다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Isolated atoms featuring unique reactivity are at the heart of enzymatic and homogeneous catalysts. In contrast, although the concept has long existed, single-atom heterogeneous catalysts (SACs) have only recently gained prominence. Host materials have similar functions to ligands in homogeneous catalysts, determining the stability, local environment, and electronic properties of isolated atoms and thus providing a platform for tailoring heterogeneous catalysts for targeted applications. Within just a decade, we have witnessed many examples of SACs both disrupting diverse fields of heterogeneous catalysis with their distinctive reactivity and substantially enriching our understanding of molecular processes on surfaces. To date, the term SAC mostly refers to late transition metal-based systems, but numerous examples exist in which isolated atoms of other elements play key catalytic roles. This review provides a compositional encyclopedia of SACs, celebrating the 10th anniversary of the introduction of this term. By defining single-atom catalysis in the broadest sense, we explore the full elemental diversity, joining different areas across the whole periodic table, and discussing historical milestones and recent developments. In particular, we examine the coordination structures and associated properties accessed through distinct single-atom-host combinations and relate them to their main applications in thermo-, electro-, and photocatalysis, revealing trends in element-specific evolution, host design, and uses. Finally, we highlight frontiers in the field, including multimetallic SACs, atom proximity control, and possible applications for multistep and cascade reactions, identifying challenges, and propose directions for future development in this flourishing field.

Single-Atom Catalysts across the Periodic Table.

Integrated Conductive Hybrid Architecture of Metal–Organic Framework Nanowire Array on Polypyrrole Membrane for All-Solid-State Flexible Supercapacitors

N-doped honeycomb-like porous carbon towards high-performance supercapacitor

Fullerene-Based In Situ Doping of N and Fe into a 3D Cross-Like Hierarchical Carbon Composite for High-Performance Supercapacitors

Development of high-performance oxygen reduction reaction (ORR) catalysts to replace the noble metal-based materials is critical for energy applications. Fullerenes, in the form of carbon cage with the intrinsic curvature and pentagons, have been theoretically simulated as promising ORR catalysts via atom doping and defect modification. However, fullerene-based catalysts remain challenging in achieving ORR performance comparable to Pt/C given the lack of fullerene host-dopant synergism. A rational strategy is to anchor active species on fullerene cage to enhance ORR response. Herein, a Fe, Ndecorated fullerene derivative (N-methyl-2-ferrocenyl-pyrrolidinofullerene C60) is activated under NH3 stream to achieving porous Fe3O4/N-C nanomaterials with high catalytic activity toward ORR. The optimal NH3-etching temperature of 700 °C gives rise to open-pore structures, large surface area, favorable N doping, active Fe3O4 sites and short-range ordered nanographene. Through these synergetic effects, the fullerene-derived FMN700 exhibits superior ORR activity, along with respectable durability and tolerance to methanol, which surpass most of the reported fullerene-based carbon materials. This work provides a new strategy for the design and synthesis of porous carbon composites as a new class of catalysts for highperformance ORR.

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NH3-activated Fullerene Derivative Hierarchical Microstructures to Porous Fe3O4/N-C for Oxygen Reduction Reaction and Zn-air Battery

Heteroatom-doped carbon nanomaterials are effective metal-free catalysts for organic reactions. However, S-doped carbocatalysts are relatively unexplored due to challenges related to the synthesis of S-doped nanocarbon. Herein, we employed a facile, low-cost and eco-friendly approach to construct a N,S co-doped hierarchical carbon nanomaterial (NSHC) via the pyrolysis of an azo-sulphonate dye pollutant intercalated layered double hydroxide. The as-prepared NSHC possesses a two-dimensional hierarchical porous structure with ultrathin carbon nanosheets uniformly distributed on hexagonal carbon nanoplates, endowing the material with a high specific surface area of 1260 m2 g−1. Attributed to the synergistic effects of N,S co-doping, the high specific surface area and the interconnected porous architecture, NSHC demonstrates excellent catalytic activity and selectivity in the reduction of nitroarenes. Among the reported carbocatalysts for nitrobenzene reduction using hydrazine hydrate, NSHC shows the highest turnover frequency value of 4.89 h−1. Furthermore, NSHC exhibits remarkable recyclability and generality for the reduction of various aromatic nitro compounds.

Eco-friendly synthesis of N,S co-doped hierarchical nanocarbon as a highly efficient metal-free catalyst for the reduction of nitroarenes

Broadband photodetectors fabricated with organic molecules have the advantages of low cost, high flexibility, easy processing and low-temperature requirement. Fullerene molecules, due to their electron accepting and photoinduced electron transfer properties, are potential materials for photodetectors. However, fullerene has a narrow light absorption spectrum range, and realization of large-area fullerene-based broadband photodetectors remains a challenge. Herein, we broaden the absorption wavelength range of fullerene through molecular engineering, i.e. adding a donor molecule, nickel tetraphenylporphyrin (NiTPP) with strong visible light absorption capacity, onto the fullerene cage to form a donor–acceptor dyad (NiTPP-C60). Moreover, large-area nickel porphyrin–fullerene (NiTPP-C60) single-crystal arrays were prepared by applying a liquid-bridge induced assembly method. Combining the excellent visible light absorption properties of porphyrin and the good electron transport characteristic of fullerene, photodetectors fabricated with NiTPP-C60 single-crystal arrays show a fast photoelectric response with τon < 0.09 s at 350 nm, τon < 0.10 s at 425 nm and τon < 0.08 s at 530 nm, and the highest responsivity of 11.9 A W−1 at 425 nm. This study provides a new strategy toward the fabrication of high-performance fullerene broadband photodetectors and presents a versatile method for the design of large-area well-aligned organic single-crystal arrays for practical electronic applications.

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Molecular engineering for high-performance fullerene broadband photodetectors

Fullerene microcrystals have been well prepared by the conventional liquid–liquid interface precipitation (LLIP) method, and the crystal structures can be manipulated by solvent combination. Aromatic and alcoholic solvents are widely used as good and poor solvents, respectively, in LLIP. However, water with higher polarity has been rarely utilized as a poor solvent for the morphology engineering of fullerenes, particularly in the morphology control of fullerene derivatives. Herein, the water-regulated morphology of a fullerene derivative, namely ferrocenylpyrrolidine C60 (denoted as FC), is investigated via the LLIP method. By simply modulating the combination of a good solvent (aromatic isopropylbenzene, IPB) and the poor solvents (alcohols), three-dimensional (3D) hierarchical microspheres of FC are obtained. Surprisingly, when water is introduced as one of poor solvents in the LLIP process, one-dimensional (1D) microneedles are obtained. The presence of water controls the liquid–liquid interface, the external environment and kinetics of the crystal growth, thereby promoting the morphological evolution from 3D hierarchical microspheres to 1D microneedles. Moreover, the solvated 1D microneedles exhibit enhanced photoluminescence (PL) and photocurrent responses in virtue of the highly ordered molecule arrangement and solvent (IPB) embedding in the crystal lattice. The water-regulated morphology engineering of FC provides a new strategy for the growth and morphology control of fullerene microcrystals.

Zhiyao Peng

Papers

Fullerene-Based In Situ Doping of N and Fe into a 3D Cross-Like Hierarchical Carbon Composite for High-Performance Supercapacitors

NH3-activated Fullerene Derivative Hierarchical Microstructures to Porous Fe3O4/N-C for Oxygen Reduction Reaction and Zn-air Battery

Eco-friendly synthesis of N,S co-doped hierarchical nanocarbon as a highly efficient metal-free catalyst for the reduction of nitroarenes

Molecular engineering for high-performance fullerene broadband photodetectors

From 3D hierarchical microspheres to 1D microneedles: the unique role of water in the morphology control of ferrocenylpyrrolidine C60 microcrystals