Morphology and Phase Controlled Construction of Pt–Ni Nanostructures for Efficient Electrocatalysis

Abstract

Highly open metallic nanoframes represent an emerging class of new nanostructures for advanced catalytic applications due to their fancy outline and largely increased accessible surface area. However, to date, the creation of bimetallic nanoframes with tunable structure remains a challenge. Herein, we develop a simple yet efficient chemical method that allows the preparation of highly composition segregated Pt-Ni nanocrystals with controllable shape and high yield. The selective use of dodecyltrimethylammonium chloride (DTAC) and control of oleylamine (OM)/oleic acid (OA) ratio are critical to the controllable creation of highly composition segregated Pt-Ni nanocrystals. While DTAC mediates the compositional anisotropic growth, the OM/OA ratio controls the shapes of the obtained highly composition segregated Pt-Ni nanocrystals. To the best of our knowledge, this is the first report on composition segregated tetrahexahedral Pt-Ni NCs. Importantly, by simply treating the highly composition segregated Pt-Ni nanocrystals with acetic acid overnight, those solid Pt-Ni nanocrystals can be readily transformed into highly open Pt-Ni nanoframes with hardly changed shape and size. The resulting highly open Pt-Ni nanoframes are high-performance electrocatalysts for both oxygen reduction reaction and alcohol oxidations, which are far better than those of commercial Pt/C catalyst. Our results reported herein suggest that enhanced catalysts can be developed by engineering the structure/composition of the nanocrystals.

Platinum-nickel alloy excavated nano-multipods with hexagonal close-packed structure and superior activity towards hydrogen evolution reaction

“…One approach is to control the surface structure and increase atom utilization efficiency of noble metal NCs in an effort to optimize their catalytic performance while minimizing the usage of noble metal222324252627. The excavated polyhedral NCs, constructed by orderly assembling of ultrathin nanosheets, combine the advantages of both well-defined surfaces and large surface areas, and thus are promising candidates for efficient and low-cost catalysts2829303132.…”

Platinum–Copper Rhombic Dodecahedral Nanoframes with Tunable Channels as Efficient Bifunctional Electrocatalysts for Fuel‐Cell Reactions

“…In recent years, three‐dimensional (3 D) nanoframes (NFs) have been highlighted, because they have many clear advantages, including the fact that they comprise interconnected edges on the nanoscale, offer 3 D accessible surfaces, have a high surface‐to‐volume ratio, and have high atomic utilization . Metallic NFs have emerged as one of the most intriguing catalysts for PEMFCs and have stimulated researchers to develop synthesis methods to obtain Pt‐based NFs with diverse compositions and morphologies . In this regard, highly open 3 D Pt‐based NFs with large accessible surface areas and interconnected edges would be extremely beneficial for the development of high‐performance Pt‐based catalysts towards the oxygen reduction reaction (ORR) and the electrooxidation of small organic molecules .…”

“…[17][18][19][20] Metallic NFs have emerged as one of the most intriguing catalysts for PEMFCsa nd have stimulated researchers to develop synthesis methods to obtain Pt-based NFs with diversec ompositions and morphologies. [21][22][23][24][25] In this regard, highly open 3D Pt-based NFs with large accessible surface areas and interconnected edges would be extremelyb eneficial for the development of high-performance Pt-based catalysts towards the oxygen reduction reaction (ORR) and the electrooxidationo fs mall organic molecules. [26][27][28][29][30] Althoughe stablished Pt-based NFs have been well studied and many experiments as wella st heoretical calculations have shown that NFs can improve the utilization and performance of Pt-based catalysts, precise control of Pt-based NFs with tunable channels has only been scarcely realized but is, nonetheless, critical for any further enhancementi nt he their performance.Herein, we developed an effectives trategy to prepare an ew type of highly composition-segregatedP t-Cu rhombic dodecahedral nanocrystals (RDH NCs).…”

Noble Metal-Based Nanocomposites for Fuel Cells

“…Dendrite and branch structures not only exhibit large surface area and high active sites, but also significantly relieve the aggregation happened in electrocatalytic stability test [9,33,34]. Highly open noble metal nanocages and nanoframes exhibit enhanced electrocatalytic properties due to their three-dimensional accessible surface atoms [20,35,36]. A nanosegregated noble metal skin on these open structures can further improve the catalytic performance [18,37].…”