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1.
Xuan Zhou Kai Li Yunxiang Lin Li Song Jincheng Liu Yu Liu Lingling Zhang Zhijian Wu Shuyan Song Jun Li Hongjie Zhang 《Angewandte Chemie (International ed. in English)》2020,59(32):13568-13574
Synthesis of well‐defined atomically mixed alloy nanoparticles on desired substrates is an ultimate goal for their practical application. Herein we report a general approach for preparing atomically mixed AuPt, AuPd, PtPd, AuPtPd NAs(nanoalloys) through single‐atom level manipulation. By utilizing the ubiquitous tendency of aggregation of single atoms into nanoparticles at elevated temperatures, we have synthesized nanoalloys on a solid solvent with CeO2 as a carrier and transition‐metal single atoms as an intermediate state. The supported nanoalloys/CeO2 with ultra‐low noble metal content (containing 0.2 wt % Au and 0.2 wt % Pt) exhibit enhanced catalytic performance towards complete CO oxidation at room temperature and remarkable thermostability. This work provides a general strategy for facile and rapid synthesis of well‐defined atomically mixed nanoalloys that can be applied for a range of emerging techniques. 相似文献
2.
Revealing the Active Species for Aerobic Alcohol Oxidation by Using Uniform Supported Palladium Catalysts 下载免费PDF全文
Pingyu Xin Prof. Dr. Jia Li Yu Xiong Xi Wu Dr. Juncai Dong Dr. Wenxing Chen Prof. Dr. Yu Wang Prof. Dr. Lin Gu Prof. Dr. Jun Luo Dr. Hongpan Rong Prof. Dr. Chen Chen Prof. Dr. Qing Peng Prof. Dr. Dingsheng Wang Prof. Dr. Yadong Li 《Angewandte Chemie (International ed. in English)》2018,57(17):4642-4646
The active species in supported metal catalysts are elusive to identify, and large quantities of inert species can cause significant waste. Herein, using a stoichiometrically precise synthetic method, we prepare atomically dispersed palladium–cerium oxide (Pd1/CeO2) and hexapalladium cluster–cerium oxide (Pd6/CeO2), as confirmed by spherical‐aberration‐corrected transmission electron microscopy and X‐ray absorption fine structure spectroscopy. For aerobic alcohol oxidation, Pd1/CeO2 shows extremely high catalytic activity with a TOF of 6739 h?1 and satisfactory selectivity (almost 100 % for benzaldehyde), while Pd6/CeO2 is inactive, indicating that the true active species are single Pd atoms. Theoretical simulations reveal that the bulkier Pd6 clusters hinder the interactions between hydroxy groups and the CeO2 surface, thus suppressing synergy of Pd‐Ce perimeter. 相似文献
3.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(31):9114-9119
Ceria (CeO2) supports are unique in their ability to trap ionic platinum (Pt), providing exceptional stability for isolated single atoms of Pt. The reactivity and stability of single‐atom Pt species was explored for the industrially important light alkane dehydrogenation reaction. The single‐atom Pt/CeO2 catalysts are stable during propane dehydrogenation, but are not selective for propylene. DFT calculations show strong adsorption of the olefin produced, leading to further unwanted reactions. In contrast, when tin (Sn) is added to CeO2, the single‐atom Pt catalyst undergoes an activation phase where it transforms into Pt–Sn clusters under reaction conditions. Formation of small Pt–Sn clusters allows the catalyst to achieve high selectivity towards propylene because of facile desorption of the product. The CeO2‐supported Pt–Sn clusters are very stable, even during extended reaction at 680 °C. Coke formation is almost completely suppressed by adding water vapor to the feed. Furthermore, upon oxidation the Pt–Sn clusters readily revert to the atomically dispersed species on CeO2, making Pt–Sn/CeO2 a fully regenerable catalyst. 相似文献
4.
Dr. Haifeng Xiong Dr. Sen Lin Joris Goetze Dr. Paul Pletcher Prof. Dr. Hua Guo Dr. Libor Kovarik Dr. Kateryna Artyushkova Prof. Dr. Bert M. Weckhuysen Prof. Dr. Abhaya K. Datye 《Angewandte Chemie (International ed. in English)》2017,56(31):8986-8991
Ceria (CeO2) supports are unique in their ability to trap ionic platinum (Pt), providing exceptional stability for isolated single atoms of Pt. The reactivity and stability of single-atom Pt species was explored for the industrially important light alkane dehydrogenation reaction. The single-atom Pt/CeO2 catalysts are stable during propane dehydrogenation, but are not selective for propylene. DFT calculations show strong adsorption of the olefin produced, leading to further unwanted reactions. In contrast, when tin (Sn) is added to CeO2, the single-atom Pt catalyst undergoes an activation phase where it transforms into Pt–Sn clusters under reaction conditions. Formation of small Pt–Sn clusters allows the catalyst to achieve high selectivity towards propylene because of facile desorption of the product. The CeO2-supported Pt–Sn clusters are very stable, even during extended reaction at 680 °C. Coke formation is almost completely suppressed by adding water vapor to the feed. Furthermore, upon oxidation the Pt–Sn clusters readily revert to the atomically dispersed species on CeO2, making Pt–Sn/CeO2 a fully regenerable catalyst. 相似文献
5.
Jing Xu Ying Wang Ke Wang Meng Zhao Rui Zhang Wenjie Cui Li Liu Dr. Megalamane S. Bootharaju Dr. Jeong Hyun Kim Prof. Taeghwan Hyeon Prof. Hongjie Zhang Prof. Yu Wang Prof. Shuyan Song Prof. Xiao Wang 《Angewandte Chemie (International ed. in English)》2023,62(28):e202302877
Reducible oxide-supported noble metal nanoparticles exhibit high activity in catalyzing many important oxidation reactions. However, atom migration under harsh reaction conditions leads to deactivation of the catalyst. Meanwhile, single-atom catalysts demonstrate enhanced stability, but often suffer from poor catalytic activity owing to the ionized surface states. In this work, we simultaneously address the poor activity and stability issues by synthesizing highly active and durable rhodium (Rh) single-atom catalysts through a “wrap-bake-peel” process. The pre-coated SiO2 layer during synthesis of catalyst plays a crucial role in not only protecting CeO2 support against sintering, but also donating electron to weaken the Ce−O bond, producing highly loaded Rh single atoms on the CeO2 support exposed with high-index {210} facets. Benefiting from the unique electronic structure of CeO2 {210} facets, more oxygen vacancies are generated along with the deposition of more electropositive Rh single atoms, leading to remarkably improved catalytic performance in CO oxidation. 相似文献
6.
Analysis of Dopant Atom Distribution and Quantification of Oxygen Vacancies on Individual Gd‐Doped CeO2 Nanocrystals 下载免费PDF全文
Dr. Daniel G. Stroppa Prof. Cleocir J. Dalmaschio Dr. Lothar Houben Dr. Juri Barthel Prof. Luciano A. Montoro Prof. Edson R. Leite Dr. Antonio J. Ramirez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(21):6288-6293
This work reports the analysis of the distribution of Gd atoms and the quantification of O vacancies applied to individual CeO2 and Gd‐doped CeO2 nanocrystals by electron energy‐loss spectroscopy. The concentration of O vacancies measured on the undoped system (6.3±2.6 %) matches the expected value given the typical Ce3+ content previously reported for CeO2 nanoparticles. The doped nanoparticles have an uneven distribution of dopant atoms and an atypical amount of O vacant sites (37.7±4.1 %). The measured decrease of the O content induced by Gd doping cannot be explained solely by the charge balance including Ce3+ and Gd3+ ions. 相似文献
7.
Maximum Noble‐Metal Efficiency in Catalytic Materials: Atomically Dispersed Surface Platinum 下载免费PDF全文
Dr. Albert Bruix Dr. Yaroslava Lykhach Dr. Iva Matolínová M. Sc. Armin Neitzel Dr. Tomáš Skála Dr. Nataliya Tsud Dr. Mykhailo Vorokhta M. Sc. Vitalii Stetsovych M. Sc. Klára Ševčíková Dr. Josef Mysliveček M. Sc. Roman Fiala M. Sc. Michal Václavů Dr. Kevin C. Prince Dr. Stéphanie Bruyère Dr. Valérie Potin Prof. Dr. Francesc Illas Prof. Dr. Vladimír Matolín Prof. Dr. Jörg Libuda Prof. Dr. Konstantin M. Neyman 《Angewandte Chemie (International ed. in English)》2014,53(39):10525-10530
Platinum is the most versatile element in catalysis, but it is rare and its high price limits large‐scale applications, for example in fuel‐cell technology. Still, conventional catalysts use only a small fraction of the Pt content, that is, those atoms located at the catalyst’s surface. To maximize the noble‐metal efficiency, the precious metal should be atomically dispersed and exclusively located within the outermost surface layer of the material. Such atomically dispersed Pt surface species can indeed be prepared with exceptionally high stability. Using DFT calculations we identify a specific structural element, a ceria “nanopocket”, which binds Pt2+ so strongly that it withstands sintering and bulk diffusion. On model catalysts we experimentally confirm the theoretically predicted stability, and on real Pt‐CeO2 nanocomposites showing high Pt efficiency in fuel‐cell catalysis we also identify these anchoring sites. 相似文献
8.
Konstantin Khivantsev Carlos Garcia Vargas Jinshu Tian Libor Kovarik Nicholas R. Jaegers Janos Szanyi Yong Wang 《Angewandte Chemie (International ed. in English)》2021,60(1):391-398
We show for the first time that atomically dispersed Rh cations on ceria, prepared by a high‐temperature atom‐trapping synthesis, are the active species for the (CO+NO) reaction. This provides a direct link with the organometallic homogeneous RhI complexes capable of catalyzing the dry (CO+NO) reaction. The thermally stable Rh cations in 0.1 wt % Rh1/CeO2 achieve full NO conversion with a turn‐over‐frequency (TOF) of around 330 h?1 per Rh atom at 120 °C. Under dry conditions, the main product above 100 °C is N2 with N2O being the minor product. The presence of water promotes low‐temperature activity of 0.1 wt % Rh1/CeO2. In the wet stream, ammonia and nitrogen are the main products above 120 °C. The uniformity of Rh ions on the support, allows us to detect the intermediates of (CO+NO) reaction via IR measurements on Rh cations on zeolite and ceria. We also show that NH3 formation correlates with the water gas shift (WGS) activity of the material and detect the formation of Rh hydride species spectroscopically. 相似文献
9.
Anees A. Ansari J. Labis Manawwer Alam Shahid M. Ramay Naushad Ahmad Asif Mahmood 《中国化学会会志》2015,62(10):925-932
We report the structural, thermal, optical, and redox properties of Fe‐doped cerium oxide (CeO2) nanoparticles, obtained using the polyol‐co‐precipitation process. X‐ray diffraction data reveal the formation of single‐phase structurally isomorphous CeO2. The presence of Fe3+ may act as electron acceptor and/or hole donor, facilitating longer lived charge carrier separation in Fe‐doped CeO2 nanoparticles as confirmed by optical band gap energy. The increased content of localized defect states in the ceria gap and corresponding shift of the optical absorption edge towards visible range in Fe‐doped samples can significantly improve the optical activity of nanocrystalline ceria. The better‐quality redox performances of the Fe‐doped CeO2 nanoparticles, compared with undoped CeO2 nanoparticles, were ascribed mainly to a decrease in band gap energy and an increase in specific surface area of the material. As observed from TPR studies all Fe ‐doped CeO2 nanoparticles, particularly the 10 mol % Fe doped CeO2 nanoproduct, exhibit excellent reduction performance. 相似文献
10.
Dr. Qin Wang Dr. Wenjing Jia Dr. Baocang Liu Prof. Dr. Wenzhi Zhao Dr. Changyan Li Prof. Dr. Jun Zhang Prof. Dr. Gang Xu 《化学:亚洲杂志》2012,7(10):2258-2267
Herein, we report a facile surfactant‐assisted solvothermal synthetic method to prepare nearly monodisperse spherical CeO2 nanocrystals. A good control of the size of CeO2 nanocrystals in the range of 100–500 nm was achieved by simply varying the synthetic parameters such as reaction time, volume ratio of ethanol to water (R), molar ratio of PVP, and concentration of Ce(NO3)3?6 H2O in solution. A possible mechanism for the growth of spherical CeO2 nanocrystals is proposed. The obtained CeO2 nanocrystals with a surface area of up to 47 m2g?1 were then employed as a catalyst support. By loading Au‐Pd nanoparticles (about 3 wt. %) onto the CeO2 support, an Au‐Pd/CeO2 catalyst was prepared that exhibited high catalytic activity for HCHO oxidation. At the low temperature of 50 °C, the percentage of HCHO conversion was 100 %, suggesting potential applications in preferential oxidation and other catalytic reactions. These Au‐Pd/CeO2 catalysts may also find applications in indoor formaldehyde decontamination and industrial catalysis. The facile solvothermal method can be extended to the preparation of other metal oxide nanocrystals and provides guidance for size‐ and morphology‐controlled synthesis. 相似文献
11.
Dilan Karapinar Ngoc Tran Huan Nastaran Ranjbar Sahraie Jingkun Li David Wakerley Nadia Touati Sandrine Zanna Dario Taverna Luiz Henrique Galvo Tizei Andrea Zitolo Frdric Jaouen Victor Mougel Marc Fontecave 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(42):15242-15247
It is generally believed that CO2 electroreduction to multi‐carbon products such as ethanol or ethylene may be catalyzed with significant yield only on metallic copper surfaces, implying large ensembles of copper atoms. Here, we report on an inexpensive Cu‐N‐C material prepared via a simple pyrolytic route that exclusively feature single copper atoms with a CuN4 coordination environment, atomically dispersed in a nitrogen‐doped conductive carbon matrix. This material achieves aqueous CO2 electroreduction to ethanol at a Faradaic yield of 55 % under optimized conditions (electrolyte: 0.1 m CsHCO3, potential: ?1.2 V vs. RHE and gas‐phase recycling set up), as well as CO electroreduction to C2‐products (ethanol and ethylene) with a Faradaic yield of 80 %. During electrolysis the isolated sites transiently convert into metallic copper nanoparticles, as shown by operando XAS analysis, which are likely to be the catalytically active species. Remarkably, this process is reversible and the initial material is recovered intact after electrolysis. 相似文献
12.
Silver Nanoparticles Supported on CeO2‐SBA‐15 by Microwave Irradiation Possess Metal–Support Interactions and Enhanced Catalytic Activity 下载免费PDF全文
Dr. Xufang Qian Prof. Dr. Yasutaka Kuwahara Prof. Dr. Kohsuke Mori Prof. Dr. Hiromi Yamashita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(48):15746-15752
Metal–support interactions (MSIs) and particle size play important roles in catalytic reactions. For the first time, silver nanoparticles supported on CeO2‐SBA‐15 supports are reported that possess tunable particle size and MSIs, as prepared by microwave (MW) irradiation, owing to strong charge polarization of CeO2 clusters (i.e., MW absorption). Characterizations, including TEM, X‐ray photoelectron spectroscopy, and extended X‐ray absorption fine structure, were carried out to disclose the influence of CeO2 contents on the Ag particle size, MSI effect between Ag nanoparticles and CeO2‐SBA‐15 supports, and the strong MW absorption of CeO2 clusters that contribute to the MSIs during Ag deposition. The Ag particle sizes were controllably tuned from 1.9 to 3.9 nm by changing the loading amounts of CeO2 from 0.5 to 2.0 wt %. The Ag nanoparticle size was predominantly responsible for the high turnover frequency (TOF) of 0.41 min?1 in ammonia borane dehydrogenation, whereas both particle size and MSIs contributed to the high TOF of 555 min?1 in 4‐nitrophenol reduction for Ag/0.5CeO2‐SBA‐15, which were twice as large as those of Ag/SBA‐15 without CeO2 and Ag/CeO2‐SBA‐15 prepared by conventional oil‐bath heating. 相似文献
13.
Changqing Li 《Journal of solid state chemistry》2008,181(10):2620-2625
We report a method to prepare composites based on carbon nanotubes (CNTs) and CeO2 nanoparticles (NPs). The CeO2 NPs were attached to CNTs by hydrothermal treatment of Ce(OH)4/CNT mixture in NaOH solution at 180 °C. It was found that larger CeO2 NPs were formed in the presence of CNTs. Grain size of CeO2 NPs in the composites can be reduced when NaNO3 was added in the hydrothermal process. Electrochemical characterizations have shown that the composites possess a specific capacity between those of CNTs and CNTs mechanically mixed with CeO2. These CeO2/CNT composites could serve as promising anode materials for Li-ion batteries. 相似文献
14.
Dr. Irene Vassalini Dr. Laura Borgese Michele Mariz Prof. Stefano Polizzi Dr. Giuliana Aquilanti Prof. Paolo Ghigna Prof. Andrea Sartorel Prof. Vincenzo Amendola Prof. Ivano Alessandri 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6689-6693
Oxygen evolution reaction (OER) is the most critical step in water splitting, still limiting the development of efficient alkaline water electrolyzers. Here we investigate the OER activity of Au–Fe nanoalloys obtained by laser-ablation synthesis in solution. This method allows a high amount of iron (up to 11 at %) to be incorporated into the gold lattice, which is not possible in Au–Fe alloys synthesized by other routes, due to thermodynamic constraints. The Au0.89Fe0.11 nanoalloys exhibit strongly enhanced OER in comparison to the individual pure metal nanoparticles, lowering the onset of OER and increasing up to 20 times the current density in alkaline aqueous solutions. Such a remarkable electrocatalytic activity is associated to nanoalloying, as demonstrated by comparative examples with physical mixtures of gold and iron nanoparticles. These results open attractive scenarios to the use of kinetically stable nanoalloys for catalysis and energy conversion. 相似文献
15.
S. N. Lanin A. A. Bannykh A. E. Vinogradov N. V. Kovaleva K. S. Lanina S. A. Nikolaev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(7):1427-1433
The adsorption properties of nanocomposites based on γ-Al2O3 modified with CeOx, Au/CeOx, and Pd/CeOx nanoparticles with contents of deposited metals ranging from 0.07 to 1.71 wt % are investigated by means of dynamic sorption method. n-Alkanes (C6–C8), acetonitrile, diethyl ether, tetrahydrofuran, and dioxane are used as test adsorbates. Adsorption isotherms are measured, and the isosteric heats of adsorption of a number of test adsorbates are calculated. Electron-donor and electron-acceptor characteristics of the surfaces of γ-Al2O3-based nanocomposites are estimated. It is shown that Au(0.1%)/CeOx(0.07%)/γ-Al2O3 nanocomposite, which has the lowest content of nanoparticles of the deposited metals, has the highest adsorption activity. 相似文献
16.
Dr. Xiang Li Dr. Annette-Enrica Surkus Dr. Jabor Rabeah Dr. Muhammad Anwar Dr. Sarim Dastigir Dr. Henrik Junge Prof. Dr. Angelika Brückner Prof. Dr. Matthias Beller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):15983-15988
Metal–organic framework (MOF)-derived Co-N-C catalysts with isolated single cobalt atoms have been synthesized and compared with cobalt nanoparticles for formic acid dehydrogenation. The atomically dispersed Co-N-C catalyst achieves superior activity, better acid resistance, and improved long-term stability compared with nanoparticles synthesized by a similar route. High-angle annular dark-field–scanning transmission electron microscopy, X-ray photoelectron spectroscopy, electron paramagnetic resonance, and X-ray absorption fine structure characterizations reveal the formation of CoIINx centers as active sites. The optimal low-cost catalyst is a promising candidate for liquid H2 generation. 相似文献
17.
A. A. Firsova A. N. Il’ichev T. I. Khomenko L. V. Gorobinskii Yu. V. Maksimov I. P. Suzdalev V. N. Korchak 《Kinetics and Catalysis》2007,48(2):282-291
The selective oxidation of CO in the presence of hydrogen on CuO/CeO2 systems containing Fe and Ni oxides as promoters was studied. The catalysts containing 1–5 wt % CuO and 1–2.5 wt % Fe2O3 supported on CeO2 and the CuO/CeO2 systems containing 1–2.5 wt % NiO were synthesized, and their catalytic activity as a function of temperature was determined. It was found that the additives of Fe and Ni oxides increased the activity of the CuO/CeO2 catalysts with a low concentration of CuO. In this case, the conversion of CO at 150°C approached 100%. At the same time, these additives had no effect on the activity of the CuO/CeO2 systems at a CuO concentration of 5 wt % or higher, which exhibited an initially high activity in the above temperature region. The forms of CO adsorption and the amounts of active sites for CO adsorption and oxidation were studied using temperature-programmed desorption. It was found that the introduction of Fe and Ni additives in a certain preparation procedure facilitated the formation of an additional amount of active centers associated with CuO. Data on the temperature-programmed reduction of samples (the amount of absorbed hydrogen and the maximum temperature of hydrogen absorption) suggested the interaction of all catalyst components, and the magnitude of this interaction depended on the sample preparation procedure. With the use of Mössbauer spectroscopy, it was found that the procedure of iron oxide introduction into the CuO/CeO2 system was responsible for the electron-ion interactions of catalyst components and the reaction mixture. 相似文献
18.
Yongchun Xiao Kui Xie 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2022,134(1):e202113079
Dry reforming of CH4/CO2 provides an attractive route to convert greenhouse gas into syngas; however, the resistance to sintering and coking of catalyst remains a fundamental challenge at high operation temperatures. Here we create active and durable metal–oxide interfaces in porous single-crystalline (PSC) CeO2 monoliths with in situ exsolved single-crystalline (SC) Ni particles and show efficient dry reforming of CH4/CO2 at temperatures as low as 450 °C. We show the excellent and durable performance with ≈20 % of CH4 conversion and ≈30 % of CO2 conversion even in a continuous operation of 240 hours. The well-defined active metal–oxide interfaces, created by exsolving SC Ni nanoparticles from PSC NixCe1?xO2 to anchor them on PSC CeO2 scaffolds, prevent nanoparticle sintering and enhance the coking resistance due to the stronger metal–support interactions. Our work would enable an industrially and economically viable path for carbon reclamation, and the technique of creating active and durable metal–oxide interfaces in PSC monoliths could lead to stable catalyst designs for many challenging reactions. 相似文献
19.
Kaiser J Leppert L Welz H Polzer F Wunder S Wanderka N Albrecht M Lunkenbein T Breu J Kümmel S Lu Y Ballauff M 《Physical chemistry chemical physics : PCCP》2012,14(18):6487-6495
We present a quantitative study of the catalytic activity of well-defined faceted gold-palladium nanoalloys which are immobilized on cationic spherical polyelectrolyte brushes. The spherical polyelectrolyte brush particles used as carriers for the nanoalloys consist of a solid polystyrene core onto which cationic polyelectrolyte chains of 2-aminoethyl methacrylate are attached. Au/Pd nanoalloy particles with sizes in the range from 1 to 3 nm have been generated which are homogeneously distributed on the surface of the spherical polyelectrolyte brushes. The reduction of 4-nitrophenol has been chosen as a well-controlled model reaction allowing us to determine the catalytic activity of the nanoalloys as a function of the Au/Pd composition. The adsorption behavior was studied by Langmuir-Hinshelwood kinetics. We find a pronounced maximum of the catalytic activity at 75 molar % Au. A comparison of gold, platinum, palladium and gold-palladium alloy nanoparticles is made in terms of Langmuir-Hinshelwood kinetics. Density functional calculations for Au/Pd clusters with up to 38 atoms show that the density of states at the Fermi level increases with increasing Pd content, and that the highest occupied orbitals are associated with Pd atoms. The calculations confirm that small changes in the atomic arrangement can lead to pronounced changes in the particles' electronic properties, indicating that the known importance of surface effects is further enhanced in nanoalloys. 相似文献
20.
Ying Xue Yanwu Zhai Prof. Dr. Kebin Zhou Lei Wang Haina Tan Qingfen Luan Prof. Dr. Xin Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(35):11115-11122
Cerium oxide (CeO2) nanoparticles display excellent antioxidant properties by scavenging free radicals. However, some studies have indicated that they can cause an adverse response by generating reactive oxygen species (ROS). Hence, it is important to clarify the factors that affect the oxidant/antioxidant activities of CeO2 nanoparticles. In this work, we report the effects of different buffer anions on the antioxidant activity of CeO2 nanoparticles. Considering the main anions present in the body, Tris‐HCl, sulfate, and phosphate buffer solutions have been used to evaluate the antioxidant activity of CeO2 nanoparticles by studying their DNA protective effect. The results show that CeO2 nanoparticles can protect DNA from damage in Tris‐HCl and sulfate systems, but not in phosphate buffer solution (PBS) systems. The mechanism of action has been explored: cerium phosphate is formed on the surface of the nanoparticles, which interferes with the redox cycling between Ce3+ and Ce4+. As a result, the antioxidant activity of CeO2 nanoparticles is greatly affected by the external environment, especially the anions. These results may provide guidance for the further practical application of CeO2 nanoparticles. 相似文献