Anchoring zero valence single atoms of nickel and iron on graphdiyne for hydrogen evolution

Direct Synthesis of Crystalline Graphdiyne Analogue Based on Supramolecular Interactions

The synthesis of graphdiyne with an ordered internal structure is highly attractive for its various scientific and application investigations. We reported herein a rational method to fabricate a graphdiyne analogue with the help of supramolecular chemistry. The introduction of π-π/CH-π interactions controlled the conformations of the precursors and afforded multilayer graphdiyne analogue Ben-GDY through the wet chemical method. The in-plane periodicity of the multilayer Ben-GDY was corroborated by transmission electron microscopy and selected area electron diffraction, which showed a pattern well matched with ABC-style stacking.

Overall water splitting by graphdiyne-exfoliated and -sandwiched layered double-hydroxide nanosheet arrays

It is of great urgency to develop efficient, cost-effective, stable and industrially applicable electrocatalysts for renewable energy systems. But there are still few candidate materials. Here we show a bifunctional electrocatalyst, comprising graphdiyne-exfoliated and -sandwiched iron/cobalt layered double-hydroxide nanosheet arrays grown on nickel foam, for the oxygen and hydrogen evolution reactions. Theoretical and experimental data revealed that the charge transport kinetics of the structure were superior to iron/cobalt layered double-hydroxide, a prerequisite for improved electrocatalytic performance. The incorporation with graphdiyne increased the number of catalytically active sites and prevented corrosion, leading to greatly enhanced electrocatalytic activity and stability for oxygen evolution reaction, hydrogen evolution reaction, as well as overall water splitting. Our results suggest that the use of graphdiyne might open up new pathways for the design and fabrication of earth-abundant, efficient, functional, and smart electrode materials with practical applications.

The need for cheap water-splitting materials in order to scale-up and commercialize solar-to-fuel technologies is urgent, but there are still few candidate materials. Here, authors integrate layered double hydroxides with graphdiyne as high-performance overall water-splitting electrocatalysts.

Ultrathin Nanosheet of Graphdiyne-Supported Palladium Atom Catalyst for Efficient Hydrogen Production

Atomic catalysts are promising alternatives to bulk catalysts for the hydrogen evolution reaction (HER), because of their high atomic efficiencies, catalytic activities, and selectivities. Here, we report the ultrathin nanosheet of graphdiyne (GDY)-supported zero-valent palladium atoms and its direct application as a three-dimensional flexible hydrogen-evolving cathode. Our theoretical and experimental findings verified the successful anchoring of Pd⁰ to GDY and the excellent catalytic performance of Pd⁰/GDY. At a very low mass loading (0.2%: 1/100 of the 20 wt % Pt/C), Pd⁰/GDY required only 55 mV to reach 10 mA cm⁻² (smaller than 20 wt % Pt/C); it showed larger mass activity (61.5 A mg_metal⁻¹) and turnover frequency (16.7 s⁻¹) than 20 wt % Pt/C and long-term stability during 72 hr of continuous electrolysis. The unusual electrocatalytic properties of Pd⁰/GDY originate from its unique and precise structure and valence state, resulting in reliable performance as an HER catalyst.

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A general approach for synthesis of zero-valent palladium atoms on graphdiyne

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Pd atoms anchored at the angle site of the alkyne ring in GDY

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The obtained atomic catalyst shows better catalytic activity than commercial Pt/C

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The unique structure maintains and guarantees efficient HER process

Graphdiyne: Recent Achievements in Photo- and Electrochemical Conversion

As a rising star of carbon allotropes, graphynes (GYs) merely consist of sp- and sp2-hybridized carbon atoms, which endow them a large conjugated network and expanded 2D porous structure. With unique topological structure, GYs display unusual semiconducting properties, especially in the aspects of charge mobility and electron transport. Among the members of the GY family, only graphdiyne (GD) can be successfully synthesized in large quantities. The advanced properties of GD make it promising in various applications. Here, the recent progress in the synthesis of GD and GD-based composites is reviewed as well as their applications in photorelated and electrocatalytic applications. It is hoped that this Review will promote the development and applications of carbon chemistry.

A cocoon silk chemistry strategy to ultrathin N-doped carbon nanosheet with metal single-site catalysts

Development of single-site catalysts supported by ultrathin two-dimensional (2D) porous matrix with ultrahigh surface area is highly desired but also challenging. Here we report a cocoon silk chemistry strategy to synthesize isolated metal single-site catalysts embedded in ultrathin 2D porous N-doped carbon nanosheets (M-ISA/CNS, M = Fe, Co, Ni). X-ray absorption fine structure analysis and spherical aberration correction electron microscopy demonstrate an atomic dispersion of metal atoms on N-doped carbon matrix. In particular, the Co-ISA/CNS exhibit ultrahigh specific surface area (2105 m² g⁻¹) and high activity for C–H bond activation in the direct catalytic oxidation of benzene to phenol with hydrogen peroxide at room temperature, while the Co species in the form of phthalocyanine and metal nanoparticle show a negligible activity. Density functional theory calculations discover that the generated O = Co = O center intermediates on the single Co sites are responsible for the high activity of benzene oxidation to phenol.

Single-site catalysts supported by ultrathin two-dimensional (2D) porous matrix are desirable for catalytic reactions, yet their synthesis remains a great challenge. Herein the authors report a cocoon silk chemistry strategy to synthesize isolated metal single-site catalysts embedded in ultrathin 2D porous N-doped carbon nanosheets.

C2N: an excellent catalyst for the hydrogen evolution reaction

Based on first-principles calculations, we study the hydrogen evolution reaction (HER) on metal-free C₂N and make efforts to improve its catalytic performance.