Zr Doping Research Articles

Synergistic Strain Suppressing and Interface Engineering in Na4MnV(PO4)3/C for Wide-Temperature and Long-Calendar-Life Sodium-Ion Storage.

A Na4MnV(PO4)3 (NMVP) cathode is regarded as a promising cathode candidate for sodium-ion batteries (SIBs). However, issues such as low electronic conductivity and partial cation dissolution contribute to high polarization and structure distortion. Herein, we engineered the local electron density and reaction kinetic properties of NMVP cathodes with varying oxygen vacancies by introducing varying amounts of Zr doping and carbon coating. The optimized sample exhibited a high-rate capacity of 71.8 mAh g-1 at 30 C (83.1% capacity retention after 1000 cycles) and excellent performance over a wide temperature range (84.1 mAh g-1 at 60 °C and 61.4 mAh g-1 at -30 °C). In situ X-ray diffraction technology confirmed a redox solid solution and a two-phase reaction mechanism, revealing minor changes in cell volume and slight strain variations after Zr doping, effectively suppressing the structural distortion. Theoretical calculations illustrated that Zr doping largely shrinks the band gap of NMVP, enriches local electron density, and slightly alters the local element distribution and bond lengths. Moreover, full-cells have shown high energy density (259.9 Wh kg-1) and outstanding cycling stability (200 cycles). The work provides fresh insights into the synergistic effect of strain suppressing and interface engineering in promoting the development of wide temperature range and long-calendar-life SIBs.

Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

Magnesium (Mg) alloys are widely used for temporary bone implants due to their favorable biodegradability, cytocompatibility, hemocompatibility, and close mechanical properties to bone. However, rapid degradation and inadequate strength limit their applicability. To overcome this, the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium (Zr) content. This approach presents a promising strategy for simultaneously improving corrosion resistance, maintaining biocompatibility, and enhancing strength without compromising osseointegration. By leveraging Mg's inherent biodegradability, it has the potential to minimize the need for secondary surgeries, thereby reducing costs and resources.This paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings, denoted Mg-xZr (x = 0–5 at.%). Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr content. XRD analysis confirmed the presence of the Mg (00.2) basal plane, shifting towards higher angles (1.15°) with 5 at.% Zr doping due to lattice parameter changes (i.e., decrease and increase of “c” and “a” lattice parameters, respectively). Mg–Zr coatings exhibited “liquidphilic” behavior, while Young's modulus retained a steady value around 80 GPa across all samples. However, the hardness has significantly improved across all samples’ coating, reaching the highest value of (2.2 ± 0.3) GPa for 5 at.% Zr. Electrochemical testing in simulated body fluid (SBF) at 37 °C revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.% Zr. Compared with the 5 at.% Zr coating which exhibited a corrosion rate of 32 mm/year, these coatings displayed lower corrosion rates, ranging from 1 to 12 mm/year. This synergistic enhancement in mechanical properties and corrosion resistance, achieved with 2.0–3.4 at.% Zr, suggests potential ability for reducing stress shielding and controlled degradation performance, and consequently, promising functional biodegradable materials for temporary bone implants.

Enhanced stability and catalytic activity of subnanometric platinum cluster by surface doping of zirconium in CeO2

There has been a continuous effort to improve the thermal stability of subnanometric platinum (Pt) cluster (<2 nm) catalyst because Pt cluster on CeO2 support can be mobile and aggregated into nanoparticle on heating at elevated temperatures, yet this great challenge remains. In this study, a strategy is reported to improve the thermal stability of subnanometric Pt cluster by hydrothermal deposition method. Based on this method, zirconium (Zr) was precisely doped on surface of Ce0.95Zr0.05O2 by accurate control of Pt subnanometric cluster size. The surface doping of Zr is favorable for forming the Zr–O–Ce site and activating surface lattice oxygen atoms, which results in strong electronic interactions to stabilize the Pt subnanometric cluster. After high-temperature aging treatment at 1000 °C/4 h, the single atom Pt supported on CeO2 is aggregated into larger sized (>3 nm) nanoparticle. In contrast, the single atom Pt supported on Ce0.95Zr0.05O2 displays less agglomeration into subnanometric cluster with size of (1.4 ± 0.3) nm. Moreover, the CO oxide catalytic performance of Ce0.95Zr0.05O2–Pt is 26 % and 31 % higher than that of CeO2–Pt and commercial Al2O3–Pt catalysts, respectively. The experimental and density functional theory (DFT) calculations indicate that the Zr–O–Ce site and Pt subnanometric cluster interface have more defect sites and active oxygen species than CeO2–Pt interface, which activate the Mars van Krevelen (MvK) mechanism, facilitating the catalytic performance.

Grain-boundary-dependent segregation and phase separation in ceria–zirconia from atomistic simulation

Doping is the most common strategy employed in the development of new and improved materials. However, predicting the effects of doping on the atomic-scale structure of a material is often difficult or limited to high-end experimental techniques. Doping can induce phase separation in a material, undermining the material’s stability. A further complication is that dopant atoms can segregate to interfaces in a material such as grain boundaries (GBs), with consequences for key macroscopic properties of the material such as its conductivity. Here, we demonstrate a computational methodology based on semi-grand canonical Monte Carlo which can be used to probe these phenomena at the atomic scale for metal oxide solid solutions. The methodology can provide precise predictions of the thermodynamic conditions at which phase separation occurs. It can also provide the segregation patterns exhibited by GBs at given conditions. We apply the methodology to one of the most important catalytic materials, ceria–zirconia. Our calculations reveal an interesting richness in the GB segregation in this system. Most GBs we examined exhibited continuous increases in Zr segregation upon Zr doping, with a concomitant reduction in the formation enthalpies of the GBs. However, a few GBs exhibited no segregation at low temperatures. We also observed evidence of first-order complexion transitions in some GBs.

Effects of Zr dopants on properties of PtNi nanoparticles for ORR catalysis: A DFT modeling.

Pt-based alloys, such as Pt3Ni, are among the best electrocatalysts for oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells. Doping of PtNi alloys with Zr was shown to enhance the durability of the operating ORR catalysts. Rationalizing these observations is hindered by the absence of atomic-level data for these tri-metallic materials, even when not exposed to the fuel cell operation conditions. This study aims at understanding structure-property relations in Zr-doped PtNi nanoparticles as a key to their ORR function. In particular, we calculated, using a method based on density functional theory, the most stable chemical orderings of pristine and Zr-doped Pt3Ni particles containing over 400 atoms. We thus clarify (i) preferential location and charge states of Zr atoms in the Pt3Ni NPs; (ii) effect of doping Zr atoms on the stability of the Pt skin of the Pt3Ni NPs; (iii) charge redistribution induced by Zr dopants; (iv) layer-by-layer atomic ordering in the Pt3Ni/Zr NPs with the increasing Zr content; and (v) effect of Zr atoms on the adsorption energies of O and OH species as indicators of the ORR activity.

Fabrication of TiO2 photoelectrodes doped with copper and zirconium to improve electron generation and flow in dye-sensitized solar cell

Dye-sensitized solar cell (DSSC) are devices that convert solar light into electricity using a semiconductor substance, e.g. TiO2. Although DSSC are environmentally friendly and economical, they exhibit a low energy conversion efficiency. In this study, to improve its energy conversion efficiency, a DSSC in which TiO2 was doped with transition metals (TMs) such as Cu and Zr was fabricated by a sol–gel method. Doping with TMs extended the light-absorption range of TiO2 to the visible-light region, generating more electrons and improving electrical conductivity. The successful doping of Cu, Zr in the fabricated photoelectrode was confirmed by X-ray diffraction (XRD) and FESEM–energy dispersive X-ray spectroscopy (EDS) analyses, and doping with Cu, Zr increased the dye adsorption amount and current density of DSSC. In addition, the electron-transfer resistance was confirmed to be reduced by electrochemical impedance spectroscopy (EIS) analysis, and the electron movement, speed, and lifetime were improved by Intensity-modulated photocurrent spectroscopy (IMPS) and intensity-modulated photovoltage spectroscopy (IMVS) analyses. The electrical properties of the Cu, Zr-doped TiO2 photoelectrodes were determined from the chemical capacitance and recombination resistance calculations, and the results revealed that the efficiency was improved by Cu, Zr doping. In conclusion, the Cu, Zr doping of the photoelectrode improved the electron generation and flow of TiO2, thereby increasing the energy conversion efficiency of the DSSC by up to 3.28%

Enhanced Ru-O-Ce interaction by solid solution structure of Ru-CexZr1-xO2 catalysts for efficient catalytic combustion of vinyl chloride

Ru-CexZr1-xO2 catalysts, prepared by stepwise precipitation method, were investigated for the catalytic combustion of vinyl chloride (VC). Ru-O-Ce is a highly reactive structure in the redox ability. The Ce-O-Zr solid solution structure enhances the strong metal-support-interaction (SMSI) between Ru and Ce, thereby increasing the content of Ru-O-Ce structure, which can be modulated by the molar ratio of Ce/(Ce + Zr) in the catalyst. Zr doping also enhances the surface acid sites. In situ DRIFTS reveals that Ru-CexZr1-xO2 catalyst avoids chlorine poisoning, and Ru-O-Ce provides sufficient chemically adsorbed oxygen species (CAOS) to promote formation of formate intermediate species. Ru-Ce0.5Zr0.5O2 catalyst exhibited the best catalytic performance with T90 of 227 °C under the reaction conditions of 1000 ppm VC and WHSV of 30,000 mL·g−1·h−1. Moreover, Ru-Ce0.5Zr0.5O2 catalyst exhibited the superior resistance to high temperature, chlorine poisoning and water, and excellent catalytic activity for the catalytic combustion of various VOCs.

Theoretical Maximum Thermoelectric Performance of p‐Type Hf‐ and Zr‐Doped NbFeSb Half‐Heusler Compounds

AbstractHalf‐Heusler compounds are promising materials for thermoelectric applications due to their high zT at elevated temperatures. However, their intrinsic high thermal conductivity limits their efficiency. Doping with Hf or Zr can improve the zT of these materials. Recently, a high zT of 1.5 at 1200 K achieved in p‐type Nb1‐xHfxFeSb has attracted much attention. While the effect of doping Hf in thermal conductivity is studied thoroughly, the effect of Hf doping on band parameters is not fully evaluated. This study investigates the effect of Hf and Zr doping on the electronic band parameters and thermoelectric properties of NbFeSb using the Single Parabolic Band model. The results show that Hf doping increases the weighted mobility of the samples, while Zr doping has no significant effect. Hf doping with x = 0.14 is predicted to improve the zT of NbFeSb by 35% at 300 K (0.19 → 0.26). These results show the intricate effects of Hf and Zr doping on the electronic and thermal properties of NbFeSb.

Polarization switching pathways of ferroelectric Zr-doped HfO2 based on the first-principles calculation

Based on the first principles calculation, the mechanisms of polarization switching behavior in ferroelectric Zr-doped HfO2 are investigated. Seven switching pathways, divided into two categories by the identified orientation of polarization switching and value, are analyzed based on atomic migration and energy barrier. The effects of Zr dopant on switching energy barrier (Eb) and spontaneous polarization (Ps) are analyzed as well. In one of the categories, two pathways with tetragonal-like transition states show low energy barriers and can be further minimized with higher Zr dopant proportion, which originates from the stabilizing effect of Zr dopant on the tetragonal phase (T, P42/nmc). Especially, in the two tetragonal-like pathways, a distorted tetragonal-like transient state (T′, Pbcn) resulting from distinct atomic displacement is transformed to a highly symmetric T-phase along with the incorporation of Zr, elucidating this pathway as energy favorable as the regular T-pathway. This work provides an atomic insight for ferroelectric switching behavior and predicts the probable ferroelectric switching pathway in Zr-doped HfO2 films.

Improving Photocatalytic activity of (100) and (111) TiO2 nanosheets by coupling with ZrO2 and HfO2 nanosheets; A DFT-U study

In this work, density functional theory was employed to study the enhancement of the photocatalytic efficiency of TiO2 nanosheets by doping it with Zr and Hf atoms and coupling it with ZrO2 and HfO2 nanosheets. The (111) TiO2 was found to be more efficient than the (100) TiO2 nanosheet due to its narrower bandgap and larger specific surface area. Hf doping was found to improve the photocatalytic efficiency of (111) TiO2 nanosheet, whereas Zr doping may lead to limitations. The study also demonstrated that the most effective type II heterojunctions were formed by combining pristine and Zr-doped (101) HfO2 nanosheets with pristine, Zr-, and Hf-doped (111) TiO2 nanosheets.

Enhanced Electrocatalytic Oxygen Reduction Reaction of TiO2 Nanotubes by Combining Surface Oxygen Vacancy Engineering and Zr Doping.

This work examines the cooperative effect between Zr doping and oxygen vacancy engineering in anodized TiO2 nanotubes (TNTs) for enhanced oxygen reduction reactions (ORRs). Zr dopant and annealing conditions significantly affected the electrocatalytic characteristics of grown TNTs. Zr doping results in Zr4+ substituted for Ti4+ species, which indirectly creates oxygen vacancy donors that enhance charge transfer kinetics and reduce carrier recombination in TNT bulk. Moreover, oxygen vacancies promote the creation of unsaturated Ti3+(Zr3+) sites at the surface, which also boosts the ORR interfacial process. Annealing at reductive atmospheres (e.g., H2, vacuum) resulted in a larger increase in oxygen vacancies, which greatly enhanced the ORR activity. In comparison to bare TNTs, Zr doping and vacuum treatment (Zr:TNT-Vac) significantly improved the conductivity and activity of ORRs in alkaline media. The finding also provides selective hydrogen peroxide production by the electrochemical reduction of oxygen.

Mitigated Oxygen Loss in Lithium‐Rich Manganese‐Based Cathode Enabled by Strong Zr–O Affinity

AbstractOxygen loss is a serious problem of lithium‐rich layered oxide (LLO) cathodes, as the high capacity of LLO relies on reversible oxygen redox. Oxygen release can occur at the surface leading to the formation of spinel or rock salt structures. Also, the lattice oxygen will usually become unstable after long cycling, which remains a major roadblock in the application of LLO. Here, it is shown that Zr doping is an effective strategy to retain lattice oxygen in LLO due to the high affinity between Zr and O. A simple sol‐gel method is used to dope Zr4+ into the LLOs to adjust the local electronic structure and inhibit the diffusion of oxygen anions to the surface during cycling. Compared with untreated LLOs, LLO–Zr cathodes exhibit a higher cycling stability, with 94% capacity retention after 100 cycles at 0.4 C, up to 223 mAh g−1 at 1 C, and 88% capacity retention after 300 cycles. Theoretical calculations show that due to the strong Zr–O covalent bonding, the formation energy of oxygen vacancies has effectively increased and the loss of lattice oxygen under high voltage can be suppressed. This study provides a simple method for developing high‐capacity and cyclability Li‐rich cathode materials for lithium‐ion batteries.

First-principles study on the effects of Zr doping and interstitial H and O vacancy on the optoelectronic properties of β-Ga2O3

In this work, the electronic structure and optical properties of Zr-doped [Formula: see text]-Ga2O3 with interstitial H and O vacancies were studied by using first-principles generalized gradient approximation combined with the Hubbard U method based on density functional theory. The energy band structure, density of states, absorption spectrum, effective mass, mobility and conductivity of the doped system were calculated and analyzed. Results showed that the doped system was more stable under the Ga-rich condition than under the O-rich condition. With the increase in Zr doping concentration, the bandgap of the [Formula: see text]-Ga2O3 system gradually narrowed and the absorption spectrum of the system blue-shifted in the wavelength range of 162–275[Formula: see text]nm. System conductivity was enhanced by Zr doping, decreased by O vacancies and greatly improved by interstitial H. Therefore, doping Zr into the [Formula: see text]-Ga2O3 system is important for improving material properties and preparing electronic and optical devices.

Strengthening by Ti, Nb, and Zr doping on microstructure, mechanical, tribological, and corrosion properties of CoCrFeNi high-entropy alloys

CoCrFeNi high entropy alloys (HEAs) are renowned for their exceptional ductility and corrosion resistance, positioning them as promising contenders in corrosion-resistant wear applications. Nonetheless, their intrinsic drawback lies in relatively diminished strength and hardness. This study delves deep into elucidating the mechanisms through which the incorporation of dopant elements augments the strength and toughness of CoCrFeNi HEAs. High-speed laser cladding (HLC) was employed to fabricate CoCrFeNi HEAs coatings, and the influence mechanisms of Ti, Nb, and Zr dopants on coating phase structure, microstructure, elemental distribution, microhardness, tensile properties, tribological performance, and electrochemical corrosion resistance were investigated. The results show that Ti boasts the highest affinity for solubility within the CoCrFeNi matrix, preserving its inherent FCC simple solid solution configuration. In contrast, Nb and Zr exhibit diminished solubility, culminating in the emergence of BCC phases and intermetallic compounds. In terms of strengthening mechanisms, the addition of Ti primarily contributes to solid solution strengthening, enhancing the strength, hardness, and wear resistance of CoCrFeNi HEAs coatings, with minimal impact on their ductility, resulting in coatings with optimal corrosion resistance. The introduction of Nb generates an interdendritic eutectic microstructure and shifts the dominant crystallographic plane from (200) to (111) in the FCC phase, leading to superior strength and wear resistance. The incorporation of Zr results in the formation of numerous Ni11Zr9 intermetallic compounds in the interdendritic regions, significantly deteriorating both ductility and corrosion resistance. This comprehensive investigation furnishes pivotal empirical insights and theoretical frameworks, setting the stage for the judicious optimization of HEAs in advanced material applications.

Enhancing DMC Production from CO2: Tuning Oxygen Vacancies and In Situ Water Removal

The direct synthesis of dimethyl carbonate (DMC) from methanol and CO2 presents an attractive route to turn abundant CO2 into value-added chemicals. However, insufficient DMC yields arise due to the inert nature of CO2 and the limitations of reaction equilibrium. Oxygen vacancies are known to facilitate CO2 activation and improve catalytic performance. In this work, we have demonstrated that tuning oxygen vacancies in catalysts and implementing in situ water removal can enable highly efficient DMC production from CO2. CexZryO2 nanorods with abundant oxygen vacancies were synthesized via a hydrothermal method. In liquid-phase DMC synthesis, the Ce10Zr1O2 nanorods exhibited a 1.7- and 1.4-times higher DMC yield compared to CeO2 nanoparticles and undoped CeO2 nanorods, respectively. Zr doping yielded a CeZr solid solution with increased oxygen vacancies, promoting CO2 adsorption and activation. In addition, adding 2-cyanopyridine as an organic dehydrating agent achieved an outstanding 87% methanol conversion and &gt;99% DMC selectivity by shifting the reaction equilibrium to the desired product. Moreover, mixing CeO2 nanoparticles with hydrophobic fumed SiO2 in gas-phase DMC synthesis led to a doubling of DMC yield. This significant increase was attributed to the faster diffusion of water molecules away from the catalyst surface, facilitated by the hydrophobic SiO2. This study illustrates an effective dual strategy of enhancing oxygen vacancies and implementing in situ water removal to boost DMC production from CO2. The strategy can also be applied to other reactions impacted by water accumulation.

Surficial engineering of active hydroxyls for ambient formaldehyde oxidation via enhanced Lewis acidity over Zr-doped cryptomelane materials

Lewis acids of solid catalysts have been featured for a pivotal role in promoting various reactions. Regarding the oxidation protocol to remove formaldehyde, the inherent drawback of the best-studied MnO2 materials in acidic sites has eventually caused deficiency of active hydroxyls to sustain low-temperature activity. Herein, the cryptomelane-type MnO2 was targeted and it was tuned via incorporation of Zr metal, exhibiting great advances in not only the complete HCHO-to-CO2 degradation but also cycling performance. Zr species were existent in doping state in the MnO2 lattice, rendering lower crystallinity and breaking the regular growth of MnO2 crystallites, which thereby tripled surface area and created larger volume of smaller mesopores. Meantime, the local electronic properties of Mn atoms were also changed by Zr doping, i.e., more low-valence Mn species were formed due to the electron transfer from Zr to Mn. The results of infrared studies demonstrate the higher possession of Lewis acid sites on ZrMn, and this high degree of electrophilic agents favored the production of hydroxyl species. Furthermore, the reactivity of surface hydroxyls, as investigated by CO temperature programmed reduction and temperature programmed desorption of adsorbed O2, was obviously improved as well after Zr modification. It is speculated jointly with the characterizations of the post-reaction catalysts that the accelerated production of active hydroxyls helped rapidly convert formaldehyde into key intermediate—formate, which was then degraded into CO2, avoiding the side reaction path with undesired intermediate—hydrocarbonate—over the pristine MnO2, where active sites were blocked and formaldehyde oxidation was inhibited. Additionally, Zr decoration could stabilize Lewis acidity to be more resistant to heat degeneration, and this merit brought about advantageous thermal recyclability for cycled application.

Adhesion, bonding and electronic properties of Ti/Zr doped c-BN(100)/Cu(100) interfaces: A first-principles study

Brazed monolayer cubic boron nitride (c-BN) tools are considered as promising tools for machining ductile metal materials. The interface between c-BN and filler alloys determines the properties of the tools to some extent. This paper uses first-principles calculations to study the atomic structures, work of adhesion, electronic properties, and density of states of c-BN(100)/Cu(100) clean and doped interfaces where the doping atoms are Ti/Zr. In this paper, four types of models are considered and calculated. The calculations reveal that Ti doping and Zr doping both increase the work of adhesion of the c-BN(100)/Cu(100) interface and the highest increase rate is 109 % and 83.4 %, respectively. The work of adhesion of c-BN(100)/Cu(100) interface doped with Ti is much higher than that doped with Zr and the electronic properties and density of states also prove this point of view. To sum up, Ti and Zr are both effective active elements to improve the performance of the c-BN/Cu interface, but, by comparison, Ti has better wettability to c-BN than Zr which provides an interpretation of the reported experimental results through the view of the atomic structures, work of adhesion, electronic properties and density of states.

Role of Zr in promoted activity of urea oxidation reaction and oxygen evolution reaction for NiFe layered double hydroxide

Electrolysis of water and splitting of urea to produce hydrogen are identified as one of the most attractive approach to reduce environmental pollution. However, this approach is both promising and challenging. In the paper, the NiFeZr LDH material was in situ grown on Ni foam through a one-step hydrothermal process. The electrochemistry activity of the NiFeZr LDH electrode was investigated by two probe reactions, one for the oxidation of urea and the other for the oxidation of water. It is worth mentioning that whether it is the oxidation reaction of urea (potential of 1.42 V @ 10 mA cm−2) or water (overpotential of 350 mV @ 10 mA cm−2), the doping of Zr improves the catalytic activity of the material. What is worth mentioning that the oxidation of urea does significantly decrease energy consumption compared to the oxidation of water. However, experiments show that the catalytic active sites are different in the two reactions. We speculate that iron is the active site for the oxidation of water, while zirconium is the active site for the oxidation of urea. Experiments demonstrate that the promoted performance is assigned to the exposure of the centre site, the rapid charge transfer rate and the improved electron configuration. Density functional theory analysis indicates that this NiFeZr LDH electrode presents optimal adsorption energy for urea, which improves the catalytic activity of the material.

Realizing ferromagnetic semiconductors in SrRu1−xZrxO3 alloys

Using first principle calculations, we study the structural, electric and magnetic properties of SrRu1−xZrxO3 (0 ≤ x ≤ 1). The spin-polarization calculations present that SrRu1−xZrxO3 is a ferromagnetic metal at x = 0, a ferromagnetic semiconductor at x = 0.125, 0.25, an antiferromagnetic semiconductor at x = 0.5 and a nonmagnetic insulator at x = 1, which is in agreement with available experiments. As increasing Zr contents, the lattice parameters and band gaps of SrRu1−xZrxO3 increase while the energy difference between antiferromagnetic and ferromagnetic states decreases. Through Ru-O and Zr-O bonds, hybridization between Ru 4d and Zr 4d states near the Fermi level becomes strong. As a result, Ru 4d states split and then metal-insulator transition occurs at x = 0.125 due to Zr. Ferromagnetic semiconductors are first predicted in SrRu1−xZrxO3 alloys, which may have potential applications in spintronic devices.

Different metal (Mn, Fe, Co, Ni, and Zr) decorated Cu/CeO2 catalysts for efficient CO oxidation in a rich CO2/H2 atmosphere.

In this work, CuM/CeO2 (M = Mn, Fe, Co, Ni, and Zr) catalysts with a low Cu content of 1 wt% were purposely designed and prepared using the co-impregnation method. The samples were characterized using various techniques (TG-DTA, XRD, N2-adsorption/desorption measurements, H2-TPR, XPS and Raman spectroscopy) and CO preferential oxidation (CO-Prox) under H2/CO2-rich conditions was performed. The results have shown that enhanced catalytic performance was achieved upon the introduction of Mn, Co and Ni, and little impact was observed with Zr doping, but Fe showed a negative effect, as compared with the Cu/CeO2 catalyst. Characterization data revealed that the M doping strongly changed the surface composition, revealing the decreased Cu/Ce ratios on the surface, which could be accounted for by the formation of more M/Cu-O-Ce solid solution, or strong Cu-M interactions. When Mn was used, the obtained CuMn/CeO2 catalyst revealed the highest concentration of the oxygen vacancies and Ce3+ ions, which could be correlated well with its superior catalytic performance. Compared with the Cu/CeO2 catalyst, the CO conversion rate increased by 24.7% at a low temperature of 90 °C over the CuMn/CeO2 catalyst. At 130 °C, the maximum CO conversion was 94.7% and the CO2 selectivity was 78.9%. Conversely, the Fe doped Cu/CeO2 catalyst demonstrated the poorest catalytic activity, which was due to the blockage effect of Fe species on Cu showing a high Fe/Cu ratio of 1.9 on the surface.