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Modulating the electronic structure of electrode materials at atomic level is the key to controlling electrodes with outstanding rate capability. On the basis of modulating the iron cationic vacancies (IV) and electronic structure of materials, we proposed the method of preparing graphdiyne/ferroferric oxide heterostructure (IV‐GDY‐FO) as anode materials. The goal is to motivate lithium‐ion batteries (LIBs) toward ultra‐high capacity, superior cyclic stability, and excellent rate performance. The graphdiyne is used as carriers to disperse Fe3O4 uniformly without agglomeration and induce high valence of Fe with reducing the energy in the system. The presence of Fe vacancy could regulate the charge distribution around vacancies and adjacent atoms, leading to facilitate electronic transportation, enlarge the lithium‐ion diffusion, and decrease Li+ diffusion barriers, and thus displaying significant pseudocapacitive process and advantageous lithium‐ion storage. The optimized electrode IV‐GDY‐FO reveals a capacity of 2084.1 mAh g−1 at 0.1 C, superior cycle stability and rate performance with a high specific capacity of 1057.4 mAh g−1 even at 10 C. [ABSTRACT FROM AUTHOR]

A multi‐level architecture formed alternatively by the conformal graphdiyne (GDY) and CuS is well engineered for Li‐free cathode. Such a proof‐of‐concept architecture efficiently integrates the advantages of GDY and produces new functional heterojunctions (sp−C−S−Cu hybridization bond). The layer‐by‐layer 2D confinement effect successfully avoids structural collapse, the selective transport inhibits the shuttling of active components, and the interfacial sp−C−S−Cu hybridization bond significantly regulates the phase conversion reaction. Such new sp−C−S−Cu hybridization of GDY greatly improves the reaction dynamics and reversibility, and the cathode delivers an energy density of 934 Wh kg−1 and an unattenuated lifespan of 3000 cycles at 1 C. Our results indicate that the GDY‐based interface strategy will greatly promote the efficient utilization of the conversion‐type cathodes. [ABSTRACT FROM AUTHOR]

The development of catalysts that can selectively and efficiently promote the alkene epoxidation at ambient temperatures and pressures is an important promising path to renewable synthesis of various chemical products. Here we report a new type of zerovalent atom catalysts comprised of zerovalent Ir atoms highly dispersed and anchored on graphdiyne (Ir0/GDY) wherein the Ir0 is stabilized by the incomplete charge transfer effect and the confined effect of GDY natural cavity. The Ir0/GDY can selectively and efficiently produce styrene oxides (SO) by electro-oxidizing styrene (ST) in aqueous solutions at ambient temperatures and pressures with high conversion efficiency of ∼100%, high SO selectivity of 85.5%, and high Faradaic efficiency (FE) of 55%. Experimental and density functional theory (DFT) calculation results show that the intrinsic activity and stability due to the incomplete charge transfer between Ir0 and GDY effectively promoted the electron exchange between the catalyst and reactant molecule, and realized the selective epoxidation of ST to SO. Studies of the reaction mechanism demonstrate that Ir0/GDY proceeds a distinctive pathway for highly selective and active alkene-to-epoxide conversion from the traditional processes. This work presents a new example of constructing zerovalent metal atoms within the GDY matrix toward selective electrocatalytic epoxidation. [ABSTRACT FROM AUTHOR]

Owing to unique alkyne‐rich structure, graphdiyne (GDY) has been proven to be a superb support for anchoring metal catalysts. Herein we demonstrate a new role of GDY as the wettability modifier for enhanced hydrogenation catalysis. After loading a certain amount GDY nanospheres, the silica mesoporous channels become superaerophilic, which allows gaseous H2 to be directly stored inside, thus significantly increasing the H2 concentration around the palladium nanoparticles (NPs). At the same time, GDY nanospheres also alter the electronic structure of the Pd NPs via a strong d‐π interaction. Combining these two roles of GDY, allows the hydrogenation of benzaldehyde to proceed under ambient H2 pressure in water, with an impressive 4.3‐fold enhancement compared to the unmodified Pd/mSiO2 catalyst. This study demonstrates a new role of GDY in constructing wettability matched catalysts for gas‐liquid‐solid tri‐phase reactions. [ABSTRACT FROM AUTHOR]

Tailorable electron distribution of the active sites is widely regarded as the key issue to boost the catalytic activity and provide mechanistic insights into the structure–property–performance relationship. Here, a selective metal atom in situ growth strategy to construct highly active interface of mixed metal atom with different NbyRhOx species on sp‐/sp2‐cohybridized graphdiyne (NbyRhOx/GDY) is reported. With this innovative idea implemented, experimental results show that the asymmetric electron distribution and the variation of coordination environment of bimetallic species significantly improve the electrocatalytic activity of NbyRhOx/GDY. Optimal hydrogen evolution reaction (HER) activity is achieved at the Nb/Rh ratio of 0.23, exhibiting excellent HER activity with the small overpotentials of 14 and 10 mV at 10 mA cm−2 in alkaline and neutral electrolytes. The data show the strong potential for real‐system application of such catalysts, which outperform commercial Pt/C (20 wt%). These results shown in this study represent a platform for designing novel catalytic materials by selectively introducing metal atoms on different supports, which can be used as a general method extended to other catalytic systems. [ABSTRACT FROM AUTHOR]

Rational design and synthesis of non‐precious metal‐based electrocatalysts for efficient overall water splitting (OWS) in an integrated electrolyzer are of great significance for the development of hydrogen energy. To this end, nanowire‐structured heterogenous MnCo2O4/graphdiyne arrays are synthesized on the surface of 3D carbon cloth (NW‐MnCo2O4/GDY) by using in situ assembly and coupling strategy. Experiments demonstrated that the special core/shell‐nanowire structure and synergistic interaction between the MnCo2O4 and GDY can greatly improve the electric conductivity, facilitate the mass/ion transport and gas emissions, expose more active sites, and thus lead to the enhancement of the catalytic activity and long‐term stability of the electrocatalysts for OWS. For example, the alkaline water electrolyzer assembled by NW‐MnCo2O4/GDY shows high‐performance with only 1.47 and 1.60 V required to reach a current density of 10 and 100 mA cm−2, respectively, which is even better than that of previously reported electrocatalysts. [ABSTRACT FROM AUTHOR]

There is no doubt that hydrogen energy can play significant role in promoting the development and progress of modern society. The utilization of hydrogen energy has developed rapidly, but it is far from the requirement of human. Therefore, it is very urgent to develop methodologies and technologies for efficient hydrogen production, especially high activity and durable electrocatalysts. Here a bimetallic oxide cluster on heterostructure of vanadium ruthenium oxides/graphdiyne (VRuOx/GDY) is reported. The unique acetylene‐rich structure of graphdiyne achieves outstanding characteristics of electrocatalyst: i) controlled preparation of catalysts for achieving multiple‐metal clusters; ii) regulation of catalyst composition and morphology for synthesizing high‐performance catalysts; iii) highly active and durable hydrogen evolution reaction (HER) properties. The optimal porous electrocatalyst (VRu0.027Ox/GDY) can deliver 10 mA cm−2 at low overpotentials of 13 and 12 mV together with robust long‐term stability in alkaline and neutral media, respectively, which are much smaller than Pt/C. The results reveal that the synergism of different components can efficiently facilitate the electron/mass transport properties, reduce the energy barrier, and increase the active site number for high catalytic performances. [ABSTRACT FROM AUTHOR]

Efficient acidic water oxidation utilization in the oxygen evolution reaction (OER) is still an important bottleneck for hydrogen production. From fundamental principles, a controllable graphdiyne (GDY) induced growth strategy is established; highly uniform size distribution of oxidized iridium quantum dots is prepared on the surface of graphdiyne (IrOxQD/GDY). The result shows that, the catalyst exhibits excellent activity and durability for acidic OER, with a current density of 10 mA cm−2 at a small overpotential of 236 mV versus the reversible hydrogen electrode (RHE) and a Tafel slope of 70 mV dec−1. The performance is greatly superior to previously reported electrocatalysts. Remarkably, the acidic electrolyzer using IrOxQD/GDY as both cathode and anode electrodes can reach 10 mA cm−2 only at a much low cell voltage of 1.49 V (vs RHE). The results show the superior advantages of graphdiyne in effectively increasing numbers of the catalytically active sites for improving the charge transfer behavior and protecting the metal catalysts from corrosion. [ABSTRACT FROM AUTHOR]

We utilize the domain-limiting effect of the porous graphdiyne (GDY) hexagonal ring to control synthesis of single-nickel-atom-alloyed platinum hexagonal nanocrystals (NiPtSAA/GDY) with uniform size approximate to 2.18 nm and atomically lattice distortion. The structure of NiPtSAA/GDY was confirmed by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and detail characterized and theoretical calculations. The hexagonal nanocrystals showed an excellent mass activity of 4.40 A mg Pt+Ni −1 and specific activity (136.78 mA cm−2) and exhibited the greatly enhancement in the durability and activity in MOR. In situ XAFS and XPS measurements indicated that low valence states of Pt in NiPtSAA/GDY were highly resistant to CO poisoning and demonstrated that the valence states were the origin of the activity. Our results provide a solid foundation for the design and synthesis with high dependence on valence and reactivity, while avoiding synergistic CO-poisoning, and also provide a general route for the design of new model catalysts. [Display omitted] • Single-nickel-atom-alloyed platinum hexagonal nanocrystal shows high activity, selectivity and durability for MOR. • The NiPtSAA/GDY shows high mass activity of 4.40 A mg Pt+Ni −1 and specific activity of 136.78 mA cm−2 for MOR. • We report a general and efficient strategy for fabricated the new model catalysts. [ABSTRACT FROM AUTHOR]

Over the years, scientists have sought to pursue ammonia (NH 3) production, and have tried to bring huge transform and benefits for renewable energy technologies to replace high-pollution and energy-consuming Haber-Bosh processes. Here we would like to launch a novel catalyst of porous graphdiyne (GDY) based quantum dots for ammonia production. The ultra-high catalytic performance is origin from the rapid conversion of valence states of metal element within the catalyst and the great enhancement of surface plasmon resonance (SPR). This highly compatible synergistic effect enables excellent photocatalytic performance. After 46 independent experiments, a highest NH 3 yield rate (Y NH3) of 26502 μmol NH3 g cat. −1 h−1, a lowest Y NH3 of 15026 μmol NH3 g cat. −1 h−1, and an average Y NH3 of 19583 μmol NH3 g cat. −1 h−1 in 46 independent experiments were respectively given, as well as the high long-term stability. A novel catalyst of porous graphdiyne (GDY) based quantum dots was precisely synthesized for photocatalyzed ammonia production. The strong advantages of graphdiyne could effectively regulate photocatalytic activity and coordination environments and great enhance the surface plasmon resonance (SPR) effect, which enables excellent NH 3 yield rate and high long-term stability. [Display omitted] • A novel catalyst of porous graphdiyne based quantum dots was precisely synthesized for photocatalyzed ammonia production. • Graphdiyne effectively regulates the coordination environments and the surface plasmon resonance effect of the catalysts. • The unique properties of the catalyst endow it with excellent NH3 yield rate and high long-term stability. [ABSTRACT FROM AUTHOR]

Keywords: graphdiyne; heterostructures; iridium oxides; oxygen evolution reaction; quantum dots EN graphdiyne heterostructures iridium oxides oxygen evolution reaction quantum dots 1 1 1 08/28/21 20210826 NES 210826 B Quantum Dots b In article number 2101138, Yurui Xue, Feng He, Yuliang Li and co-workers demonstrate controllable growth of iridium oxide quantum dots by exploiting the unique properties of graphdiyne. Graphdiyne, heterostructures, iridium oxides, oxygen evolution reaction, quantum dots This provides an ideal system to control the preparation of small size, quantum dot catalysts, fully demonstrating the size and quantum effects of these catalysts in the catalytic process, and obtaining highly active and robust catalysts with excellent acidic water oxidation performance. [Extracted from the article]

• A graphdiyne-based anodic nanochannel is constructed for direct methanol fuel cell. • The methanol electrooxidation is efficiently confined in the ordered nanochannels. • Proton selectivity of the nanochannels suppress 33% methanol crossover. • Such electrode benefits the utilization efficiency of the noble metals in fuel cell. A free-standing graphdiyne-based anodic electrode with ordered nanotubes is fabricated in large scale, in which the robust PtCu alloy catalysts are well anchored on the inside wall. The confined methanol electrooxidation in the nanotubes and the proton selectivity of graphdiyne suppress 33% methanol crossover, therefore achieving a high performance and durability in the direct methanol fuel cell. [Display omitted] A large area of freestanding graphdiyne films with an independent anode array of GDY@PtCu was prepared. Structural analysis confirmed that electroactive Pt 4.4 Cu alloy nanoparticles with a diameter size of 4.2 nm, which can be anchored on the inner wall of the GDY nanochannel. This highly active anodic electrode demonstrates intrinsic selectivity and efficient suppression of methanol crossover and achieves selective proton transport in the electrode, due to GDY special surface and super-large pore structure. Our results show that, in this process, the methanol diffusion pathway is highly ordered, methanol electrooxidation is effectively confined in ordered GDY nanochannels. As-prepared GDY@PtCu anode not only demonstrated superior electrocatalytic activity and duration, at the same time, the utilization efficiency of catalyst and methanol fuel is greatly improved. A DMFC using such an anodic electrode material exhibits superior power density of 90 mW cm-2 at 80 °C with an ultralow Pt loading (0.8 mg cm-2) and the methanol crossover is greatly suppressed up to 33%. After a 500 h long-term testing, the DMFC based-on freestanding GDY@PtCu anode still maintains high retention (81%) of its original power density. [ABSTRACT FROM AUTHOR]

The inhabitation of lithium dendrites growth was very important for the safety of lithium battery. Coating the lithium battery negative electrode by a thin film with proper channels can inhibit the growth of lithium dendrites through tuning the transportation rate of lithium ions. This work showed that the introduction of proper substituents into graphdiyne (GDY) can change the coordination environment of the diyne groups with the metal ions, thus the benefits of cation-π interactions and the intrinsic channels formed in GDY can be combined to tune the ion conduction and atomic-level selective transport, which can protect the electrode structure, inhibit side reactions at the interface, inhibit the shuttle of active materials, and even adjust the electrode performance. Combined with theory calculation, solution studies of the model compound toward lithium ions revealed the ion binding sites of this benzene substituted graphdiyne. The lithium battery with negative electrode coated with Ben-GDY film has long cycle (over 800 h) stability at current densities of 1 mAh cm−2 and 0.5 mAh cm−2. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Bottom-up synthesis of N-doped Graphdiyne (NGDY) gives accurate nitrogen species and content. • Metal nanoparticles (Pt, Pd, Ni, Cu) supported on NGDY show obvious charge transfer from the substrate. • Pd-NGDY catalyst is active towards Suzuki-Miyaura reaction. • DFT calculations disclose a unique free energy route of the reaction process. For heterogeneous catalysts with nitrogen doped carbon materials as supporting substrates, accurate nitrogen (N) species and content is an important factor for promoting the catalytic activity. In this paper, N-doped graphdiyne (NGDY) was prepared from tetraethynylpyrazine (TEP) by bottom-up synthesis method as the support of metal nanoparticles. Specific pyridine nitrogen atoms are introduced in the N-doped carbon material. This unique structure makes it a promising material to support ultrafine metal particles or clusters. Microwave-assisted anchoring of Pd, Pt, Cu, Ni nanoparticles on NGDY generated novel hybrid composites, in which Pd-NGDY has high versatility for Suzuki-Miyaura reaction. DFT calculations revealed a charge transfer from NGDY to Pd NPs, and the free energy distribution showed a downward trend for Suzuki-Miyaura coupling reactions. [ABSTRACT FROM AUTHOR]