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Fullerene has a definite 0D closed‐cage molecular structure composed of merely sp2‐hybridized carbon atoms, enabling it to serve as an important building block that is useful for constructing supramolecular assemblies and micro/nanofunctional materials. Conversely, graphene has a 2D layered structure, possessing an exceptionally large specific surface area and high carrier mobility. Likewise, other emerging graphene‐analogous 2D nanomaterials, such as graphitic carbon nitride (g‐C3N4), transition‐metal dichalcogenides (TMDs), hexagonal boron nitride (h‐BN), and black phosphorus (BP), show unique electronic, physical, and chemical properties, which, however, exist only in the form of a monolayer and are typically anisotropic, limiting their applications. Upon hybridization with fullerenes, noncovalently or covalently, the physical/chemical properties of 2D nanomaterials can be tailored and, in most cases, improved, significantly extending their functionalities and applications. Here, an exhaustive review of all types of hybrids of fullerenes and 2D nanomaterials, such as graphene, g‐C3N4, TMDs, h‐BN, and BP, including their preparations, structures, properties, and applications, is presented. Finally, the prospects of fullerene‐2D nanomaterial hybrids, especially the opportunity of creating unknown functional materials by means of hybridization, are envisioned. An exhaustive review of the hybrids of fullerenes with 2D materials including graphene, graphitic carbon nitride, transition‐metal dichalcogenides, hexagonal boron nitride, and black phosphorus is presented, focused on their preparations, structures, properties, and applications. Upon hybridization with fullerenes noncovalently or covalently, physical/chemical properties of 2D materials can be tailored and in most cases improved, significantly extending their functionalities and applications.

Few-layer black phosphorus (BP) with an anisotropic two-dimensional (2D)-layered structure shows potential applications in photoelectric conversion and photocatalysis, but is easily oxidized under ambient condition preferentially at its edge sites. Improving the ambient stability of BP nanosheets has been fulfilled by chemical functionalization, however this functionalization is typically non-selective. Here we show that edge-selective functionalization of BP nanosheets by covalently bonding stable C 60 molecules leads to its significant stability improvement. Owing to the high stability of the hydrophobic C 60 molecule, C 60 functions as a sacrificial shield and effectively protects BP nanosheets from oxidation under ambient condition. C 60 bonding leads to a rapid photoinduced electron transfer from BP to C 60 , affording enhanced photoelectrochemical and photocatalytic activities. The selective passivation of the reactive edge sites of BP nanosheets by sacrificial C 60 molecules paves the way toward ambient processing and applications of BP. Few-layered black phosphorus has unique and appealing electronic properties but is easily oxidized in air. Here, the authors covalently functionalize black phosphorus nanosheets with C 60 at their edges, providing improved stability and enhanced photoelectrochemical and photocatalytic activities.

Riemann surfaces are deformed versions of the complex plane in mathematics. Locally they look like patches of the complex plane, but globally, the topology may deviate from a plane. Nanostructured graphitic carbon materials resembling a Riemann surface with helicoid topology are predicted to have interesting electronic and photonic properties. However, fabrication of such processable and large π-extended nanographene systems has remained a major challenge. Here, we report a bottom-up synthesis of a metal-free carbon nanosolenoid (CNS) material with a low optical bandgap of 1.97 eV. The synthesis procedure is rapid and possible on the gram scale. The helical molecular structure of CNS can be observed by direct low-dose high-resolution imaging, using integrated differential phase contrast scanning transmission electron microscopy. Magnetic susceptibility measurements show paramagnetism with a high spin density for CNS. Such a π-conjugated CNS allows for the detailed study of its physical properties and may form the base of the development of electronic and spintronic devices containing CNS species. Fabrication of large π-conjugated carbon nanosolenoid materials with helicoid topology remains a challenge. Here the authors demonstrate synthesis of a metal-free π-extended carbon nanosolenoid material with a helical structure, exhibiting unique photophysical and magnetic properties.

Riemann surfaces inspired chemists to design and synthesize such multidimensional curved carbon architectures. It has been predicted that carbon nanosolenoid materials with Riemann surfaces have unique structures and novel physical properties. Here we report the first synthesis of a nitrogen-doped carbon nanosolenoid ( N-CNS ) using bottom-up approach with a well-defined structure. N-CNS was obtained by a rational Suzuki polymerization, followed by oxidative cyclodehydrogenation. The successful synthesis of N-CNS was fully characterized by GPC, FTIR, solid-state 13 C NMR and Raman techniques. The intrinsic single-strand molecular structures of N-CNS helices can be clearly resolved using low-dose integrated differential phase contrast scanning transmission electron microscopy (iDPC-STEM) technique. Possessing unique structural and physical properties, this long π-extended polymer N-CNS can provide new insight towards bottom-up syntheses of curved nanoribbons and potential applications as a metal-free photocatalyst for visible-light-driven H 2 evolution and highly efficient photocatalyst for photoredox organic transformations. Carbon nanosolenoid materials with Riemann surfaces have unique structures and novel physical properties. Here, the authors report a nitrogen-doped carbon nanosolenoid heterojunction material with distinctive photocatalytic properties for light driven hydrogen production and organic transformations.

Porous carbon materials play essential roles in electrocatalysis and electrochemical energy storage. It is of significant importance to rationally design and tune their porous structure and active sites for achieving high electrochemical activity and stability. Herein, we develop a novel approach to tune the morphology of porous carbon materials (PCM) by embedding fullerene C 60 , achieving improved performance of oxygen reduction reaction (ORR) and lithium-sulfur (Li-S) battery. Owing to the strong interaction between C 60 and imidazole moieties, pomegranate-like hybrid of C 60 -embedded zeolitic imidazolate framework (ZIF-67) precursor is synthesized, which is further pyrolyzed to form C 60 -embedded cobalt/nitrogen-codoped porous carbon materials (abbreviated as C 60 @Co-N-PCM). Remarkably, the unique structure of C 60 @Co-N-PCM offers excellent ORR electrocatalytic activity and stability in alkaline solutions, outperforming the commercial Pt/C (20 wt.%) catalyst. Besides, C 60 @Co-N-PCM as a novel cathode delivers a high specific capacity of ∼ 900 mAh·g −1 at 0.2 C rate in Li-S batteries, which is superior to the pristine ZIF-67-derived PCM without embedding C 60 .

Sonodynamic therapy (SDT) triggered by ultrasound represents an emerging tumor therapy approach with minimally invasive treatment featuring nontoxicity and deep tissue‐penetration, and its efficacy sensitively depends on the sonosensitizer which determines the generation of reactive oxygen species (ROS). Herein, for the first time covalently functionalized few‐layer black phosphorus nanosheets (BPNSs) are applied as novel sonosensitizers in SDT, achieving not only boosted SDT efficacy but also inhibited cytotoxicity relative to the pristine BPNSs. Three different covalently functionalized‐BPNSs are synthesized, including the first fullerene‐functionalized BPNSs with C60 covalently bonded onto the surface of BPNSs (abbreviated as C60‐s‐BP), surface‐functionalized BPNSs by benzoic acid (abbreviated as BA‐s‐BP), and edge‐functionalized BPNSs by C60 (abbreviated as C60‐e‐BP), and the role of covalent functionalization pattern of BPNSs on its SDT efficacy is systematically investigated. Except C60‐e‐BP, both surface‐functionalized BPNSs (C60‐s‐BP, BA‐s‐BP) exhibit higher SDT efficacies than the pristine BPNSs, while the highest SDT efficacy is achieved for BA‐s‐BP due to its strongest capability of generating the hydroxyl (·OH) radicals, which act as the dominant ROS to kill the tumor cells. Covalently functionalized few‐layer black phosphorus nanosheets (BPNSs), including surface‐functionalized BPNSs by benzoic acid (BA‐s‐BP) or C60 (C60‐s‐BP) and edge‐functionalized BPNSs by C60 (C60‐e‐BP), are applied as novel sonosensitizers in sonodynamic thearpy (SDT) for the first time, resulting in boosted SDT efficacy of BPNSs. BA‐s‐BP generates the highest amount of the hydroxyl (·OH) radicals to kill the tumor cells.

Metal carbido complexes bearing single-carbon-atom ligand such as nitrogenase provide ideal models of adsorbed carbon atoms in heterogeneous catalysis. Trimetallic μ 3 -carbido clusterfullerenes found recently represent the simplest metal carbido complexes with the ligands being only carbon atoms, but only few are crystallographically characterized, and its formation prerequisite is unclear. Herein, we synthesize and isolate three vanadium-based μ 3 -CCFs featuring V = C double bonds and high valence state of V (+4), including VSc 2 C@ I h (7)-C 80 , VSc 2 C@ D 5 h (6)-C 80 and VSc 2 C@ D 3 h (5)-C 78 . Based on a systematic theoretical study of all reported μ 3 -carbido clusterfullerenes, we further propose a supplemental Octet Rule, i.e., an eight-electron configuration of the μ 3 -carbido ligand is needed for stabilization of metal carbido clusters within μ 3 -carbido clusterfullerenes. Distinct from the classic Effective Atomic Number rule based on valence electron count of metal proposed in the 1920s, this rule counts the valence electrons of the single-carbon-atom ligand, and offers a general rule governing the stabilities of μ 3 -carbido clusterfullerenes. Trimetallic carbido clusterfullerenes (CCFs) represent the simplest metal carbido complexes with the ligands being only carbon atoms, but the formation prerequisite is unclear. Herein, the authors report the syntheses of three novel vanadium(V)-based CCFs featuring high vanadium valence state and propose a supplemental Octet Rule

[6,6]-Phenyl-C 61 -butyric acid methyl ester (PCBM), a star molecule in the fullerene field, has found wide applications in materials science. Herein, electrosynthesis of buckyballs with fused-ring systems has been achieved through radical α-C−H functionalization of the side-chain ester for both PCBM and its analogue, [6,6]-phenyl-C 61 -propionic acid methyl ester (PCPM), in the presence of a trace amount of oxygen. Two classes of buckyballs with fused bi- and tricyclic carbocycles have been electrochemically synthesized. Furthermore, an unknown type of a bisfulleroid with two tethered [6,6]-open orifices can also be efficiently generated from PCPM. All three types of products have been confirmed by single-crystal X-ray crystallography. A representative intramolecularly annulated isomer of PCBM has been applied as an additive to inverted planar perovskite solar cells and boosted a significant enhancement of power conversion efficiency from 15.83% to 17.67%. [6,6]-Phenyl-C 61 -butyric acid methyl ester (PCBM), a star molecule in the fullerene field, has found wide applications in materials science. Here, the authors demonstrate the synthesis of buckyballs with fused-ring systems via electrosynthesis through radical α-C−H functionalization of the side-chain ester for both PCBM and its analogue.

Because of the limitations of traditional refrigerants, the application of trans-critical CO2 technology in domestic gas conditioners and other fields is becoming increasingly popular. This paper proposes a new CO2 trans-critical refrigeration system. Combining the internal heat exchanger and expander components, as well as the two-stage compression cycle, we analyzed the effectiveness of the expander, internal heat exchanger, and intercooling on system performance under various operating conditions in terms of energy, exergy analysis, and optimal discharge pressure. The system performance can be changed by changing the cycle conditions and internal heat exchanger effectiveness, which reduces system power consumption and the percentage of exergy losses of gas cooler components. Compared to the single-stage compression with expander cycle, the systems cycle power consumption is reduced by 2–15.7% and the maximum system COP is increased by 2.93–6.93%. From the view of energy effectiveness, the system’s maximum COP increases by 3.9% and the percentage of exergy losses of gas cooler decreases by 22.5% with the effectiveness of internal heat exchanger varying. The addition of an internal heat exchanger has resulted in improved system performance, which is important for providing a relevant cycle model for the application.