Metal‐Free Carbon‐Based Covalent Organic Frameworks with Heteroatom‐Free Units Boost Efficient Oxygen Reduction

Advanced Materials, Год журнала: 2022, Номер 35(7)

Опубликована: Ноя. 25, 2022

Accurate identification of carbon-based metal-free electrocatalyst (CMFE) activity and enhancing their catalytic efficiency for O2 conversion is an urgent challenging task. This study reports a promising strategy to simultaneously develop series covalent organic frameworks (COFs) with well-defined heterocyclic-free biphenyl or fluorenyl units. Unlike heteroatom doping, the developed method not only supplies methyl-induced molecular configuration promote activity, but also provides direct opportunity identify heteroatom-free carbon active centers. The introduction methyl groups (MGs) reversible valence bonds into pristine biphenyl-based COF results in excellent performance half-wave potential 0.74 V versus hydrogen electrode (RHE), which among highest values CMFE-COFs as oxygen reduction reaction (ORR) electrocatalysts. Combined situ Raman spectra theoretical calculations, MG-bound skeleton (DAF-COF) found produce ortho activation, confirming (site-5) adjacent MGs may be attributed opening binding MGs, effectively regulate charge redistribution, well improve transfer reduce energy barrier. insight design highly efficient electrocatalysts via regulation bonds.

Язык: Английский

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Corrosion Chemistry of Electrocatalysts

Advanced Materials, Год журнала: 2022, Номер 34(52)

Опубликована: Март 25, 2022

Abstract Electrocatalysts are the core components of many sustainable energy conversion technologies that considered most potential solution to worldwide and environmental crises. The reliability structure composition pledges electrocatalysts can achieve predictable stable performance. However, during electrochemical reaction, influenced directly by applied potential, electrolyte, adsorption/desorption reactive species, triggering structural compositional corrosion, which affects catalytic behaviors (performance degradation or enhancement) invalidates established structure–activity relationship. Therefore, it is necessary elucidate corrosion behavior mechanism formulate targeted corrosion‐resistant strategies use reconstruction synthesis techniques guide preparation efficient electrocatalysts. Herein, recent developments in electrocatalyst chemistry outlined, including mechanisms, mitigation strategies, syntheses/reconstructions based on typical materials important electrocatalytic reactions. Finally, opportunities challenges also proposed foresee possible development this field. It believed contribution will raise more awareness regarding nanomaterial beyond.

Язык: Английский

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Understanding Synthesis–Structure–Performance Correlations of Nanoarchitectured Activated Carbons for Electrochemical Applications and Carbon Capture

Advanced Functional Materials, Год журнала: 2022, Номер 32(40)

Опубликована: Авг. 7, 2022

Abstract Activated carbons are one of the most important classes high‐surface‐area porous materials. Owing to their unique structure, low price, and large‐scale production technology, these have been traditionally used as sorbents for eliminating contamination. In past decade, many innovations seen in synthesis, applications, theoretical experimental methods. Herein, a comprehensive review up‐to‐date progress activated is presented from viewpoint synthetic chemistry materials science. First, critical textural properties discussed, with special emphasis on texture, heteroatom doping, surface functional groups, partial graphitization. Next, advanced strategies summarized. Special attention given reaction mechanism between activating agents carbon sources, well design controlled forms morphology. Then, applicability various emerging fields covered, including supercapacitors, capacitive deionization, batteries, electrocatalysis, capture. particular, this highlights potential synthesis–structure–property correlations Finally, we present future challenges outlook success energy environmental

Язык: Английский

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Carbon Materials as a Conductive Skeleton for Supercapacitor Electrode Applications: A Review

Nanomaterials, Год журнала: 2023, Номер 13(6), С. 1049 - 1049

Опубликована: Март 14, 2023

Supercapacitors have become a popular form of energy-storage device in the current energy and environmental landscape, their performance is heavily reliant on electrode materials used. Carbon-based electrodes are highly desirable due to low cost abundance various forms, as well ability easily alter conductivity surface area. Many studies been conducted enhance carbon-based supercapacitors by utilizing carbon compounds, including pure nanotubes multistage nanostructures electrodes. These examined characteristics potential applications numerous scrutinized use wide variety nanomaterials, such AC, CNTs, GR, CNCs, others, improve capacitance. Ultimately, this study provides roadmap for producing high-quality using

Язык: Английский

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Ultra-stable sodium ion storage of biomass porous carbon derived from sugarcane

Chemical Engineering Journal, Год журнала: 2022, Номер 445, С. 136344 - 136344

Опубликована: Апрель 14, 2022

Язык: Английский

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