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Mastering the surface strain of platinum catalysts for efficient electrocatalysis


Platinum (Pt) has found wide use as an electrocatalyst for sustainable energy conversion systems1,2,3. The activity of Pt is controlled by its electronic structure (typically, the d-band centre), which depends sensitively on lattice strain4,5. This dependence can be exploited for catalyst design4,6,7,8, and the use of core–shell structures and elastic substrates has resulted in strain-engineered Pt catalysts with drastically improved electrocatalytic performances7,9,10,11,12,13. However, it is challenging to map in detail the strain–activity correlations in Pt-catalysed conversions, which can involve a number of distinct processes, and to identify the optimal strain modification for specific reactions. Here we show that when ultrathin Pt shells are deposited on palladium-based nanocubes, expansion and shrinkage of the nanocubes through phosphorization and dephosphorization induces strain in the Pt(100) lattice that can be adjusted from −5.1 per cent to 5.9 per cent. We use this strain control to tune the electrocatalytic activity of the Pt shells over a wide range, finding that the strain–activity correlation for the methanol oxidation reaction and hydrogen evolution reaction follows an M-shaped curve and a volcano-shaped curve, respectively. We anticipate that our approach can be used to screen out lattice strain that will optimize the performance of Pt catalysts—and potentially other metal catalysts—for a wide range of reactions.

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Fig. 1: Schematic of the lattice strain control of ultrathin Pt shells deposited on Pd-based nanocubes.
Fig. 2: Characterizations of unstrained and tensile-strained Pt shells.
Fig. 3: Characterizations of compressive strained Pt shells.
Fig. 4: Electrochemical characterization.
Fig. 5: DFT calculations.

Data availability

The data that support the findings of this study are available from the corresponding authors upon reasonable request. Source data are provided with this paper.

Code availability

The Vienna ab initio Simulation Package (VASP) for the density functional theory calculations is available at


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We thank J. Li, C. Li, J. Liu and G. Zhou at the Instrument Analysis Center in Xi’an Jiaotong University for assistance with HRTEM, XPS and ICP-MS analyses. We acknowledge the support from the Shanghai Institute of Microsystem and Information Technology for HAADF-STEM characterizations. The work is sponsored by the National Natural Science Foundation of China (NSFC, numbers 51888103, 21773180, 21875137, 51521004 and 5140105009), the State Key Laboratory for Mechanical Behavior of Materials from Xi’an Jiaotong University, the National Key R&D Program of China (number 2017YFB0406000) and the Center of Hydrogen Science and Joint Research Center for Clean Energy Materials from Shanghai Jiao Tong University. Y.Y. acknowledges the support from UC Riverside and Korea Institute of Materials Science through the UC-KIMS Center for Innovation Materials for Energy and Environment and the Hydrogen Energy Innovation Technology Development Program of the National Research Foundation of Korea (NRF) funded by the Korean government (Ministry of Science and ICT (MSIT); grant NRF-2019M3E6A1064020).

Author information




M.J. and Y.Y. conceived and designed the experiments. T.H. and W.W. performed the catalyst preparation, catalytic testing, characterization and wrote the manuscript. F.S. and J.W. contributed to the geometric phase analysis and HAADF-STEM analysis. X.Y. carried out theoretical calculations for this work. X.L. participated in the data analysis on electrocatalysis. The manuscript was written through the contributions of all authors.

Corresponding authors

Correspondence to Jianbo Wu, Yadong Yin or Mingshang Jin.

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The authors declare no competing interests.

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Peer review information Nature thanks Sylvain Brimaud and Harry Hoster for their contribution to the peer review of this work. Peer reviewer reports are available.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data figures and tables

Extended Data Fig. 1 Key characteristics of the synthesis.

af, TEM images of Pd nanocubes phosphorized for 0 min (a), 2.5 min (b), 5 min (c), 7.5 min (d), 10 min (e) and 20 min (f). The interfaces between inner Pd cores and outer Pd-P phase are marked with white boxes for better comparison among all samples. The magnifications of inset images are the same as other particles. g, h, Representative STEM images of the uniform PtC-2.5 (g) and PtT-2.8 (h) core-shell nanocubes. i, Atomic ratio of Pt:Pd calculated from the ICP-MS data and the number of Pt atomic layers, suggesting an average thickness of ~7 atomic layers for all Pt shells. jm, Representative HRTEM image (j, k), HAADF-STEM (l) image, and lattice profile (m) of Pt shell grown on Pd@Pd-P seed. The Pd/Pd-P interphase and Pd-P/Pt interface are marked with white boxes for better observation.

Extended Data Fig. 2 Characterization of the lattice strain in Pt shells.

ac, Lattice profiles measured at different regions in PtT-1.3 (a), PtT-2.8 (b) and PtT-5.9 (c), showing the uniform strain distributions. d, Average lattice strains of tensile strained samples calculated from the value collected from the edge sites. e, f, HAADF-STEM images of overly phosphorized Pd-P@Pt nanocubes, showing the significant rupture of the Pt shell. gi, HRTEM images of Pd@Pt nanocubes (g) and Pd-P@Pt nanocubes (h), and their XRD patterns showing negative shifts for the diffraction peaks of Pd-P@Pt relative to those of Pd@Pt nanocubes (i). jl, Lattice profiles measured at different regions in PtC-1.2 (j), PtC-2.5 (k) and PtC-5.1 (l). m, Average lattice strains of compressive strained samples calculated from the value collected from the shell regions. n, o, XPS spectrum of tensile strained Pt shells (n) and compressive strained Pt shells (o), showing that the Pt binding energy shifts negatively with the lattice expanding and positively with the lattice contracting. p, ICP-MS-determined content of Pd and P for different samples (C-xP represents Pd-P@Pt prior to the dephosphorization), verifying the complete removal of P during the dephosphorization process.

Extended Data Fig. 3 Characterization of the surface compositions of PtC-2.5.

af, Layer-by-layer EDX line scan analysis for a single particle. gm, Representative STEM image of Pt0 (g) and layer-by-layer EDX line scans for particles in the recorded region (hm). These data demonstrate the low-level Pd/Pt intermixing on the surface of compressive strained Pt (100) shells.

Extended Data Fig. 4 Characterization of the surface compositions of Pt0.

af, Layer-by-layer EDX line scan analysis for a single particle. go, Representative STEM image of PtC-2.5 (g) and layer-by-layer EDX line scans for particles in the recorded region (ho). These data demonstrate the low-level Pd/Pt intermixing on the surface of non-strained Pt (100) shells.

Extended Data Fig. 5 Characterization of the surface compositions of PtT-2.8.

af, Layer-by-layer EDX line scan analysis for a single particle. gn, Representative STEM image of PtT-2.8 (g, k) and layer-by-layer EDX line scans for particles in the recorded region (hj, ln). These data demonstrate the low-level Pd/Pt intermixing on the surface of tensile-strained Pt (100) shells.

Extended Data Fig. 6 Structural analyses of Pt shells before and after electrocatalysis.

ac, TEM images, HAADF-STEM images, and lattice profiles of PtC-5.1 (a), Pt0 (b) and PtT-5.9 (c), showing negligible restructuring of the core-shell catalysts after MOR catalysis. d, Proportions of different types of surface defects (Pt (111) sites and step sites) calculated by counting the atomic numbers of different sites on all Pt surfaces before (d2) MOR catalysis and proportions of different types of surface defects of PtC-5.1, Pt0, PtT-5.9 (from left to right) after (d3) MOR catalysis, showing the identically minor fractions of defects on all Pt shells and negligible accumulation of these defects during electrocatalysis. em, CV curves of the strain-modified Pt shells before and after MOR catalysis, showing no obvious restructuring of Pt (100) surfaces. n, CV curve of Pt/C catalyst. o, ECSAs of all catalysts. The error bars in d2, d3 and o represent the standard deviations of five independent measurements of the same sample.

Extended Data Fig. 7 Electrocatalytic properties of all catalysts.

MOR specific and mass activities at 0.65 V (a, b) and i-t curves recorded at 0.65 V (c) and 0.3 V (d), all measured vs. Ag/AgCl in a solution containing 0.5 M H2SO4 and 1 M CH3OH. The initial specific MOR activities of all catalysts at 0.65 V vs. Ag/AgCl (e) and 0.3 V vs. Ag/AgCl (f); and the corresponding steady specific activities of all catalysts at the end of the i-t recording at 0.65 V vs. Ag/AgCl 0(g) and 0.3 V vs. Ag/AgCl (h). CO stripping tests (i, j) show that CO can be oxidized at a lower potential on compressive strained Pt while at a higher potential on tensile strained Pt. HER polarization curves (kn) and HER specific and mass catalytic activities at −0.07 V vs. RHE (o, p) for all catalysts measured in 1 M KOH. Fitting of the HER polarization curves based on Butler-Volmer equation (q, r) gives Tafel slope values and exchange current densities of all catalysts toward HER (s). The error bars in a, b, eh, o and p represent the standard deviations of five independent measurements of the same sample.

Extended Data Fig. 8 DFT calculations.

a, Atomic models showing the different adsorption sites on Pt (100) surface. b, c, Strain-dependent reaction free energies of water dissociation in alkaline (b) and acidic (c) solutions. df, Strain-dependent adsorption energies of OH* (d), H* (e) and CO* (f) on different sites.

Extended Data Fig. 9 Comparisons of catalytic performances.

a, MOR catalytic activities (at ~0.65 V vs. Ag/AgCl) achieved by some typical Pt-based catalysts developed in recent years. b, HER catalytic activities (at −0.07 V vs. Ag/AgCl) achieved by some typical Pt-based catalysts developed in recent years. c, MOR catalytic activities (at ~0.65 V versus Ag/AgCl) achieved by some typical PdPt bimetallic catalysts developed in recent years. d, Representative TEM image of Pd@Pt core-shell nanocubes synthesized using ~6 nm Pd nanocubes instead of ~17.3 nm Pd nanocubes as substrates.

Extended Data Fig. 10 Characterization of catalytic stabilities.

ad, MOR CV evolutions (a), MOR mass activity evolutions (b), HER LSV evolutions (c), and HER mass activity evolutions (d) for Pt/C, PtT-2.8 and PtT-2.8-6 nm. The accelerated durability tests show 6% activity loss for PtT-2.8 toward MOR after 20,000 potential cycles and 12% activity loss for PtT-4.7 toward HER after 10,000 potential cycles, both surpassing Pt/C. e, Atomic ratio of Pt:Pd before and after the durability tests for PtT-2.8 and PtT-4.7, showing negligible compositional changes. f, g, TEM images, HAADF-STEM images, and lattice profiles of PtT-2.8 (f) and PtT-4.7 (g) after the durability tests, showing negligible structural changes.

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He, T., Wang, W., Shi, F. et al. Mastering the surface strain of platinum catalysts for efficient electrocatalysis. Nature 598, 76–81 (2021).

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