Effect Of Mn Doping Research Articles

Insights into the Mn-doping effects on the catalytic performance of ZnCrAlOy/SAPO-34 bifunctional catalyst for the direct conversion of syngas to light olefins

Direct conversion of syngas to light olefins (C2=-C4=) over oxide-zeolite bifunctional catalyst provides a new strategy for light olefins production. Herein, we report a series of bifunctional catalysts composed of SAPO-34 zeolite and Mn-doped ZnCrAlOy oxide with the Mn/Cr ratio ranging from 0 to 0.3 for directing conversion of syngas to light olefins. We achieved a C2=-C4= selectivity of 78.60% (free of CO2) in all hydrocarbon products with a CO conversion of 23.53% and STY of 0.19 g/h·gcat. No obvious deactivation was observed after 220 h reaction. The impact of Mn doping on the physicochemical properties of ZnCrAlOy spinel oxides was explored by various in-situ and ex-situ characterizations. It was found that the Mn doping could decrease the particle size of ZnCrAlOy spinel, which leads to the formation of more oxygen vacancies on the surface of catalyst. The oxygen vacancies (Odef/Olatt) were increased from 0.34 to 0.41 when the Mn content ranges from 0 to 0.2. The abundant oxygen vacancies are beneficial to protect more light olefins and intermediate from hydrogenation. These findings are significant for the further development of high-efficiency bifunctional catalysts for the conversion of syngas to hydrocarbons.

Effects of Mn doping on structural properties and conduction mechanism of NaCu0.2Fe0.8−xMnxO2 (x = 0.4; 0.5; 0.6; 0.7) materials

The NaCu0.2Fe0.8−xMnxO2 (x = 0.4; 0.5; 0.6; 0.7) samples were synthesized using conventional solid states method. Analyzing the DXR measurement through the use of FullProf allowed us to prove the purity of these samples and to corroborate that they crystallize in hexagonal system in the R-3 m space group. The refinement of the crystalline structure revealed the O3 structure type for compounds whose x = 0.4 and x = 0.5 and the P3 structure type for compounds whose x = 0.6 and x = 0.7. It is to be noted that the impedance spectroscopy results expressed in terms of a Nyquist diagram demonstrated three contributions which are grain, grain boundary and electrode effects. The conduction mechanism deduced from the study of ac conductivity goes in good agreement with the overlapping large polaron (OLPT) to compounds whose x = 0.4 and 0.5. However, for the sample whose x = 0.6 and 0.7, the conduction process was determined through the correlated barrier hopping (CBH) model. Furthermore, we examined the influence of Mn substitution on structural and electrical properties. Therefore, by increasing the Mn amount, we inferred that the structure changed from O3 to P3, which affected the electrical properties and enhanced the grain conductivity owing to the decreasing volume of the sodium site.

Unravelling the nature of the active species as well as the Mn doping effect over gamma-Al2O3 catalyst for eliminating AsH3 and PH3

To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH3 and PH3 by CuO-Al2O3 in a reducing atmosphere under micro-oxygen conditions, Cu-Mn modified γ-Al2O3 catalysts were prepared. The characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component, increased the number of oxygen vacancies and acidic sites on the catalyst surface, enhanced the mobility of surface oxygen, and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance, which increased the conversion frequency (TOF) by 2.54 × 10−2 to 3.07 × 10−2 sec−1. On the other hand, the introduction of Mn reduced the production of phosphate and As2O3 on the catalyst surface by 30.96% and 44.9%, which reduced the coverage and inerting of the active sites by phosphate and As2O3, resulting in an 8 hr (6 hr) improvement in the stability of PH3 (AsH3) removal.

Spray Synthesized Mn‐doped CuO Electrodes for High Performance Supercapacitor

AbstractA pristine copper oxide and manganese‐doped copper oxide nanostructured films were prepared by simple spray pyrolysis technique. A study of the effects of Mn doping with three different concentrations as 2, 4, and 6 wt % were studied in the view of enhancement of supercapacitive performance of copper oxide electrode. The 6 wt % manganese‐doped copper oxide thin film changed their surface morphology considerably favorable to the exchange of ions in the Na2SO4 electrolyte. The electrochemical properties of the pristine copper oxide and manganese‐doped copper oxide were investigated in 1 M Na2SO4 electrolyte within the potential window of −1.0 to 0.4 V. A maximum specific capacitance of 801.61 F/g was obtained for the manganese‐doped copper oxide thin film electrode.

Effect of Mn doping on the structural, spectral, electrical, ferromagnetic and piezoelectric properties of 0.7BFO-0.3BTO lead-free ceramics

Lead-free 0.7BiFeO 3 -0.3BaTi 1−x Mn x O 3 ceramics, where x ranges from 1% -- 10%, were prepared by conventional solid state reaction method. Effect of addition of MnO 2 on the structural, spectral, electrical, magnetic and piezoelectric properties of 0.7BiFeO 3 -0.3BaTiO 3 material were studied systematically. The previous studies have emphasized on the doping in BiFeO 3 rather than doping in BaTiO 3 in BiFeO 3 -BaTiO 3 system. Our work focuses on the influence of Mn doping in BaTiO 3 in the BiFeO 3 -BaTiO 3 system. All the ceramics were calcined at the optimum temperature of 800 °C to minimize the impurity phases to a great extent. The synthesized ceramics have a co-existence of R and T phases with a space group of R 3 c and P 4 mm respectively with a small amount of Bi 25 FeO 40 impurity. The sample for x = 0.01 has R as the host phase rather than T phase, but as the concentration of Mn increases to 0.10, the R phase and T phase start forming a more stable solid solution. Additionally, the doping effect of Mn on grain and grain boundary was studied at 300 °C and illustrated by their equivalent circuits with the help of ZView 2 software. The grain resistance decreased significantly for the sample with x = 0.10. Hence, the addition of MnO 2 significantly enhanced the electrical and piezoelectric properties of the 0.7BiFeO 3 -0.3BaTiO 3 material. The improved electrical properties at high temperature and low frequencies ε r = 1.8 × 10 9 , σ = 4.1 × 10 −3 S cm −1 and piezoelectric property d 33 = 128 pC/N was obtained for x = 0.10. • XRD revealed that all the synthesized ceramics exhibit a perovskite R and T phases confirming the formation of a stable solid solution. • High dielectric constant which increases with increasing temperatures with high Curie temperature (above 500 °C). • Both grain and grain boundary contributed to electrical conductivity. • The high electrical resistivity was achieved at lower temperature which varies with the dopant concentration. • The maximum phase angle of 89.82° was achieved at 100 °C for a ceramic with highest dopant concentration. • The high d 33 value of 128 pC/ N was obtained for almost all the ceramics.

Photocatalytic and antimicrobial activities of pure and Mn doped ZnO nanoparticles synthesised by Annona Muricata leaf extract

ABSTRACT The present work aim to investigate the photocatalytic, antibacterial and antifungal activities of Zn1-xMnxO (x = 0.0, 0.03, 0.05 and 0.07) nanoparticles synthesised using the leaf extract of Annona Muricata via green synthesis method. The effect of Mn doping in the obtained nanopowder were studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), high-resolution transmission electron microscopy (HRTEM), selected area diffraction pattern (SAED), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and UV-visible spectroscopy techniques. XRD pattern confirms hexagonal wurtzite structure of ZnO nanoparticles. Incorporation of Mn into the ZnO host lattice was confirmed by XPS measurement. Morphology of nanoparticles shows irregular, spherical shapes with agglomeration. Presence of Zn, Mn and O elements in the EDAX reveals the perfect nature of nanostructures. The synthesised pure and Mn-doped ZnO nanoparticles were found to be significant antibacterial activity against gram positive Bacillus subtilis, Staphylococcus aureus and gram negative Pseudomonas aeruginosa bacterial pathogens as well as the fungal strain of Candida albicans and Aspergillus Niger. The minimum zone of inhibition observed for bacterial and fungal pathogens confirms better antimicrobial activity of ZnO nanoparticles. The Mn-doped nanoparticle shows comparatively enhanced removal of methylene blue (MB), malachite green (MG) and Congo red (CR) dye under sunlight. These results indicates the green synthesised pure and Mn-doped ZnO nanoparticles have valuable applications in environmental and biomedical fields.

Elucidation of synergistic effect of Mg-co-doping on electrochemical performance of Mn-doped LiNiO2

• The Li + /Ni 2+ cation mixing can be reduced by Mg co-doping. • The Mg co-doping may suppress the alteration of the lattice volume. • The Mg co-doping has a negligible effect on the interfacial property. • The superior performance of material is further gained via Mg co-doping. • The Mg-Mn co-doping has synergistic effects on stabilizing the LiNiO 2 material. Element doping is one of the most efficient strategies to boost the stability and performance of LiNiO 2 -based materials, to obtain a thorough understanding of the role of element doping. Particularly, the synergistic effect of the co-doped elements will be crucial for the design of the materials. Herein, we synthesize a series of Mg incorporated LiNiO 2 with a fixed Mn-doping content to better understand the synergistic effect of Mg co-doping. It is demonstrated that the incorporation of the Mg 2+ ions in the Li slabs leads to suppression of the Li + /Ni 2+ mixing and decreases the crystal lattice volume change during lithiation/delithiation processes. Therefore, the electrochemical stability of the material can be further enhanced, in addition to the stabilization effect of Mn-doping. The capacity retention of LiNiO 2 doped with 4 mol% Mn and 0.3 mol% Mg (LiNi 0.957 Mn 0.04 Mg 0.003 O 2 ) is 88.26 % after 200 cycles at 0.5C. This is also highlighted by the improved capacity retention at 4.6 V upper cutoff voltage. Moreover, due to the “pillar effect” of the co-doped Mg 2+ ions in the Li slabs, the material exhibits superior rate capability. The findings may be beneficial for the development of Co-free nickel-rich materials for the lithium-ion batteries.

The effect of Mn-doping on dielectric properties of titanate nanowires

Mn-doped titanate nanowires (TNWs) with system of MnxTi3-xO7 (Na0.96H1.04∙3.42H2O) (where x = 0, 0.05, 0.10, 0.20, and 0.30) were fabricated a hydrothermal route at 130 °C for 24 h. The products were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-vis spectroscopy. The nanowires were an average diameter of about 10–50 nm and an average range length of micrometer scales. The dielectric relaxation in the MnxTi3-xO7 (Na0.96H1.04∙3.42H2O) system was determined by LCR Meter in difference frequency (102–106 Hz) at various temperatures. The Mn-doped TNWs samples showed a giant dielectric exhibit with a dielectric constant of about 104 at 30 °C and 1 kHz. They all have a Debye-like relaxation based on the Maxwell-Wagner polarization. The dielectric constant of Mn-doped TNWs significantly increased with increasing doping levels.

Facile preparation and efficient MnxCoy porous nanosheets for the sustainable catalytic process of soot

The pursuit of high-performance is worth considerable effort in catalysis for energy efficiency and environmental sustainability. To develop redox catalysts with superior performance for soot combustion, a series of MnxCoy oxides were synthesized using MgO template substitution. This method greatly improves the preparation and catalytic efficiency and is more in line with the current theme of green catalysts and sustainable development. The resulting Mn1Co2.3 has a strong activation capability of gaseous oxygen due to a high concentration of Co3+ and Mn3+. The Mn doping enhanced the intrinsic activity by prompting oxygen vacancy formation and gaseous oxygen adsorption. The nanosheet morphology with abundant mesoporous significantly increased the solid–solid contact efficiency and improved the adsorption capability of gaseous reactants. The novel design of Mn1Co2.3 oxide enhanced its catalytic performance through a synergistic effect of Mn doping and the porous nanosheet morphology, showing significant potential for the preparation of high-performance soot combustion catalysts.

Synergistic effect of Mn doping and hollow structure boosting Mn-CoP/Co2P nanotubes as efficient bifunctional electrocatalyst for overall water splitting

The sluggish kinetic of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) severely hampers the commercial application of electrochemical water splitting, promoting the urgent exploration of high-efficient bifunctional electrocatalysts. Heteroatom doping and structure engineering have been identified as the most effective strategies to boost the catalytic activity of electrocatalysts. Herein, Mn doping and hollow structure were integrated in the design of Co-based transition metal phosphide catalyst to prepare Mn-CoP/Co2P nanotubes (denoted as Mn-CP NTs) by a facile template-free method. Confirmed by characterization analysis, the introduced Mn species were in high dispersion in the regular CoP/Co2P hollow tubular framework. Such a favorable design in composition and structure effectively boosted the catalytic activity of Mn-CP NTs toward electrochemical water splitting. The Mn-CP NTs showed superior HER and OER activity demonstrated by the low overpotentials of 82 mV (vs HER) and 309 mV (vs OER) at the current density of 10 mA cm−2, as well as the satisfactory durability. When used as both cathode and anode in electrolyzer for overall water splitting, only a low cell voltage of 1.67 V was required for the Mn-CP NTs to drive 10 mA cm−2, accompanied with excellent stability confirmed by over 50 h test.

Ethanol gas sensing performance of spinel Mn: Co3O4 nanostructure thin film prepared by spray pyrolysis

In this present, the effect of Mn doping was investigated on the structural, surface morphology, and optical properties of Co3O4 and Mn: Co3O4 thin films prepared by spray pyrolysis on a glass substrate. X-ray diffraction patterns of these films show the spinel cubic structure with no secondary phases corresponding to the impurity or other Mn oxides. The grain size of these electrodes was determined about 25 nm. Scanning electron microscopy images show that the Mn changed the Co3O4 surface structure. The optical property was studied by UV–vis spectroscopy in 400–1100 nm and the band gap was determined by two different methods. The UV–vis spectra shows the Mn: Co3O4 thin films have two absorption edges with two direct and indirect band gaps at ∼2.2 and 1.5 eV. The energy dispersive spectroscopy (EDS) analysis confirmed that the Mn doping has been done successfully. The resistance of films was measured at about 103 Ω/□, and decreased by increasing Mn concentration. Then the characteristics of the Mn: Co3O4 gas sensors such as sensitivity, response time, recovery time, and operating temperature were investigated under 100 ppm ethanol as a reducing gas. The operation temperature in this research was 250 C. The response time and operating temperature were investigated under 100 ppm ethanol.

Effect of Mn Doping on the Optical and Electrical Properties of Double Perovskite Sr2TiCoO6.

A new series of Sr2TiCo1−xMnxO6 (0.0 ≤ x ≤ 0.7) materials has been synthesized using the conventional solid-state method. In this research, X-ray diffraction (XRD) results showed that Mn was successfully doped at the Co site in a cubic structure with monoclinic P21/n space group. The effect of Mn cation substitution on the structural, optical and electrical performance of Sr2TiCo1−xMnxO6 double perovskite was investigated. The optical study revealed a nonlinearity pattern of the band gap that is referred to as the band gap bowing trend. Results from optical and Rietveld refinement supports that the band gap bowing trend is correlated with the charge distribution that produces unique effects on structural and size changes due to the Co-Mn compositions. The morphological scanning electron microscopy studies also showed that larger crystallite sizes were developed when dopant was added. Furthermore, increases in the conductivities support the lowering band gap of Mn-doped samples. Here, the intermixing of the atomic orbitals of Co-Mn provides an efficient interlink electrical pathway to improve conductivity and exhibits a high dielectric property at room temperature. These values are strong evidence that STCM material will be suitable for applications in the semiconductor industry.

Surfactant assisted synthesis of nanostructured Mn-doped CuO: An efficient photocatalyst for environmental remediation

The nanostructured Mn-doped CuO material was hydrothermally synthesized using urea as a surfactant to control the shape and size of the material particles. Advanced physiochemical methods were used to look at the microstructure, texture, morphology, and chemistry of the Mn-doped and pristine CuO materials. I–V and UV/visible experiments were performed on doped and un-doped materials to investigate the effect of Mn-doping on electrical conductivity and bandgap. The antibacterial and photocatalytic characteristics of the hydrothermally prepared materials were evaluated and compared through the destruction of Escherichia coli (E.coli) and the photocatalytic mineralization of Rh–B dye. The Mn-doped CuO material has much better photocatalytic activity for the mineralization of Rh–B dye than pristine CuO, with 93.8% dye mineralization after 90 min of visible light illumination compared to 56.52% for pristine CuO. The Mn-doped CuO material mineralized the Rh–B dye at a rate constant (k) of 0.02152 min−1, about three times faster than virgin CuO (k = 0.00802 min−1). The Mn-doped CuO material has negligible electron-hole recombination aptitude but quicker charge transport characteristics than the un-doped comparable based on transient photocurrent and impedance testing. The current work shows how to make a doped semiconductive material that can be used to clean up the environment and is versatile, cheap, and very effective.

Effect of Mn-doping on the morphological and electrical properties of (Ba0·7Sr0.3) (MnxTi1−x)O3 materials for energy storage application

Lead-free (Ba0·7Sr0.3) (MnxTi1−x)O3 (x = 0.0, 1.0, 2.0, 4.0, 6.0, and 8.0%) ceramics were effectively synthesized by the sol-gel process. XRD and Raman spectroscopy confirm the single-phase perovskite structure with tetragonal symmetry, for all compositions. An in-depth analysis of the chemical composition and thermochemistry of the ceramics was carried out via FT-IR and TG-DTG. Morphological analyses of the samples revealed that doping Mn at higher concentrations suppresses the grain size and grain growth rate. The dielectric properties increased first and then decreased with increasing Mn content. The ferroelectric properties represented similar trend in polarization and energy storage efficiency as showed in dielectric properties. 2% Mn-doped sample exhibits the best dielectric and energy storage performance which is attributed to increased densification and grain size effects. Dielectric anomaly caused by defect dipole polarization was observed in temperature-dependent dielectric constant curves, for 6% and 8% Mn-doped samples. This study is helpful to establish the relationship between the structure, morphology, dielectric and ferroelectric properties of Mn substituted Ba0·7Sr0·3TiO3 ceramics.

Promotional effect of Mn doping on Ru/layered MCM-49 catalysts for the conversion of Levulinic acid to γ-Valerolactone

Selective hydrogenation of Levulinic acid (LA) to γ-Valerolactone (GVL) is an important reaction to produce high value-added chemicals and fuels but remains a big challenge. Herein we reported a Ru/zeolite catalyst with Mn promotion, which exhibited excellent catalytic performance (yield: 98%) towards LA to GVL. The intrinsic activity (TOF) also increased obviously with the Mn addition. The particle size of Ru gradually decreased with the increase of Mn loading and a strong interaction between Ru and support was observed for the Ru-Mn/MCM-49 catalyst. The addition of Mn not only offered a good dispersion of Ru species on MCM-49, but also increased the L/B ratio of the catalyst, thereby contributing to the high GVL selectivity. High dispersed Ru sites were the intrinsic active sites of the catalyst verified by the in-situ experimental studies. The dissociation of the reactants was significantly enhanced, resulting in higher catalytic activity.

Bulk superconductivity in one-step grown Fe(Te,Se) crystals free of interstitial iron by minor Mn doping

The iron-based nontoxic chalcogenide superconductor Fe(Te,Se) has great potential for high magnetic field applications while it lacks a reliable method to produce bulk superconductor so far. Here we report a one-step synthesis method to grow high-quality Fe(Te,Se) single crystals free of interstitial iron atoms through minor Mn doping. Bulk superconductivity is revealed in the as-grown centimeter-sized crystals with the optimal doping level of 1% Fe atoms substituted by Mn, which is systematically demonstrated by sharp electrical resistivity and magnetic susceptibility transitions, and large specific heat jumps. Compared with the un-doped sample, the optimally doped one shows a significantly enhanced upper critical field, and a large self-field critical current density Jc of 4.5 × 105 A cm−2 at 2 K (calculated by the Bean model), which maintains large values under high fields. The absence of interstitial iron atoms is testified by the scanning tunneling microscopy, and the effect of Mn doping is discussed. Our results provide a practical method by minor Mn doping to directly synthesize high-performance Fe(Te,Se) bulks that allow for future high-field superconducting applications.

Effect of Mn doping on the structural, optical, magnetic properties, and antibacterial activity of ZnO nanospheres

This work investigates the systematic study of the structural, optical, magnetic, and antibacterial properties of Mn-doped ZnO. Zinc oxide (ZnO) and Mn2+ doped zinc oxide (ZnMnO) nanoparticles (NPs), were prepared through the co-precipitation method. The X-ray diffraction studies confirmed that the synthesized nanoparticles did not modify the crystal structure upon Mn doping. However, the microstructural parameters were changed considerably upon the increase of the concentration of Mn dopant. The HRTEM images showed that the ZnO NPs exhibit nanospheres-like morphology, and a reduction in the average particle size from 41 nm to 33 nm was observed upon Mn2+ doping. The elemental composition of Zn, Mn, and O atoms were identified by EDAX spectra. The Zn–O stretching bands were observed at around 550 cm−1 in the FTIR spectra and the zinc and oxygen vacancies defects were confirmed by PL spectra. The estimated band gap of ZnO was 2.95 eV and increased to 3.14 eV for ZnMnO3. In addition, the Mn-doped ZnO NPs showed a more significant antibacterial effect than the pure ZnO NPs. The ZnO and Mn-doped ZnO NPs showed significant changes in the M-H loop where the diamagnetic behavior of ZnO changes to a weak ferromagnetic nature when doped with Mn ions. Graphical abstract

Boosting the electrochemical performance of LiNiO2 by extra low content of Mn-doping and its mechanism

The urgent demands of developing Co-free materials for lithium ion batteries with high energy density for next generation electric vehicles have driven the attention of researches to LiNiO2 stabilized by doping of common elements. Among those elements, manganese is usually used to stabilize cathode material crystal structures to achieve better electrochemical performances. However, the Li+/Ni2+ cation disorder causing by Mn doping is greatly neglected of the effect on electrochemical behaviors. In order to elucidate the exact effect of Mn-doping, herein, we synthesize Mn-doped LiNiO2 with extra low Mn content by using the solid-state element thermal interdiffusion strategy. Under calcination at high temperature, with the spherical species coated with Mn-containing gel as the precursor, Mn can be evenly doped into the framework of LiNiO2 material. It is demonstrated that the small amount of Mn-doping can greatly stabilize both the crystal structure of LiNiO2 and integrity of the secondary particles during the electrochemical cycling to provide the excellent electrochemical cycling performance and thermal stability of the materials. Nevertheless, the rate capability of the materials is strongly dependent on the amount of the doped Mn, due to the Li+/Ni2+ cation mixing formed in the synthesis process and introduced in the electrochemical cycling. In the presence of a tiny quantity of the doped Mn, the enlarged crystal lattice would be favorable to the diffusion of the Li+ ions in the crystal. However, serious Li+/Ni2+ cation mixing of the materials with high content of the Mn-doping deteriorates the rate performance of the materials. Thus, in this case, the Mn content is optimized to be 4 mol%, endowing the material with an initial capacity of 202 mAh g−1 at 0.1 C, and a capacity retention of 85.41% after 200 cycles at 0.5 C. For the Mn-doped LiNiO2 materials, it is suggested that to control the Li+/Ni2+ cation mixing would be crucial for gaining the materials with superior electrochemical performance.

Effect of Mn doping on the Structural, Dielectric, and Multiferroic Properties of BiFeO₃-BaTiO₃ Ceramics Fabricated by Spark Plasma Sintering

0.67BiFeO₃-0.33BaTiO₃-xwt%Mn ceramics were synthesized using the SPS method. Fine BiFeO₃-BaTiO₃ ceramics with a morphotropic phase boundary were formed, as demonstrated by XRD and SEM. The dielectric constants reached approximately 4000. The ferroelectric properties of Mn-doped BiFeO₃-BaTiO₃ were significantly improved compared with undoped BiFeO₃-BaTiO₃. The highest magnetic properties were obtained when the sintering temperature was 820 ℃ and the doping content was 0.3 wt%, and were superior to those fabricated using other methods. The Mn-doped BiFeO₃-BaTiO₃ multiferroic ceramic synthesized in this work shows promise for application in data storage.

Tribological properties of Mn–TiN films and formation of graphite-like layers in physiological solution

TiN film and Mn–TiN films containing 2.2, 5.6, and 10.6 at% Mn were deposited on appropriate substrates using a four-target unbalanced magnetron sputtering system. The Mn contents of films were adjusted by controlling the number of Ti–Mn alloy rods embedded in the titanium target. The effects of Mn doping on the microstructure, mechanical properties, and wear properties of TiN films were systematically investigated. A relatively loose columnar structure is observed in the TiN film, which is refined and densified by the incorporation of Mn. Mn doping improves the hardness, toughness, and adhesion performance of TiN films. The Mn–TiN films containing 2.2 and 5.6 at% Mn, in particular, exhibit superior mechanical properties. Moreover, the presence of Mn has a promoting effect on the wear of TiN films in both phosphate buffer (PB) and bovine serum albumin (BSA) solutions. The Mn ions released from Mn–TiN films during friction in a BSA solution promote the formation of protein deposits. The structures of protein molecules in these deposits denature under the frictional shear force of SiC balls during sliding tests, forming graphite-like layers on the friction interfaces. These layers act as a solid lubricant and improve the wear resistance of films.