Fine‐Tuning Intrinsic Strain in Penta‐Twinned Pt–Cu–Mn Nanoframes Boosts Oxygen Reduction Catalysis

Abstract

Tuning the intrinsic strain of Pt‐based nanomaterials has shown great promise for improving the oxygen reduction reaction (ORR) performance. Herein, reported is a tunable surface strain in penta‐twinned ternary Pt–Cu–Mn nanoframes (NFs). Pt–Cu–Mn ultrafine NFs (UNFs) exhibit ≈1.5% compressive strain compared to Pt–Cu–Mn pentagonal NFs (PNFs) and show the superior activity toward ORR in an alkaline environment. Specifically, the specific and mass activity of Pt–Cu–Mn UNFs are 3.38 mA cm−2 and 1.45 A mg−1, respectively, which is 1.45 and 1.71 times higher than that of Pt–Cu–Mn PNFs, demonstrating that compressive strain in NFs structure can effectively enhance the catalytic activity of ORR. Impressively, Pt–Cu–Mn UNFs exhibit 8.67 and 9.67 times enhanced specific and mass activity compared with commercial Pt/C. Theoretical calculations reveal that compression on the surface of Pt–Cu–Mn UNFs can weaken the bonding strengths and adsorption of oxygen‐containing intermediates, resulting in an optimal condition for ORR.

Atomic‐Scale Interface Engineering: Boosting Oxygen Electroreduction over Supported Ternary Alloys Fabricated by Carbon‐Assisted Galvanic Replacement

“…In this way, the increase in lattice shrinkage should lead to the increase in strain that can contribute to the enhancement of ORR activity of the supported alloy, as suggested in literature. [ 21,32 ] Second, we can observe that the recorded PDOS diagrams of surface Pt atoms show well the electronic coordination for the three tested samples, as shown in Figure 8c. Based on the data in Figure 8c, the determined d‐band center of each sample is shown in Figure 8d.…”

“…In this way, the increase in lattice shrinkage should lead to the increase in strain that can contribute to the enhancement of ORR activity of the supported alloy, as suggested in literature. [21,32] Second, we can observe that the recorded PDOS diagrams of surface Pt which may result from interface interaction between the alloy and carbon in their hybrids. It is believed that the d-band center is closely related to the adsorption capacity of oxygen-containing groups during the ORR.…”

Boosting Both Electrocatalytic Activity and Durability of Metal Aerogels via Intrinsic Hierarchical Porosity and Continuous Conductive Network Backbone Preservation

“…A high‐resolution TEM (HR‐TEM) image (Figure 3b) shows the existence of plenty of defects and kinks along the interconnected nanowires, which are believed to be beneficial for the electrocatalytic activity. [ 4,33,34 ] The crystalline domains containing lattice planes with interplanar distances of about 0.230 nm are widely distributed on the aerogels. These lattice planes are assigned to the (111) plane of face‐centered cubic (fcc) PtAg alloy.…”

A fundamental comprehension and recent progress in advanced Pt‐based ORR nanocatalysts

“…The surface strain engineering of Pt-based catalysts has obtained researcher's attention due to its immense potential in modulating the electrocatalytic performance. 56,59,60 Strain effect can tune the lattice fringe of surface Pt atoms to improve the electrocatalytic activity while the foreign metals are introduced into the depths of nanocatalysts greater than 1 nm. 16,[61][62][63][64] Herein, we present the fundamental advances in theoretical modelings to further understand the surface strain effect of Pt-based catalyst on ORR.…”