CeO2 Support Research Articles

Polyoxometalates‐Mediated Selectivity in Pt Single‐Atoms on Ceria for Environmental Catalysis

AbstractOptimizing the reactivity and selectivity of single‐atom catalysts (SACs) remains a crucial yet challenging issue in heterogeneous catalysis. This study demonstrates selective catalysis facilitated by a polyoxometalates‐mediated electronic interaction (PMEI) in a Pt single‐atom catalyst supported on CeO2 modified with Keggin‐type phosphotungstate acid (HPW), labeled as Pt1/CeO2‐HPW. The PMEI effect originates from the unique arrangement of isolated Pt atoms and HPW clusters on the CeO2 support. Electrons are transferred from the ceria support to the electrophilic tungsten in HPW clusters, and subsequently, Pt atoms donate electrons to the now electron‐deficient ceria. This phenomenon enhances the positive charge of Pt atoms, moderating O2 activation and limiting lattice oxygen mobility compared to the conventional Pt1/CeO2 catalyst. The resulting electronic structure of Pt combined with the strong and local acidic environment of HPW on Pt1/CeO2‐HPW leads to improved efficiency and N2 selectivity in the degradation of NH3 and NO, as well as increased CO2 yield when inputting volatile organic compounds. This study sheds the light on the design of SACs with balanced reactivity and selectivity for environmental catalysis.

Boosting Dry Reforming of Methane Over NiCo/CeO2 Catalysts Treated by Hydrogen Plasma

ABSTRACTNickel (Ni)‐based catalysts are prospective materials for dry reforming of methane (DRM) reaction, but suffer from coke formation and limited activity for CO2 conversion. To improve the reactivity of Ni‐based catalysts, a promising strategy is introducing cobalt (Co) metal. Here, we construct highly efficient NiCo sites on CeO2 support by H2 plasma, which enables the catalyst to obtain a remarkable increase in DRM reaction than the samples treated by conventional H2 reduction. H2 plasma treatment results in the formation of highly dispersed NiCo alloy nanoparticles and high‐concentration oxygen vacancy. These features create large numbers of highly active sites to boost the activation of CH4 and especially CO2 and their catalytic reactions, resulting in strong coke resistance in the DRM reaction.

Impact of Flame Conditions on the Pd‐O Structure and Methane Oxidation Activity over Ceria Support

AbstractIn this work, we employed flame spray pyrolysis (FSP), a high‐temperature synthesis method, to control the formation of Pd structures on the CeO2 support. Multiple types of Pd structures deposited on CeO2 are observed on FSP‐made samples. Our results show that the oxidizing environment during FSP synthesis facilitates the formation of incorporated Pd2+ structures, along with highly dispersed Pd2+, Pd0 nanoparticles, and Pd° clusters formed under the reducing synthesis condition. Notably, these Pd2+ species remained stable at temperatures up to 400 °C. The catalysts containing both highly dispersed Pd2+ nanoparticles and incorporated Pd2+ species demonstrated superior methane oxidation activity, with higher turnover frequencies than those containing only one type of Pd2+ structure. However, hydrothermal pretreatment in the presence of water vapor led to partial deactivation, likely due to structural alterations in the Pd species or the interaction with the CeO2 support, which reduced the stability and effectiveness of the active sites. This study underscores the importance of both highly dispersed and incorporated Pd2+ species in enhancing catalytic performance and highlights the challenges posed by water‐induced deactivation in practical applications.

Atomically dispersed Ir Lewis acid sites on (111)-oriented CeO2 enable enhanced reaction kinetics for Li-O2 batteries

Non-aqueous lithium-oxygen batteries are widely regarded as one of the most promising electrochemical energy storage systems, with their ultra-high theoretical energy density and environmental friendliness. However, the sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) kinetics hinder their practical application. In this study, we tailored an atomically dispersed Ir site on a CeO2 support (Ir@CeO2) with {111} facet-dependent activity to enhance cathode reaction kinetics. The charge interaction between Ir and Ce atoms results in the appropriate regulation of the d-band center of Ir sites leaping into the Fermi energy level, demonstrating a stronger Lewis acidity, which enables easier electron injection from the Ir d-orbitals into O 2p-orbitals of LiO2. This facilitates the conversion kinetics, and as a result, the lithium-oxygen battery with Ir@CeO2 catalyst delivers a minimal discharge/charge polarization and long-term cycle stability, outperforming most traditional catalysts reported. Our promising findings offer compelling insights into the precise manipulation of d orbital structures and the optimization of Lewis acidity, paving the way for advanced electrocatalyst design.

Oxygen and Electron Storage Effects in W-Modified Ceria Catalysts for Ammonia Conversion.

Tungsten-modified CeO2 is an excellent catalyst for the catalytic conversion of ammonia. However, the geometric and electronic properties of this catalyst and the detailed reaction mechanisms are not well understood. In this work, the potential configurations of various monomer tungsten oxides supported on the CeO2(111) surface (WOX(x=0-4)/CeO2(111)) are systematically studied and their relative stabilities are evaluated by using on-site Coulomb interaction corrected density functional theory calculations. Their performances are also investigated in enhancing the catalytic efficiency of NH3 adsorption and activation. It is found that the WOx clusters can always form tetrahedron-like structures on the CeO2(111) surface, and the CeO2(111) can exhibit both oxygen- and electron-storage roles to help the WOX maintain such tetrahedron-like WO4 structures and keep the W species at the highest 6+ state. Moreover, the flexibility of the tetrahedral WO4 structure leads to the preferential heterolytic NH3 dissociation at the WO sites, forming stable WNH2 and OH species. This study deepens the understanding of the unique oxygen- and electron-storage effects of the CeO2 support, it also provides valuable insights into the extraordinary catalytic properties of the W-modified CeO2 in NH3 conversion, paving the way for the rational design of more efficient CeO2-based NH3 treatment catalysts.

Deciphering the structural origin for the remarkable CO oxidation activities of the CuO-based catalysts with diverse morphological CeO2 supports

In this work, octahedral, cubic, particle-like, spherical and rod-shaped nano-CeO2 supports were synthesized by hydrothermal method. CuO/CeO2 catalysts were then prepared via an ultrasonic-assisted impregnation method, employing these differently shaped CeO2 supports. The resulting catalysts were tested for their performance in CO oxidation. The findings revealed that the CuO active sites significantly influenced the oxygen storage and release capacity of CeO2, thereby improving its catalytic activity for low-temperature CO oxidation. The key factors affecting the CO oxidation performance of CuO/CeO2 catalysts with different CeO2 morphologies were investigated through various characterizations. It was found that the specific surface area was not the primary factor in determining catalytic activity. Instead, the exposed crystal planes played a crucial role. By adjusting the crystal plane exposure of CeO2, the supported 1CuO/CeO2 catalysts exhibited different crystal surface configurations. Notably, the 1CuO/CeO2-S catalyst, with exposed (100) and (110) crystal planes, and the 1CuO/CeO2-P catalyst, with exposed (111), (100), and (110) planes, exhibited higher surface defect concentrations. This increased defect concentration facilitated the formation of Cu+ species, enhancing the redox properties and further improving the overall catalytic performance of CO oxidation.

Facilitating CO2 methanation over oxygen vacancy-rich Ni/CeO2: Insights into the synergistic effect between oxygen vacancy and metal-support interaction

The catalytic hydrogenation of CO2 into CH4 is a versatile strategy to realize green development goals, whereas developing low-cost and high-performance catalysts remains a significant challenge. Herein, highly active Ni0/NiO supported on oxygen vacancy-rich CeO2 (Ni/CeO2-Ov-R) was designed, which exhibited ∼76 % CO2 conversion coupled with 100 % CH4 selectivity at a low temperature of 250 °C. In addition, such satisfactory reaction performance could be maintained over 80 h at 300 °C. The density functional theory (DFT) calculations elaborated that oxygen vacancies were more easily formed on the CeO2 (1 1 0) plane of Ni/CeO2-Ov-R. Compared with Ni/CeO2-Ov-medium (Ni/CeO2-Ov-M) and Ni/CeO2-Ov-poor (Ni/CeO2-Ov-P) with relatively insufficient oxygen vacancy, the copious oxygen vacancies of Ni/CeO2-Ov-rich was apt to enhance the interaction between the CeO2 support and Ni species as confirmed through H2-TPR and XPS. Noteworthily, the abundant medium-strength basic sites and surface oxygen vacancy of Ni/CeO2-Ov-rich were more conducive to upshifting the activation adsorption of CO2 and accelerate the conversion of intermediates. Besides, the oxygen vacancies also make a great contribution to the enhancement of the potential for hydrogen dissociation because of the enhanced number of exposed Ni0. In situ DRIFTS displayed that the CO and formate (HCOO–) routes co-existed on Ni/CeO2 catalysts, revealing that oxygen vacancy and exposed Ni0 boosted the CO2 and H2 activation. This work proposes a deeper insight into the precise regulation of the oxygen vacancy of Ni/CeO2 catalyst and opens a path for exploiting CO2 methanation catalysts with a potential application.

The influence of CeO2 different morphologies effects on hydrodeoxygenation for guaiacol on Ni/CeO2 catalysts

Catalytic hydrodeoxygenation (HDO) is an effective way to produce high–value products from lignin-derived phenolic compounds. In this work, three different morphologies of Ni/CeO2 catalysts (amorphous, cubic, and rod-shaped) have been prepared through the conventional wet impregnation method. They can be used for the HDO of guaiacol to prepare cyclohexanol, an important chemical raw material. The influence of different morphologies of CeO2 on catalytic activity was explored. The research results indicate that Ni/CeO2–r catalysts with rod-shaped structures exhibit excellent catalytic properties. As a result, a 100 % conversion rate and 96.9 % cyclohexanol yield were achieved on the Ni/CeO2–r catalyst at 240 °C. The catalytic performance of the three catalysts follows this order: Ni/CeO2–r (rod-shaped) > Ni/CeO2–c (cubic) > Ni/CeO2–p (amorphous). The results of Raman and XPS indicate significant differences in the surface oxygen vacancy in catalysts with different morphologies. The Ni/CeO2–r catalyst has the highest oxygen vacancy concentration and defect. In addition, Ni/CeO2–r also has the largest specific surface area (SBET) and the highest nickel dispersion, and forms more Ni0 because of the strong interaction of Ni species and CeO2 support. Therefore, Ni/CeO2–r exhibits the most excellent catalytic performance for the hydrogenation of guaiacol than the other two catalysts. Moreover, the cycling activity test was also investigated over the Ni/CeO2–r catalyst. After five cycles, the conversion rate of guaiacol and the yield of cyclohexanol hardly decrease. This work provides vital ideas for the development of higher-activity, higher-stability, and low-cost catalysts for the conversion of lignin-derived phenolic compounds in the future.

Exploring the nature of copper species: CeO2 support shape effect and its influence on CO2 hydrogenation to methanol

A series of CuO catalysts supported on CeO2 with different morphologies (nanorod, nanocube and hydrangea-like) were tested for the CO2 hydrogenation into methanol. Remarkable morphology-dependent CuO-CeO2 interaction was observed, which was associated with the types and concentrations of copper species. The best performance was obtained over the CuO/hydrangea-like-CeO2 catalyst, giving CO2 conversion of 15.6 % and methanol selectivity of 92.4 % at 260 °C and 3 MPa. The enhanced activity was due to the largest amount of small particle size of copper species, which was responsible for the facile activation of H2. Additionally, the Cu2+-Ov-Cex species facilitated the generation of oxygen vacancies and hydroxyl groups, these two species favored formate production and further hydrogenation to methanol. Moreover, in situ diffuse reflectance infrared fourier transform spectroscopy (in situ DRIFTS) results revealed that the both monodentate formate (m-HCOO*) and bidentate formate (bi-HCOO*) were key and necessary intermediate of CO2 hydrogenation to methanol. The proposed predominate reaction pathway was m-HCOO*→ b-*OCH3 → CH3OH and the minor one was bi-HCOO* → t-*OCH3 → CH3OH.

Hydrogen Production from Methanol Steam Reforming over Fe-Modified Cu/CeO2 Catalysts.

Fe-modified Cu catalysts with CeO2 support, prepared by the impregnation method, were subjected to physicochemical analysis and catalytic tests in the steam reforming of methanol (SRM). Physicochemical studies of the catalysts were carried out using the XRF, TEM, STEM-EDS, XRD, TPR and nitrogen adsorption/desorption methods. XRD, TEM studies and catalytic tests of the catalysts were carried out at two reduction temperatures, 260 °C and 400 °C, to determine the relationship between the form and oxidation state of the active phase of the catalysts and the catalytic properties of these systems in the SRM. Additionally, the catalysts after the reaction were analysed for the changes in the structure and morphology using TEM methods. The presented results show that the composition of the catalysts, morphology, structure, form and oxidation state of the Cu and Fe active metals in the catalysts and the reaction temperature significantly impact their activity, selectivity and stability in the SRM process. The gradual deactivation of the studied catalysts under SRM conditions could result from the forming of carbon deposits and/or the gradual oxidation of the copper and iron phases under the reaction conditions.

Morphology effects of CeO2 on the performance of CaO-Cu/ CeO2 for integrated CO2 capture and conversion to CO

CeO2 support inhibits CaO sintering, and oxygen vacancy influences CO2 hydrogenation performance, making CeO2 widely applied in Integrated CO2 capture and in-situ conversion technology for reverse water–gas shift (ICCC-RWGS). Oxygen vacancy concentration was dependent on the morphology of CeO2, which would affect metal dispersion and CO2 hydrogenation conversion. However, Very little is known about the morphology effect of CeO2 on the carbon capture and in-situ hydrogenation performance of DFMs. Here, Cu/CeO2 with different CeO2 morphologies was synthesized, and high Cu dispersion was achieved on Cu/CeO2-R, exhibiting the best CO2 hydrogenation performance. Integrated Cu/CeO2 with CaO by physical mixing method, CaO-Cu/CeO2 was used to investigate the morphology effects of CeO2 on the performance of CaO-Cu/CeO2 for integrated CO2 capture and conversion to CO. CaO-Cu/CeO2-R exhibited the best capture-hydrogenation performance (CO2 conversion rate of 75 %, CO production rate of 9.72 mmol/g). The CeO2-R provided more surface oxygen vacancies, enhancing carbonate hydrogenation. The larger specific surface area and {110} crystal plane of CeO2-rod enhanced Cu dispersion, and the smaller particle size of CeO2-R enhanced its interaction with CaO, improving the cyclic stability of CaO-Cu/CeO2-R. The hydrogenation performance of CaO-Cu/CeO2 was dependent on the morphology of CeO2, providing insights into the design of high-activity metal catalytic components in ICCC-RWGS.

Spatially asymmetrical copper dimer in ceria as an efficiently synergistic oxidation catalyst

Accurate and facile construction of atomically dispersed active sites is fundamentally important in heterogeneous catalysis. Herein, by applying a unique H2-He pretreatment, we successfully synthesize spatially asymmetrical dimeric Cu stabilized by CeO2. Integrated microscopic and spectroscopic characterizations, together with DFT calculations have revealed the redispersion of Cu species on CeO2 support is accompanied by the formation of Cu dimers with one Cu atom embedded into CeO2 lattice and the neighboring Cu atom supported on-top. The obtained dual-Cu atom catalyst demonstrates its general applicability in emission control scenarios or hydrogen fuel cell for automobile applications with excellent performances. Ab initio calculations reveal that such dimeric Cu sites on CeO2 promote reactant adsorption and lattice oxygen activation, owing to the synergistic effect of unique dimeric Cu structure. This work highlights the great potential of gas pretreatment in the fabrication of dual-atom catalysts, which is widely applicable to active site modulation in advanced oxidation catalysts.

Enhanced low-temperature CO oxidation activity through crystal facet engineering of Pd/CeO2 catalysts

Cerium dioxide (CeO2) supported palladium (Pd) catalysts have found widespread application in CO oxidation reaction owing to their exceptional catalytic performance. The morphology of the CeO2 support dictates the exposed crystal plane, exerting a profound influence on surface structure and redox properties. This is crucial as the atomic arrangement at the surface directly impacts catalytic activity. In this study, a range of CeO2 supports with diverse morphologies (e.g. nano-octahedra, nano-cubes, nano-particles, nano-spheres, and nano-rods) were successfully synthesized through hydrothermal methods and subsequently supported with Pd for CO oxidation. The spherical 1Pd/CeO2–S catalyst, revealing exposed (111) + (100) crystal planes, exhibited significantly higher CO catalytic oxidation activity compared to the catalysts with other morphological CeO2 supports. The results indicated a positive correlation between the content of PdxCe1-xO2-y species and catalytic activity. Notably, this species was most abundantly formed in the spherical 1Pd/CeO2–S catalyst with exposed (111) + (100) crystal planes. The presence of this active species facilitated the formation of surface defects, increased oxygen vacancy concentration, and enhanced metal-support interaction, consequently greatly improving the CO low-temperature catalytic oxidation activity. Consequently, the oxidation state of Pd in the Pd/CeO2 catalyst could be effectively regulated by controlling the exposure of (111) + (100) crystalline surfaces of the CeO2 support, further optimizing the catalytic performance of the Pd/CeO2 catalytic system.

Probing Pt-CeO2 interfacial interactions through adsorption characteristics of small molecules

In this study, we prepared a Pt/CeO2/Cu(111) model catalyst and investigated CO and CO2 adsorption using infrared reflection absorption spectroscopy (IRRAS) and temperature-programmed desorption (TPD) techniques to gain insight into the interaction between Pt nanoparticles and the CeO2 support surface. Our observations revealed that the deposition of CeO2 at 700 K results in island formation on the Cu(111) surface, whereas at 520 K it leads to a more continuous film formation. Reducing the CeO2/Cu(111) surface enhances the CO and CO2 uptakes on CeO2. Pt nanoparticles deposited on these surfaces remained in a metallic form, and during CO desorption, they facilitate the oxidation of CO to form CO2 by utilizing lattice oxygen from the interface between them and CeO2.

Tuning the Metal-Support Interaction by Modulating CeO2 Oxygen Vacancies to Enhance the Toluene Oxidation Activity of Pt/CeO2 Catalysts.

In this research, a range of Pt/CeO2 catalysts featuring varying Pt-O-Ce bond contents were developed by modulating the oxygen vacancies of the CeO2 support for toluene abatement. The Pt/CeO2-HA catalyst generated a maximum quantity of Pt-O-Ce bonds (possessed the strongest metal-support interaction), as evidenced by the visible Raman results, which demonstrated outstanding toluene catalytic performance. Additionally, the UV Raman results revealed that the strong metal-support interaction stimulated a substantial increase in oxygen vacancies, which could facilitate the activation of gaseous oxygen to generate abundant reactive oxygen species accumulated on the Pt/CeO2-HA catalyst surface, a conclusion supported by the H2-TPR, XPS, and toluene-TPSR results. Furthermore, the results from quasi-in situ XPS, in situ DRIFTS, and DFT indicated that the Pt/CeO2-HA catalyst with a strong metal-support interaction led to improved mobility of reactive oxygen species and lower oxygen activation energies, which could transfer a large number of activated reactive oxygen species to the reaction interface to participate in the toluene oxidation, resulting in the relatively superior catalytic performance. The approach of tuning the metal-support interaction of catalysts offers a promising avenue to develop highly active catalysts for toluene degradation.

Tailoring metal-support interactions via spatial confinement of Ni/CeO2 interfaces on h-BN for efficient CO2 methanation

Modulating metal-support interactions is critical for improving catalytic activity and product selectivity for CO2 hydrogenation. Such modulation can be achieved by modifying the metal nanoparticles as well as the supports. Here, we prepared a novel catalyst, in which Ni nanoparticles were dispersed on CeO2 and hexagonal boron nitride (h-BN) hybrid supports. The introduction of h-BN to Ni/CeO2-BN effectively improves the dispersion of Ni nanoparticles. More importantly, the abundant Ni-CeO2 interfacial sites with enriched oxygen vacancies are formed over h-BN edge sites. The dispersed Ni species are anchored on CeO2 via a unique interfacial structure, with electron-rich Ni (Niδ−) species. At the interfacial sites on Ni/CeO2-BN, the synergy between oxygen vacancies and Niδ−, which enhances CO2 activation and H2 dissociation, respectively, renders superior catalytic performance for CO2 methanation. In situ DRIFTS suggests formate as key rate-limiting intermediates on Ni-CeO2 sites, while the formation of B-H bonds further promotes hydrogen activation and subsequently the catalytic performance. The modulation of metal-support interactions by spatial confinement effect by BN offers a new paradigm for designing metal/oxide catalysts for chemical transformations that requires bifunctionality as CO2 hydrogenation.

Zn doped CeO2 supporting Ni–Pt catalysts toward robust hydrogen generation from hydrous hydrazine

Ni-based bimetallic catalysts with noble metals exhibit high activity and selectivity for hydrogen generation from hydrazine monohydrate. However, their poor service durability remains a critical challenge. This study investigated the use of Zn-doped CeO2 as a support for Ni–Pt catalysts to improve their long-term stability. A series of Ni–Pt/Zn-doped-CeO2 catalysts were prepared via a simple co-precipitation and reduction method. Compared to the pristine Ni50Pt50/CeO2 catalyst, the Zn doping can improve the stability of CeO2 support in the alkaline condition, and the X-ray photoelectron spectroscopy (XPS) analysis clearly indicates that Zn doping leads to a negative shift in the binding energy of connected Ni and thus enhances the stability of the electronic structure in the catalysts. The findings in this work suggest that Zn-modified CeO2 supporting Ni–Pt catalyst offer a promising approach to achieving a better balance between activity and durability for hydrogen generation catalysts.

Reduction of (100)-Faceted CeO2 for Effective Pt Loading.

Although the function and stability of catalysts are known to significantly depend on their dispersion state and support interactions, the mechanism of catalyst loading has not yet been elucidated. To address this gap in knowledge, this study elucidates the mechanism of Pt loading based on a detailed investigation of the interaction between Pt species and localized polarons (Ce3+) associated with oxygen vacancies on CeO2(100) facets. Furthermore, an effective Pt loading method was proposed for achieving high catalytic activity while maintaining the stability. Enhanced dispersibility and stability of Pt were achieved by controlling the ionic interactions between dissolved Pt species and CeO2 surface charges via pH adjustment and reduction pretreatment of the CeO2 support surface. This process resulted in strong interactions between Pt and the CeO2 support. Consequently, the oxygen-carrier performance was improved for CH4 chemical looping reforming reactions. This simple interaction-based loading process enhanced the catalytic performance, allowing the efficient use of noble metals with high performance and small loading amounts.

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.

Highly active CeO2-CuCo nanoparticles supported on hollow N-doped carbon spheres for boosting ammonia borane hydrolysis and tandem 4-nitrophenol reduction reactions

It’s a safe method to use high hydrogen density ammonia borane (AB) to facilitate the tandem hydrogenation of aromatic nitro compounds. While a major problem for tandem hydrogenation, the development of non-noble metal catalysts with high activity and stability is encouraging. This work involved the synthesis of highly active CeO2/CuCo nanoparticles support on hollow N-doped carbon spheres and its investigation for AB hydrolysis, taking into account the impacts of the HNCSs and CeO2 supports. Because CuCo alloy, CeO2, and HNCSs supports worked in concert, HNCSs@CeO2/CuCo was found to be the best catalyst. The activation energy achieved was comparable to the reported Pd- and Pt-based catalysts, with a value as low as 21.8 kJ/mol. Using AB as the in-situ H2 source, HNCSs@CeO2/CuCo exhibited a significant degree of activity in the one-pot tandem reduction of 4-NP with the turnover frequency of 2830.2 h−1, even surpassing over ten times of some noble metal catalysts. Following five consecutive cycles of reaction condition tuning, the HNCSs@CeO2/CuCo catalyst demonstrated a constant conversion efficiency. Also, the catalyst's uses for one-pot tandem reduction of other highly active aromatic nitro compounds were expanded.