Vertex‐Reinforced PtCuCo Ternary Nanoframes as Efficient and Stable Electrocatalysts for the Oxygen Reduction Reaction and the Methanol Oxidation Reaction

Abstract

Noble metal binary alloy nanoframes have emerged as a new class of fuel cell electrocatalysts because of their intrinsic high catalytic surface area and accompanied high catalytic activity. However, their inferior structural and compositional stability during catalysis pose as formidable huddles to their practical applications. Herein, it is reported that introduction of an additional component to the binary catalytic system may serve as a simple and effective means of enhancing the structural and compositional stability of nanoframe‐based electrocatalysts. It is demonstrated that in situ doping of Co to the PtCu alloy nanoframe yields a ternary PtCuCo rhombic dodecahedral nanoframe (Co‐PtCu RNF) with a reinforced vertex structure. Co‐PtCu RNF exhibits superior electrocatalytic activity and durability for the oxygen reduction reaction to those of PtCu rhombic dodecahedral nanoframe (PtCu RNF) and Pt/C catalysts, due to its ternary composition and vertex‐strengthened frame structure. Furthermore, Co‐PtCu RNF shows enhanced activity for the methanol oxidation reaction as compared to PtCu RNF and Pt/C.

Atomic layer deposited Pt/Cu bimetallic catalysts for use in high‐performance fuel cell cathodes

“…As shown in Figure 2B, HRTEM confirms that the respective lattice spacings of the Pt (111) and (200) planes are 0.227 and 0.19 nm, which exactly match our reference values from previous studies 14,15 . Figure 2C confirms that the lattice spacing of the Cu (002) plane is 0.181 nm, again matching the reference value 16 . The uniformly distributed shapes of the Pt and Cu catalysts in the STEM EDS results (Figures 2E,F) may be attributed to the uniform formation of the composite catalyst layer due to the penetration of Pt nanoparticles during Pt catalyst deposition via PEALD.…”

Polyhedron-Assembled Ternary PtCuCo Nanochains: Integrated Functions Enhance the Electrocatalytic Performance of Methanol Oxidation at Elevated Temperature

“…These results indicated that Pt alloying with Cu and/or Co can improve the MOR activity. Figure c shows that the MOR activity and surface strain of the prepared nanochains exhibited a volcano relationship, and the Pt 45 Cu 35 Co 20 nanochains displayed the best activity due to their strain (2.76%) near the peak of the volcano map, which was consistent with the previous reports. , The compressive strain would weaken the adsorption strength of the reactant and intermediates and facilitate the electrocatalytic performance. ,,, The SA/MA of Pt 45 Cu 35 Co 20 nanochains was 9.25/10.47 times that of commercial Pt black (Figure d). Figure S5 indicates that the reaction kinetics on Pt 45 Cu 35 Co 20 nanochains was much faster than on commercial Pt black at elevated temperature.…”

Segmentation and Re-encapsulation of Porous PtCu Nanoparticles by Generated Carbon Shell for Enhanced Ethylene Glycol Oxidation and Oxygen-Reduction Reaction

“…The XRD patterns of the PtCu@SiO 2 @C intermediate products (Figure A-c,d) retained the diffraction peaks of the PtCu alloy before and after calcination, and the 2θ value of these peaks between the two remain unchanged. This result indicated that the alloy-phase composition remained intact . As shown in Figure A-e, the XRD pattern of UsPtCu@C exhibited a similar fcc structure, in agreement with the TEM observation.…”

“…This result indicated that the alloyphase composition remained intact. 10 As shown in Figure 4A-e, the XRD pattern of UsPtCu@C exhibited a similar fcc structure, in agreement with the TEM observation. A broad peak at ∼2θ = 25°was indexed to the (002) reflection of the carbon phase, which indicated the formation of amorphous or disordered carbon in the final product.…”

“…The high-resolution TEM image of UsPtCu@C (Figure 3a) shows lattice fringes with interfringe distances of ∼0.219, 0.188, and 0.136 nm, which can be indexed to the (111), (200), and (220) planes of the Pt-based face-centered cubic (fcc) phase, respectively. 10 The same lattice fringe in Pt/Cu and Pt/Cu@ SiO 2 (Figure 2b,d) confirmed that the UsPtCu@C nanostructures had been fabricated and existed in the polycrystalline state. Abundant fuzzy steps and platform atoms are visible in Figure 3a, such as the white virtual frames, which proved the successful coating and filling of amorphous carbon.…”