire protection and opens new avenues for sustainable, high-performance fire-resistance coatings.

Research on Ni-WC Coating and a Carbide Solidification Simulation Mechanism of PTAW on the Descaling Roll Surface

The descaling roll is a critical component in a hot-rolling production line. The operating conditions are significantly impacted by water with high-pressure and dynamic shocks caused by high-temperature steel slab descaling. Roll surfaces often experience wear and corrosion failures. This is attributed to a combination of high temperatures, intense wear, and repeated thermal, mechanical, and fluid stresses. Production costs and efficiency are significantly affected by the replacement of descaling rolls. Practice shows that the use of plasma cladding technology forms high-performance coatings. Conventional metal surface properties can be significantly improved. In this study, a Ni-WC composite coating was prepared on the descaling roll surface by plasma-transferred arc welding (PTAW) technology. The microstructure and phase composition of the welding overlay were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Results show that the WC hard phase added to the molten pool dissolves, and subsequently M7C3 and W2C phases are formed. To further explore the morphological evolution mechanism of the hard phase, numerical simulations were performed using a phase-field method to model M7C3 phase precipitation. The evolution from nucleation, rod-like growth, to eutectic structure formation was revealed. Experimental and simulation results show high consistency, validating the established phase-field model. In this study, a theoretical foundation for designing and preparing high-performance coatings is provided.

The effects of current density on the properties of HAp-Nb2O5 films electrodeposited by pulsed current

ABSTRACT The performance of electrodeposited coatings is usually very dependent on the operating conditions. Current density can have a major effect on the appearance of electrodeposits, their physical/mechanical properties and corrosion resistance. In the present study, HAp-Nb2O5 composite layers were electrodeposited on NiTi from stirred, aqueous electrolytes, containing 1 g dm−3 of suspended Nb2O5 particles at a current density of 10, 15 or 20 mA cm−2. The morphology, topography, and elemental composition of the surface were determined using FESEM, AFM, and EDS, respectively. A higher current density enhanced the content of co-deposited Nb2O5 particles but risked the formation of particle aggregation. Microhardness and corrosion, carried out by the Vickers microhardness and potentiodynamic polarization techniques, illustrated that the films electroplated at 15 mA cm−2 showed the highest corrosion resistance performance and the least Ni2+ ion leaching. The results may aid the development of high-performance coatings on NiTi in orthopaedic applications..

One stone three birds: Multifunctional epoxy composites based on rice-granular nickel/iron bimetallic phyllosilicates enable excellent compression, anti-wear and lubricating properties under wet-sliding conditions

Epoxy resin (EP) is a versatile thermoset resin extensively employed as protective coatings. However, its brittleness causes poor wear resistance and presents a significant challenge in the application under harsh environmental circumstances. The preparation of EP composites by rationally selecting functional inorganic fillers offers a promising strategy for enhancing mechanical and tribological properties. In this paper, multifunctional EP composites were successfully fabricated with varying mass fractions of rice-granular nickel/iron bimetallic phyllosilicate (NiFePS). The compressive properties, water contact angles, wet-sliding responses, and the morphological analysis of worn surfaces for EP composites were carried out and discussed in detail. Results indicate that the incorporated NiFePS scarcely alters the compressive stress-strain curves, still exhibiting the representative stages including elastic transformation, stress yielding and strain hardening throughout the entire compressive process. The compressive strength, elastic modulus and fracture energy initially increase and then decrease, attaining the maximum values of 266.3 MPa, 4.43 GPa, and 72.1 J/cm², respectively, with the addition of merely 1 % NiFePS. Furthermore, the introduction of NiFePS significantly reduces the water contact angle, transforming the surface of EP composite from hydrophobic to hydrophilic. The friction coefficient and wear rate of EP composites decrease sharply with the addition of NiFePS, achieving the lowest values of 0.136 and 1.24×10⁻⁶ mm³/Nm simultaneously at a filler concentration of 1 %, which represent reductions of 17.07 % and 70.55 %, respectively, compared to the resin matrix. Additionally, the wet-sliding responses affected by various applied loads, rotating speeds and abrasive durations are comprehensively discussed. Finally, the wear mechanism of EP composites is elucidated through in-depth examinations of the evolving morphologies and chemical compositions of the worn surfaces. This work presents a feasible three-in-one technology for developing multifunctional materials with significant potential in high-performance composites and coatings.

Near-Infrared-Induced High-Performance Antimicrobial Active Coating for Medical Textiles Based on Easy-to-Synthesize Natural Catechin with Full End of Life Circularity

Near-Infrared-Induced High-Performance Antimicrobial Active Coating for Medical Textiles Based on Easy-to-Synthesize Natural Catechin with Full End of Life Circularity

A universal strategy to design recyclable photocrosslinked networks via architecting lignin-derived spiro diacetal trigger

Precise transformation of renewable resources into high-performance photo-crosslinked resins with degradability remains a daunting challenge. In this work, we employed a renewable bioresource, lignin-derived vanillin, to construct a rigid spiro diacetal trigger, which was further coupled with thermosetting epoxy segments to develop three high-performance functionalized polymers. Several high-performance photosensitive materials with alkali-dissolving patterning and recyclable were innovatively engineered based on these polymers. The introduction of rigid spiro diacetal triggers, which function through a unique degradable mechanism under mildly acidic conditions, is expected to address the “seesaw” issue between high performance and degradability in photo-crosslinked networks. More importantly, the effect of spiro diacetal trigger on the thermo-mechanical properties and photopolymerization kinetics of thus-obtained photosensitive resins was systematically investigated. Consequently, the glass transition temperature and mechanical properties of the spiro diacetal-tailored naphthalene-type photosensitive resin (P-VPNE) are comparable to, or even exceed, those of competing materials. This work provides a universal strategy and valuable insights for the design and synthesis of high-performance degradable electronic packaging coatings, which are essential for a wide range of revolutionary technologies based on lignin derivatives.

Wear behaviour of ceramic coating (Al2O3-40%TiO2) in dry condition for automotive applications

The objective of the current research is to examine the effect of varying loads on the wear behaviour of Al2O3-40%TiO2 ceramic coating deposited by flame spray process and to improve material functionality and increase lifecycle in a cost-effective method. To assess the wear behaviour of the deposition, wear test was conducted using a Pin-on-disk tribometer in accordance with ASTM G99 standards. This test was designed to analyse the wear experienced by the coating in practical applications. Surface morphology was examined using field emission scanning electron microscope (FESEM) and energy dispersion spectroscopy (EDS) technique while 3D-profilometer was utilised to further assess the surface roughness of the deposited coating. It was observed that specific wear rate of the deposition exhibited a decreasing trend with increasing load from 40 to 70 N and sliding velocity from 0.4 to 1 m/s. The lowest coefficient of friction was observed at 70 N and 1 m/s. Wear mechanism analysis revealed different types of wear, including abrasion, metal transfer, and brittle fracture, corresponding to the increasing load and sliding velocity. This study is significant for industries that require high-performance coatings for industries such as automotive, aerospace and manufacturing, where high-performance coatings are needed to withstand heavy loads and friction. The current research findings enhance wear resistance and reduce friction, helps manufacturers to adapt coating for specific operational requirements.

Preparation of ester-modified nano-SiO2/silicate coatings and its application in the impermeability of concrete

Surface treatment protective technology is a cost-effective approach to prevent harmful ions from infiltrating concrete, avoiding the deterioration of performance and increasing longevity. Here, a novel coupling agent with ester group (MA-KH-550) is synthesized from γ-aminopropyltriethoxysilane (KH-550) and methyl acrylate (MA) to modify nano-SiO2 particles. Subsequently, the ester-modified nano-SiO2 can be successfully dispersed in alkaline composite silicate solutions to fabricate nano-SiO2/silicate coatings, improving the impermeability of concrete. The incorporation of nano-SiO2 particles can fill microscopic pores in cementitious materials, which improves the compactness of the concrete. Furthermore, nano-SiO2 particles can also accelerate secondary hydration of cement and synergistically generate more calcium silicate hydrate gel with silicates to further boost the compactness of the concrete. High-compactness coatings reduce the penetration of the medium, thereby enhancing the impermeability performance of the concrete. When the nano-SiO2 particle content is 1.0 wt%, the optimal performance of concrete is achieved. Compared with the original C30 concrete, the C30 concrete treated with the nano-SiO2/composite silicate (nano-SiO2/CSC) shows a 31.1 % decrease in chloride ion resistance, a 35.5 % reduction in carbonization resistance, a loss rate of 1.08 % for anti-freezing quality. This work charts a new course for designing and developing high-performance composite silicate coatings for concrete.

Microstructure evolution and properties of (Nb,M)C (M=Ti,V and Zr) reinforced Ni-WC coatings by laser cladding

To enhance the surface properties of AISI 1045 steel, high-performance composite carbide-reinforced coatings were prepared using laser cladding technology. Specifically, (Nb,M)C (M = Ti, V, and Zr) reinforced Ni-WC coatings were developed. The effects of various composite carbides on the microstructure and properties of the coatings were examined through a combination of first-principles calculations and experimental methods. Initially, the microstructures of (Nb,M)C (M = Ti, V, and Zr) were constructed using first-principles calculations, and the microscopic mechanical and electronic properties of these composite carbides were determined. The impact of different doping elements on the properties of the composite carbides was investigated. Subsequently, an in-situ synthesis system was designed to fabricate the composite coatings. The feasibility of synthesizing the composite carbides (Nb,M)C (M = Ti, V, and Zr) within the laser cladding coatings was confirmed using XRD, SEM, and EDS techniques. Additionally, the formation mechanism of the composite carbides was analyzed. Under different element doping conditions, the reinforcement phase in the composite coating exhibited various grain morphologies, with (Nb0.5Ti0.5)C grains showing the best particle size and density. Microalloyed interfaces were observed at the WC interfaces in each coating, indicating strong bonding between WC and the FCC matrix. The presence of WC also improved the fineness of the surrounding phase structure. Due to differences in kinetics and thermodynamics, a core-shell structure of (Nb0.5Ti0.5)C-core and WpC-shell was observed in the (Nb0.5Ti0.5)C coating. Friction-wear tests revealed that this core-shell structure helps alleviate crack sensitivity between the reinforcing phase and the matrix. Hardness analysis showed that the average hardness of the (Nb0.5Ti0.5)C, (Nb0.5V0.5)C, and (Nb0.5Zr0.5)C coatings was 62.89 HRC, 60.91 HRC, and 58.27 HRC, respectively. Among these, (Nb0.5Ti0.5)C demonstrated the most significant hardness enhancement for AISI 1045 steel, achieving a 3.51-fold increase. In the friction and wear tests, the (Nb0.5Ti0.5)C coating exhibited the best wear resistance. The primary friction-wear mechanisms of the coatings were found to be adhesive wear, oxidative wear, and minor abrasive wear. These research findings provide a theoretical basis for the preparation of high-performance composite carbide-reinforced coatings using laser cladding.

Impressive reinforcement on the anti-corrosion ability of the commercial fluorocarbon paint via an amino groups modified graphene

The interaction with the matrix and the dispersion within the matrix hinder the realization of graphene's potential as an anti-corrosive filler. Herein, a -NH2 modified graphene-based filler (PS-PVP@NH2-rGO) was designed to simultaneously address these issues in the fluorocarbon resin (FEVE) coating. Reinforing FEVE coating with PS-PVP@NH2-rGO, the wear rate and the lowest-frequency impedance modulus after a 7-day immersion were found to be 0.35 times and 177.3 times those of FEVE coating respectively. Ultraviolet-Visible spectra confirmed the excellent dispersibility of PS-PVP@NH2-rGO. The designed differential scanning calorimeter experiment demonstrated the close interaction between PS-PVP@NH2-rGO and the FEVE matrix. Due to this close interaction, PS-PVP@NH2-rGO exhibited a high degree of dispersion within the FEVE matrix rather than self-aggregation, then concentrated the stress outside, absorbed energy produced during the friction process, and enhanced the coating's wear resistance. A complicated “labyrinth” was also created by the fillers. With chemical interactions, the fillers and the surrounding FEVE matrix formed an integrated whole, making the “obstacles” created by the fillers more significant. Consequently, the strong barrier effect resulted in superior anti-corrosion performances of PS-PVP@NH2-rGO/FEVE coating. Introducing -NH2 groups in was proven to effectively complete the coating, improve coating's quality and barrier effect, and finally prevent corrosive media. This study aims to provide design ideas and theoretical supports for high-performance heavy-duty anti-corrosive coatings.

Fractionation of Kraft Lignin for Production of Alkyd Resins for Biobased Coatings with Oxidized Lignin Dispersants as a Co-Product.

A new valorization pathway based on solvent fractionation was applied to kraft lignin, a major by-stream of the pulping industry, to extract a soluble lignin intermediate featuring an improved structural homogeneity, a low molecular weight, and a high content of phenolic hydroxyl and carboxylic acid groups to serve as a substitute of the nonrenewable polyacids in the formulation of alkyd resins, a dominant material used in the production of anticorrosion surface coatings. Herein, softwood kraft lignin was mixed in a low-cost green solvent, aqueous ethanol, prepared at different ratios, at room temperature to generate a soluble fraction of a low M w of ≤2200 g mol-1 and an insoluble fraction of a high M w of ≥3950 g mol-1 of lignin. The best combination of yields and molecular weights of soluble lignin (16-36% yield, 1740-1890 g mol-1) was attained using 50-80 vol % ethanol in fractionation. Thus, these conditions were further employed at the pilot scale to demonstrate the scalability of this technology. Soluble lignin from pilot fractionation was used to produce an optimal alkyd resin formulation and thereafter an anticorrosion coating on the metal surface, both of which matched the target properties of industrial standards well (180 s Persoz hardness and 72 gloss units of coating, 100% adhesion of paint with no cracks or peeling in the cross-cut test, no corrosion after 120 h of the salt spray test). The insoluble solids from pilot fractionation could also be valorized by alkali-O2 oxidation into lignin-based dispersants for special carbon black pigments. Overall, this study presents a new, simple strategy to develop an efficient, scalable, low-cost, and green process for upgrading kraft lignin into phenolic intermediates for biobased alkyd resins to facilitate sustainable production of high-performance anticorrosion coatings.

Mussel-Inspired, Self-Healing, Highly Effective Fully Polymeric Fire-Retardant Coatings Enabled by Group Synergy.

Fire-retardant coatings represent a universal cost-effective approach to providing fire protection for various substrates without compromising substrates' bulk properties. However, it has been attractive yet highly challenging to create waterborne polymeric fire-retardant coatings combining high-efficiency, generally strong adhesion, and self-repairability due to a lack of rational design principles. Inspired by mussel's unique adhesive, self-healing, and char-forming mechanisms, herein, a "group synergy" design strategy is proposed to realize the combination of self-healing, strong adhesion, and high efficiency in a fully polymeric fire-retardant coating via multiple synergies between catechol, phosphonic, and hydroxyethyl groups. As-created fire-retardant coating exhibits a rapid room-temperature self-healing ability and strong adhesion to (non)polar substrates due to multiple dynamic non-covalent interactions enabled by these groups. Because these functional groups enable the formation of a robust structurally intact yet slightly expanded char layer upon exposure to flame, a 200µm-thick such coating can make extremely flammable polystyrene foam very difficult to ignite and self-extinguishing, which far outperforms previous strategies. Moreover, this coating can provide universal exceptional fire protection for a variety of substrates from polymer foams, and timber, to fabric and steel. This work presents a promising material design principle to create next-generation sustainable high-performance fire-retardant coatings for general fire protection.

Ablation-resistant yttrium-modified high-entropy refractory metal silicide (NbMoTaW)Si2 coating for oxidizing environments up to 2100 °C

Refractory high-entropy alloys (RHEAs) are pivotal in ultra-high temperature applications, such as rocket nozzles, aerospace engines, and leading edges of hypersonic vehicles due to their exceptional mechanical ability to withstand severe thermal environments (in excess of 2000 °C). However, the selection of materials that satisfy the stringent criteria required for effective ablation resistance remains notably restricted. Here, a novel yttrium-modified high-entropy refractory metal silicide (Y-HERMS) coated on a refractory high-entropy NbMoTaW alloy is developed via pack cementation process. The developed Y-HERMS coating with sluggish diffusion effect demonstrates extraordinary ablation resistance, maintaining near-zero damage at sustained temperatures up to 2100 °C for a duration of 180 s, surpassing state-of-the-art high-performance silicide coatings. Such exceptional ultra-high ablation performance is primarily ascribed to the in-situ development of a high viscosity Si-Y-O oxide layer with increased thermal stability and the presence of high-melting Y(Nb0.5Ta0.5)O4 oxides as skeleton structure. Theoretical results elucidate that the Y-HERMS promotes the formation of SiO2, which impedes the diffusion of O into metal silicide layer, synergistically contributing to the superior ablation resistance. These findings highlight the potential of utilizing high-entropy materials with excellent ablation resistance in extreme thermal environments.

Enhanced thermal performance of CeYSZ coating on Ni-based high temperature alloy with a unique Y-doped Al2O3 barrier layer via cathodic plasma electrolytic deposition

Cathodic plasma electrolytic deposition (CPED) has shown considerable potential in producing high-performance thermal barrier coatings (TBCs) for components operating in extreme thermal environments, such as gas turbines and aviation engines. However, the dendritic and porous structures greatly limited the use of CPED-coatings in some harsh environments. In this study, one Y-doped Al2O3 (Y/A) barrier layer was prefabricated before the deposition of CeO2 and Y2O3 stabilized ZrO2 (CeYSZ) TBCs using CPED. The results suggested that the prefabricated Y/A barrier layer could attenuate the plasma bombardment and promote the uniform discharge, resulting in the formation of a thinner gas film on the cathode surface, which significantly avoided the dendritic defects and improved the density of the CeYSZ coating from 6.788 g/cm³ to 6.978 g/cm³. Consequently, the thermal insulation temperature of Y/A-CeYSZ coatings increased by 83.7% than that of CeYSZ coating, and the thermal cycling performance at 1300 °C demonstrated a 52.5 % improvement. This study provided a valuable method for the development of novel CPED TBCs.

Preparation and performances of conductive, wear-resistant, and anti-corrosion coatings based on low content monodisperse SWCNTs

Single-walled carbon nanotubes (SWCNTs) are considered an ideal candidate material for multifunctional coatings because of their excellent electrical, thermal and mechanical properties. However, achieving uniform dispersion of SWCNTs while maintaining their structure and performance remains a significant challenge. The monodisperse SWCNTs (m-SWCNTs) can be obtained using a non-covalent PVP dispersant under the graded homogenization method. PVP acted as steric hindrance due to the π-π conjugate, thereby hindering the agglomeration and preventing the damage of SWCNTs. We incorporate low amounts of m-SWCNTs into fluorocarbon (FC) coatings to fabricate m-SWCNTs/FC composite coatings. We also investigate the effect of m-SWCNTs content on the electrical conductivity, corrosion resistance and wear resistance of the composite coating. Our results indicate that when the content of m-SWCNTs reaches at 0.25 wt%, the electrical resistivity of the m-SWCNTs/FC composite coating is 1.67 × 10−2 Ωm, significantly decreased by 9 orders of magnitude compared to FC coating. The conductive network would be formed by the high aspect ratio and non-damaged of m-SWCNTs to improve the conductivity. Additionally, the wear rate containing 0.15 wt% m-SWCNTs decreased by 50.1 % due to the improved strength and heat conduction to inhibit the adhesive wear. Furthermore, in comparison to bare steel, the corrosion current density of 0.15 wt% m-SWCNTs/FC composite coating is reduced by two orders of magnitude due to zigzag the corrosive path. Our studies suggest that the m-SWCNTs/FC composite coatings have a broad prospect in preparing large-scale, high-performance, and low-cost functional coatings.

A Comprehensive Review on the Tribological Evaluation of Polyether Ether Ketone Pristine and Composite Coatings.

Polymer coatings have gained a lot of attention in the recent past because of their ability to be easily coated on complex shapes, their low cost, and their ability to reduce friction as compared to other materials. Polyether ether ketone (PEEK) is one such high-performance polymer that has gained significant attention in recent years due to its exceptional mechanical properties, chemical resistance, and thermal stability making it a prominent candidate for applications in industries. However, PEEK in its pristine form exhibits poor wear resistance with a moderate coefficient of friction (0.30-0.38). Many attempts have been made by several researchers to improve its wear resistance and lower the COF by developing composite coatings. Hence, in this review, we aim to summarize and present in detail the tribological evaluation of pristine PEEK and PEEK composite coatings by discussing the various methods adopted by the researchers to improve the properties of PEEK, the different types of reinforcements and various dispersion techniques used to develop PEEK composite coatings. By consolidating and analyzing the existing body of knowledge, we also aim to offer valuable insights into the development of more durable, high-performance PEEK nanocomposite coatings for a broad range of tribological applications.