Pt-Based electrocatalysts with high atom utilization efficiency: from nanostructures to single atoms

Previous works have found that the surface atomic structure and composition of catalysts play critical roles in the electrocatalytic performance of Pt-based catalysts. [5][6][7] Accordingly, nanoalloys with various atomic arrangement style including controlled composition or shape, core-shell structure, heterostructure, hollow structure and ordered structure have been designed and proved to be effective ways to modify the catalytic performance of Pt-based catalyst. [8][9][10][11][12] Furthermore, well-designed alloyed particles with Pt-enriched surfaces should possess a suitable electronic structure for ORR and thus meet both high performance and lower cost. [13] Low-coordination metal atoms often function as the catalytically active sites, while the specific activity per metal atom usually increases with decreasing size of the metal particles. [14,15] Additionally, smaller size also indicates higher dispersion of Pt atoms and higher utilization efficiency. [16] However, the surface free energy of metals increases significantly with decreasing particle size, promoting aggregation of small clusters. [17] Monodispersed superfine alloyed clusters have many advantages, such as high Pt-utilization efficiency and synergistic effects arising from neighboring metal atoms. [18] More importantly, by forming ordered intermetallic PtM nanocrystals with some metal M, the higher mixing enthalpy and stronger atomic interactions between Pt and M atoms would make PtM highly stable under electrochemical tests in both acidic and alkaline solutions. [19][20][21][22] However, in general, forming Industrial applications of Pt-based oxygen-reduction-reaction (ORR) catalysts are limited by high cost and low stability. Here, facile large-scale synthesis of sub-3-nm ordered Pt 3 In clusters on commercial carbon black as ORR catalyst that alleviates both these shortcomings is reported. As-prepared Pt 3 In/C exhibits a mass activity of 0.71 mA mg −1 and a specific area activity of 0.91 mA cm −2 at 0.9 V vs reversible hydrogen electrode, which are 4.1 and 2.7 times the corresponding values of commercial Pt/C catalysts. The asprepared ordered Pt 3 In/C catalyst is also remarkably stable with negligible activity and structural decay after 20 000 accelerated electrochemical durability cycles, due to its ordered structure. Density-functional-theory calculations demonstrate that ordered-Pt 3 In is more energetically favorable for ORR than the commercial Pt/C catalysts because ∆G O is closer to the peak of the volcano plot after ordered incorporation of indium atoms.

show abstract

“…

…”

mentioning

confidence: 99%

Sub‐3 nm Intermetallic Ordered Pt₃In Clusters for Oxygen Reduction Reaction

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Importantly, the photochemical transformation of sunlight into chemical energy has occurred naturally in green plants for millions of years, and is known as photosynthesis. However, sluggish reaction kinetics and the subsequent use of precious‐metal‐based catalysts to catalyze electrochemical and photochemical reactions are found to be major limitations to employing these processes on a large scale . Several materials such as metal oxides, phosphides, sulfides, chalcogenides, inorganic or organic–inorganic hybrid porous and carbon‐based materials are known in the literature separately as either electrocatalysts or photocatalysts, but purely organic‐based catalysts working as electro‐ or photocatalysts have hardly been explored …”

Section: Introductionmentioning

confidence: 99%

“…However,s luggish reactionk inetics and the subsequent use of precious-metal-based catalystst oc atalyze electrochemical and photochemical reactions are found to be majorl imitations to employing these processes on al arge scale. [16][17][18][19] Severalm aterials such as metal oxides, phosphides, sulfides, chalcogenides, inorganic or organic-inorganic hybrid porousa nd carbon-based materials are knowni nt he literature separately as either electrocatalysts [4,[20][21][22][23][24][25][26][27][28] or photocatalysts, [14,[29][30][31][32] but purely organic-based catalysts working as electro-or photocatalystshave hardly been explored. [33][34][35][36][37][38] Conjugated microporous polymers( CMPs) are an emerging class of porous organic materials, which have demonstrated a treasuret rove of applications.…”

Section: Introductionmentioning

confidence: 99%

Bimodal Heterogeneous Functionality in Redox‐Active Conjugated Microporous Polymer toward Electrocatalytic Oxygen Reduction and Photocatalytic Hydrogen Evolution

Singh

Verma

Samanta

et al. 2020

Chemistry A European J

View full text Add to dashboard Cite

The designing and development of heterogeneous catalysts for conversion of renewable energy to chemical energies by electrochemical as well as photochemical processes is at the forefront of energy research. In this work, two new donor–acceptor‐based redox‐active conjugated microporous polymers (CMPs) (TAPA‐OPE‐mix and TAPA‐OPE‐gly) are synthesized through Schiff base condensation reaction using a microwave synthesizer. Notably, the asymmetric and symmetric bola‐amphiphilic nature of the OPE struts results in distinct nanostructuring and morphologies in the CMPs. Interestingly, both CMPs show impressive heterogeneous catalytic activity toward electrochemical O2 reduction and photocatalytic H2 evolution reactions, and therefore, act as bimodal electro‐ and photocatalytic porous organic materials. Furthermore, the redox‐active property of the CMPs is exploited for in situ generation and stabilization of platinum nanoparticles (Pt), and these Pt@CMPs exhibit significantly enhanced photocatalytic activity.

show abstract

“…Up to now, various catalysts such as noble or transition metal particles, metal phosphates/sulfides/oxides, and nonmetallic materials have been developed . Among these catalysts, noble metal (i.e., Pt, Ru, and Pd) nanoparticles show superior catalytic property due to their unfilled d orbitals and moderate Gibbs free energy of intermediates in electrocatalytic process . However, in view of the cost, transition metals (Fe, Co, and Ni)‐based catalysts with the similar unfilled d orbital that also display the good catalytic properties are promising.…”

Section: Introductionmentioning

confidence: 99%

Single Atoms on Graphene for Energy Storage and Conversion

et al. 2019

View full text Add to dashboard Cite

Single atoms are attracting much attention in the field of energy conversion and storage due to their maximal atomic utilization, high efficiency, and good selectivity. Moreover, their unique electronic structure could improve the intrinsic activity of the active sites. However, the high surface free energy of single atoms inevitably results in their serious aggregation, leading to degraded catalytic activity and poor cycling life. To solve these issues, supports with high surface areas have to be developed to reduce loading density of single atoms and further decrease the surface free energy. Furthermore, engineering the active sites of these substrates can also regulate chemical coordination of single atoms, enhancing their catalytic performance. Owing to high surface area, excellent conductivity and adjustable surface properties, graphene is widely utilized to load atomic metal catalysts. In this review, the fabrication strategies and characterization methods of single atoms on graphene (SAG) are summarized first. Subsequently, the electrochemical applications of SAG on the oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, carbon dioxide reduction, and methane oxidation are discussed in detail. Finally, the future developments and prospects in fabrication and application of SAG are also discussed.

show abstract

Pt-Based electrocatalysts with high atom utilization efficiency: from nanostructures to single atoms

Abstract: This review presents recent developments in the design and synthesis of Pt-based catalysts with high atom utilization efficiency and their enhanced catalytic performance in electrochemical catalytic reactions.

Cited by 431 publications

References 157 publications

Sub‐3 nm Intermetallic Ordered Pt₃In Clusters for Oxygen Reduction Reaction

Sub‐3 nm Intermetallic Ordered Pt₃In Clusters for Oxygen Reduction Reaction

Bimodal Heterogeneous Functionality in Redox‐Active Conjugated Microporous Polymer toward Electrocatalytic Oxygen Reduction and Photocatalytic Hydrogen Evolution

Single Atoms on Graphene for Energy Storage and Conversion

Contact Info

Product

Resources

About

Pt-Based electrocatalysts with high atom utilization efficiency: from nanostructures to single atoms

Abstract: This review presents recent developments in the design and synthesis of Pt-based catalysts with high atom utilization efficiency and their enhanced catalytic performance in electrochemical catalytic reactions.

Cited by 431 publications

References 157 publications

Sub‐3 nm Intermetallic Ordered Pt3In Clusters for Oxygen Reduction Reaction

Sub‐3 nm Intermetallic Ordered Pt3In Clusters for Oxygen Reduction Reaction

Bimodal Heterogeneous Functionality in Redox‐Active Conjugated Microporous Polymer toward Electrocatalytic Oxygen Reduction and Photocatalytic Hydrogen Evolution

Single Atoms on Graphene for Energy Storage and Conversion

Contact Info

Product

Resources

About

Sub‐3 nm Intermetallic Ordered Pt₃In Clusters for Oxygen Reduction Reaction

Sub‐3 nm Intermetallic Ordered Pt₃In Clusters for Oxygen Reduction Reaction