Metal–Organic Framework-Based Catalysts with Single Metal Sites

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 12089 - 12174

Published: May 1, 2020

Metal-organic frameworks (MOFs) are a class of distinctive porous crystalline materials constructed by metal ions/clusters and organic linkers. Owing to their structural diversity, functional adjustability, high surface area, different types MOF-based single sites well exploited, including coordinately unsaturated from nodes metallolinkers, as active species immobilized MOFs. Furthermore, controllable thermal transformation MOFs can upgrade them nanomaterials functionalized with single-atom catalysts (SACs). These unique features derivatives enable serve highly versatile platform for catalysis, which has actually been becoming rapidly developing interdisciplinary research area. In this review, we overview the recent developments catalysis at in emphasis on structures applications thermocatalysis, electrocatalysis, photocatalysis. We also compare results summarize major insights gained works providing challenges prospects emerging field.

Language: Английский

---

Electrocatalysis for CO₂conversion: from fundamentals to value-added products

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(8), P. 4993 - 5061

Published: Jan. 1, 2021

This timely and comprehensive review mainly summarizes advances in heterogeneous electroreduction of CO₂: from fundamentals to value-added products.

Language: Английский

---

Tackling the Activity and Selectivity Challenges of Electrocatalysts toward the Nitrogen Reduction Reaction via Atomically Dispersed Biatom Catalysts

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(12), P. 5709 - 5721

Published: Feb. 18, 2020

Developing efficient catalysts for nitrogen fixation is becoming increasingly important but still challenging due to the lack of robust design criteria tackling activity and selectivity problems, especially electrochemical reduction reaction (NRR). Herein, by means large-scale density functional theory (DFT) computations, we reported a descriptor-based principle explore large composition space two-dimensional (2D) biatom (BACs), namely, metal dimers supported on 2D expanded phthalocyanine (M2-Pc or MM'-Pc), toward NRR at acid conditions. We sampled both homonuclear (M2-Pc) heteronuclear (MM'-Pc) BACs constructed map using N2H* adsorption energy as descriptor, which reduces number promising catalyst candidates from over 900 less than 100. This strategy allowed us readily identify 3 28 BACs, could break metal-based benchmark NRR. Particularly, free difference H* screened out five systems, including Ti2-Pc, V2-Pc, TiV-Pc, VCr-Pc, VTa-Pc, exhibit strong capability suppressing competitive hydrogen evolution (HER) with favorable limiting potential -0.75, -0.39, -0.74, -0.85, -0.47 V, respectively. work not only broadens possibility discovering more N2 also provides feasible rational electrocatalysts helps pave way fast screening other reactions.

Language: Английский

---

Atomic site electrocatalysts for water splitting, oxygen reduction and selective oxidation

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(7), P. 2215 - 2264

Published: Jan. 1, 2020

This review summarized the fabrication routes and characterization methods of atomic site electrocatalysts (ASCs) followed by their applications for water splitting, oxygen reduction selective oxidation.

Language: Английский

---

Advances and Challenges for the Electrochemical Reduction of CO₂ to CO: From Fundamentals to Industrialization

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(38), P. 20627 - 20648

Published: April 17, 2021

Abstract The electrochemical carbon dioxide reduction reaction (CO 2 RR) provides an attractive approach to convert renewable electricity into fuels and feedstocks in the form of chemical bonds. Among different CO RR pathways, conversion is considered one most promising candidate reactions because its high technological economic feasibility. Integrating catalyst electrolyte design with understanding catalytic mechanism will yield scientific insights promote this technology towards industrial implementation. Herein, we give overview recent advances challenges for selective CO. Multidimensional engineering are also summarized. Furthermore, studies on large‐scale production highlighted facilitate industrialization . To conclude, remaining future directions application generate highlighted.

Language: Английский

---

Atomically Dispersed Binary Co‐Ni Sites in Nitrogen‐Doped Hollow Carbon Nanocubes for Reversible Oxygen Reduction and Evolution

Advanced Materials, Journal Year: 2019, Volume and Issue: 31(49)

Published: Oct. 16, 2019

With the inspiration of developing bifunctional electrode materials for reversible oxygen electrocatalysis, one strategy heteroatom doping is proposed to fabricate dual metal single-atom catalysts. However, identification and mechanism functions polynary structures remain elusive. Atomically dispersed binary Co-Ni sites embedded in N-doped hollow carbon nanocubes (denoted as CoNi-SAs/NC) are synthesized via pyrolysis dopamine-coated metal-organic frameworks. The atomically isolated bimetallic configuration CoNi-SAs/NC identified by combining microscopic spectroscopic techniques. When employing electrocatalysts alkaline medium, resultant hybrid manifests outstanding catalytic performance reduction/evolution reactions, boosting realistic rechargeable zinc-air batteries with high efficiency, low overpotential, robust reversibility, superior other counterparts state-of-the-art precious-metal Theoretical computations based on density functional theory demonstrate that homogenously single atoms synergistic effect neighboring center can optimize adsorption/desorption features decrease overall reaction barriers, eventually promoting electrocatalysis. This work not only sheds light controlled synthesis advanced materials, but also provides deeper understanding structure-performance relationships nanocatalysts multiple active various applications.

Language: Английский

---

Bismuth Single Atoms Resulting from Transformation of Metal–Organic Frameworks and Their Use as Electrocatalysts for CO₂ Reduction

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(42), P. 16569 - 16573

Published: Oct. 5, 2019

The electrocatalytic reduction reaction of CO2 (CO2RR) is a promising strategy to promote the global carbon balance and combat climate change. Herein, exclusive Bi-N4 sites on porous networks can be achieved through thermal decomposition bismuth-based metal-organic framework (Bi-MOF) dicyandiamide (DCD) for CO2RR. Interestingly, in situ environmental transmission electron microscopy (ETEM) analysis not only directly shows from Bi-MOF into Bi nanoparticles (NPs) but also exhibits subsequent atomization NPs assisted by NH3 released DCD. Our catalyst high intrinsic activity CO conversion, with Faradaic efficiency (FECO up 97%) turnover frequency 5535 h-1 at low overpotential 0.39 V versus reversible hydrogen electrode. Further experiments density functional theory results demonstrate that single-atom site dominating active center simultaneously activation rapid formation key intermediate COOH* free energy barrier.

Language: Английский

---

In Situ/Operando Electrocatalyst Characterization by X-ray Absorption Spectroscopy

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(2), P. 882 - 961

Published: Sept. 28, 2020

During the last decades, X-ray absorption spectroscopy (XAS) has become an indispensable method for probing structure and composition of heterogeneous catalysts, revealing nature active sites establishing links between structural motifs in a catalyst, local electronic structure, catalytic properties. Here we discuss fundamental principles XAS describe progress instrumentation data analysis approaches undertaken deciphering near edge (XANES) extended fine (EXAFS) spectra. Recent usages field catalysis, with emphasis on examples concerning electrocatalysis, will be presented. The latter is rapidly developing immense industrial applications but also unique challenges terms experimental characterization restrictions advanced modeling required. This review highlight new insight that can gained complex real-world electrocatalysts including their working mechanisms dynamic processes taking place course chemical reaction. More specifically, situ operando to probe catalyst’s interactions environment (support, electrolyte, ligands, adsorbates, reaction products, intermediates) its structural, chemical, transformations as it adapts conditions.

Language: Английский

---

Heterogeneous Single‐Atom Catalysts for Electrochemical CO₂ Reduction Reaction

Advanced Materials, Journal Year: 2020, Volume and Issue: 32(34)

Published: July 9, 2020

The electrochemical CO2 reduction reaction (CO2 RR) is of great importance to tackle the rising concentration in atmosphere. RR can be driven by renewable energy sources, producing precious chemicals and fuels, with implementation this process largely relying on development low-cost efficient electrocatalysts. Recently, a range heterogeneous potentially single-atom catalysts (SACs) containing non-precious metals coordinated earth-abundant elements have emerged as promising candidates for RR. Unfortunately, real catalytically active centers key factors that govern catalytic performance these SACs remain ambiguous. Here, ambiguity addressed developing fundamental understanding RR-to-CO SACs, CO accounts major product from SACs. mechanism, rate-determining steps, control activity selectivity are analyzed both experimental theoretical studies. Then, synthesis, characterization, discussed. Finally, challenges future pathways highlighted hope guiding design promote understand

Language: Английский

---

Non-Bonding Interaction of Neighboring Fe and Ni Single-Atom Pairs on MOF-Derived N-Doped Carbon for Enhanced CO₂ Electroreduction

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(46), P. 19417 - 19424

Published: Nov. 15, 2021

Single-atom catalysts (SACs), featuring high atom utilization, have captured widespread interests in diverse applications. However, the single-atom sites SACs are generally recognized as independent units and interplay of adjacent is largely overlooked. Herein, by direct pyrolysis MOFs assembled with Fe Ni-doped ZnO nanoparticles, a novel Fe1-Ni1-N-C catalyst, neighboring Ni pairs decorated on nitrogen-doped carbon support, has been precisely constructed. Thanks to synergism pairs, presents significantly boosted performances for electrocatalytic reduction CO2, far surpassing Fe1-N-C Ni1-N-C separate or single atoms. Additionally, also exhibits superior performance excellent CO selectivity durability Zn-CO2 battery. Theoretical simulations reveal that, Fe1-Ni1-N-C, atoms can be highly activated via non-bonding interaction, facilitating formation COOH* intermediate thereby accelerating overall CO2 reduction. This work supplies general strategy construct containing multiple metal species reveals vital importance communitive effect between toward improved catalysis.

Language: Английский

---