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The inherent shortcomings of a zinc anode in aqueous zinc‐ion batteries (ZIBs) such as zinc dendrites and side reactions severely limit their practical application. Herein, to address these issues, an ion‐oriented transport channel constructed by graphdiyne (GDY) nanowalls is designed and grown in situ on the surface of a zinc electrode. The vertically stacked GDY nanowalls with a unique hierarchical porous structure and mechanical properties form a nanomesh‐like interface on the zinc electrode, acting as an ion‐oriented channel, which can efficiently confine the segmented growth of zinc metal in microscopic regions of hundreds of nanometers. In those microscopic regions, the uniform domain current density is effortlessly maintained compared with a large surface area, thereby inhibiting zinc dendrites effectively. Besides, due to the presence of the ion‐oriented channel, the modified zinc anode demonstrates long‐term stable zinc plating/stripping performance for more than 600 h at 1 mAh cm−2 in an aqueous electrolyte. In addition, full‐cells coupled with MnO2 show high specific capacity and power density, as well as excellent cycling stability with a capacity retention of 82% after 5000 cycles at 1 A g−1. This work provides a feasible and accessible surface engineering approach to modify the electrode interface for confined and dendrite‐free zinc deposition in aqueous ZIBs. [ABSTRACT FROM AUTHOR]

Carbyne delivers various excellent properties for the existence of the larger number of sp‐hybridized carbon atoms. Here, a 3D well‐defined porous carbon material germanium‐carbdiyne (Ge‐CDY) which is comprised of only sp‐hybridized carbon atoms bridging by Ge atoms has been developed and investigated. The unique diamond‐like structure constructed by linear butadiyne bonds and sp3‐hybridized Ge atoms ensures the stability of Ge‐CDY. The large percentage of conjugated alkyne bonds composed of sp‐C guarantees the good conductivity and the low band gap, which were further confirmed experimentally and theoretically, endowing Ge‐CDY with the potential in electrochemical applications. The well‐defined 3D carbon skeleton of Ge‐CDY provides abundant uniform nanopores, which is suitable for metal ions storage and diffusion. Further half‐cell evaluation also demonstrated Ge‐CDY exhibited an excellent performance in lithium storage. All those indicating sp‐hybridized carbon‐based materials can exhibit great potential to possess excellent properties and be applied in the field of energy, electronic, and so on. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Graphdiyne (GDY), as a new carbon material with two‐dimensional structure composed by sp2 and sp carbon atoms, has exhibited excellent properties in various fields due to its conjugated pore structure, high specific surface area and stable structure. Various properties can also be tuned through the adjustability of the electronic structure by chemical methods. This article systematically discusses the preparation methods and strategies of GDY and GDY based materials. These preparation methods provide the way for us to obtain various GDY materials targeting specific research and application. [ABSTRACT FROM AUTHOR]

Regarding different kinds of alkali metal ion batteries such as lithium‐ion battery (LIB), sodium‐ion battery (NIB), and potassium‐ion battery (KIB), since the diameters and properties of these ions are different, there are few materials that are adaptable simultaneously as the anode for these batteries. To achieve the versatile compatibility material, its chemical component and spatial configuration need to be predesigned for possessing abundant storage sites and efficient diffusion paths. Here, a well‐designed 3D material silicon‐diamondyne (Si‐DY) is prepared which is only comprised of butadiyne units and sp3‐hybridized silicon atoms. Owing to the combination of the abundant diyne and various inner channels in the stable diamond‐like skeleton, Si‐DY exhibits excellent storage and diffusion properties for alkali metal ions. The Si‐DY is predicted with an ultrahigh theoretical capacity of 3674, 2810, and 1945 mAh g−1 for lithium, sodium, and potassium ions, respectively. Especially, as the anode of LIB, NIB, and KIB, Si‐DY achieves very high stable practical specific capacities of 2350, 812, and 512 mAh g−1, respectively, as well as an ultra‐long cycling stability. Those outstanding results demonstrate that the as‐designed Si‐DY displays an exceptional potential as the versatile material for energy applications. [ABSTRACT FROM AUTHOR]

Zero valence palladium (Pd(0)) nanoparticles have been reported to be more favorable to the oxygen reduction reaction (ORR) than palladium oxide (PdO). However, PdO is normally concomitant in Pd(0) nanoparticles. Herein, we developed an inventive method to prepare pure Pd(0) nanoparticles supported with hydrogen-substituted graphyne (Pd/HsGY) and its nitrogen-doped sample (Pd/N–HsGY). Pd(0) nanoparticles were obtained by reducing the atomically dispersed bivalent Pd, which is easy to be anchored on HsGY. The unique sp-hybridized carbon atoms in HsGY exhibited obvious extrinsic charge compensation to maintain the supported Pd nanoparticles to zero valence state. The as-prepared samples, especially Pd/N–HsGY, displayed excellent activity for ORR, higher than that of commercial Pd/C and Pt/C. In an alkaline medium, the mass activity of Pd/N–HsGY at 0.8 V (vs. RHE) was 2.1 times higher than that of Pd/C, and 1.7 times higher than that of Pt/C. While in an acidic medium, the mass activity of Pd/N–HsGY was 17.7 and 1.6 times Pd/C and Pt/C, respectively. Pd/N–HsGY based Zn–air battery exhibited higher power density than Pt/C-based battery and superior stability for more than 300 hours. Density functional theory calculations confirmed that Pd(0) nanoparticles, Pd/HsGY and Pd/N–HsGY were favorable to ORR. This method brings new perspectives for designing zero valence metal nanoparticles for electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal anodes exhibit intriguing advantages for application in high‐energy‐density batteries. However, the short cycle life and security issues of these anodes induced by the dendrite growth and huge volumetric change of Li severely limit their practical application. Herein, a heuristic method to fabricate a self–supported seaweed‐like Li metal anode directly to improve the cycle life of Li metal batteries, is reported. The unique seaweed‐like morphology of the Li anode facilitates the dispersion of the local current density, impeding the uneven growth of Li dendrites, and remits the volume expansion of the anode, leading to excellent cycle performance. The as‐prepared Li metal anode exhibits excellent plating–stripping stability over 600 cycles at high current density of 2 mA cm−2 and delivers excellent stability even with the Li4Ti5O12 cathode in the full cell. This study provides a facile strategy to prepare stable and dendrite‐free Li anodes by controlling the morphology of Li metal. Thus, this study can further inspire new research ideas for preparing stable Li metal anodes. [ABSTRACT FROM AUTHOR]

Developing new electrode materials with a regular channel for stable storage and diffusion of potassium (K) ions is crucial to alleviating the ubiquitous problems in K‐ion batteries (KIBs) such as slow diffusion rate, huge volume expansion, and unstable interface by the large K ion radius. Herein, electrode material with a facile diffusion pathway, vast space for volume expansion, and good interfacial compatibility are found to be necessary. Fluoride graphdiyne (F‐GDY) is illustrated for its expanded conductive skeleton, uniform structural pores, and well‐distributed F atoms. First‐principles computations and electrochemical characterizations reveal the high reversible capacity and cyclic stability for the instanced F‐GDY electrode through the ultralow diffusion barrier, abundant exposed active sites, and stable KF‐enriched solid electrolyte interphase film. The F‐GDY anode exhibits a capacity of 320 mAh g−1 at 50 mA g−1, and 120 mAh g−1 at 1000 mA g−1 for 1800 cycles. These electrochemical performances of F‐GDY anode are superior than those of many other carbon materials reported to date, providing us with a new insight into the design of an electrode for KIBs. [ABSTRACT FROM AUTHOR]

Graphdiyne as a new allotrope of carbon material was constructed by benzene rings and butadiyne. The large 2D conjugated structure endows graphdiyne with excellent conductivity and flexibility. More importantly, the atomic arrangement of graphdiyne with a unique porous framework structure is very different from the compact structure of other carbon materials, such as graphene and carbon nanotubes. This is of great benefit to the diffusion and transfer of ions and gases. In the meantime, the high specific surface area originating from the pore structure can also provide abundant active sites for the storage of electrons or ions. The high charge density around the acetylenic bond in graphdiyne supplies the adsorption capacity of ions and gases as well as the catalytic ability to some degree. In addition, the mild synthetic route endows graphdiyne with function tunability and good film-forming ability. Benefiting from all these extraordinary properties, graphdiyne would have a bright future for applications in electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Graphyne and its derivatives, with a unique sp–sp2 hybridized structure and interesting electronic properties, are predicted to be attractive carbon materials for many practical applications. Here we report well-defined hydrogen substituted graphyne (HsGY) prepared using a facile bottom-up approach with a large area of up to 33 cm2. Studied directly by HRTEM, selected area electron diffraction and corresponding simulation, the as-synthesized crystalline HsGY nanosheets showed AB stacking with a lattice fringe of 0.445 nm. The aromatic C–H bonds and the acetylene linkages of HsGY provide a large number of active sites for ion binding; the high specific surface area, wide interlayer spacing, hierarchical porous structure, excellent electronic conductivity and low carrier barrier of HsGY also guarantee excellent intercalation and diffusion of sodium ions, making HsGY a promising anode for rechargeable batteries. Theoretical calculations demonstrate that the porous HsGY can provide numerous storage sites and deliver a theoretical capacity larger than 1207 mA h g−1. The prepared HsGY electrodes delivered a high reversible capacity of 600 mA h g−1 at a current density of 100 mA g−1; even at a high current density of 5000 mA g−1, the as-prepared HsGY electrodes can deliver a stabilized capacity of 320 mA h g−1 for 5900 cycles, with an excellent capacity retention of 96%. [ABSTRACT FROM AUTHOR]

Lithium‐ion capacitors (LICs) have shown extraordinary promise for electrochemical energy storage but are usually limited to electrodes with low energy density or power density owing to the lack of active storage sites and ion diffusion limitation. In this study, fluorine‐enriched graphdiyne (F‐GDY) is prepared by a solvothermal reaction. Owing to the 42‐C hexagonal porous structure, abundant sp and sp2 hybrid carbon atoms, and even distribution of fluorine, F‐GDY has enormous potential as an anode for lithium‐ion storage. The outstanding rate performance (1825.9 mAh g−1 at 0.1 A g−1, 979.2 mAh g−1 at 5 A g−1) and stable cycling stability of F‐GDY in the lithium‐ion battery inspire the assembly of a LIC with F‐GDY as an anode and activated carbon (AC) as a cathode. When the AC/F‐GDY mass ratio is 7:1, the LIC gives the largest energy density of 200.2 Wh kg−1, corresponding to a power density of 131.17 W kg−1. This LIC also shows excellent long‐term cycling stability with a retention of approximately 80 % after 5000 cycles at 2 A g−1 and a retention of more than 80 % after 6000 cycles at 5 A g−1. LIC it up: A lithium‐ion capacitor (LIC) with a fluorine‐enriched graphdiyne anode is synthesized by a solvothermal reaction and displays higher energy and power densities than many carbon materials. The LIC gives a high energy density of 200.2 Wh kg−1, corresponding to a power density of 131.17 W kg−1 and shows excellent long‐term cycling stability. [ABSTRACT FROM AUTHOR]

On account of the high‐cost of platinum, researchers are working to develop a new catalyst that is cheaper and has a catalytic effect equivalent to platinum. Herein, owing to the unique acetylenic bonds in graphdiyne, iron, nitrogen co‐doped graphdiyne (Fe‐N‐GDY) is a promising nonprecious metal catalyst, which has been developed with just a small amount of iron precursor with the plan to substitute it for Pt‐based catalysts. The as‐synthesized Fe‐N‐GDY composited catalyst shows excellent catalytic performance with the onset potential of 0.94 V versus reversible hydrogen electrode and limited current density of 5.4 mA cm−2. Moreover, it shows excellent resistance to methanol poisoning and stability in both acidic and alkaline electrolytes, which makes potentially applicable in the oxygen reduction reaction field. Doped graphdiyne: An efficient nonprecious metal electrocatalyst is synthesized by using novel graphdiyne (GDY) materials for the oxygen reduction reaction. Owing to the powerful synergistic effect between Fe, N, and GDY, the Fe‐N co‐doped GDY (Fe‐N‐GDY) catalyst has excellent catalytic activity in both alkaline and acidic media, comparable to Pt/C. Moreover, the stability and methanol tolerance of Fe‐N‐GDY are better than those of Pt/C. [ABSTRACT FROM AUTHOR]

Abstract: Nitrogen‐doped graphdiyne (N‐GDY) is prepared through the nitriding of graphdiyne (GDY) under ammonia. This material possesses excellent ability for the fast diffusion and storage of lithium and sodium ions due to its high conductivity, wide interlayer distance, unique three‐dimensional porous structure, and associated defects from nitrogen doping. The lithium‐ion capacitor (LIC) and sodium‐ion capacitor (SIC) fabricated with N‐GDY as the negative electrode show outstanding electrochemical performance, especially having both high power density and energy density. Besides exhibiting an energy density of 174 Wh kg−1, the N‐GDY‐based LIC can still offer an energy density of 107 Wh kg−1 even at a power density of 11250 W kg−1, whereas the N‐GDY‐based SIC can retain an energy density of 119 Wh kg−1 at a power density of 22500 W kg−1. The energy densities of N‐GDY‐based LIC and SIC are higher than those of pure GDY and many other carbon materials. [ABSTRACT FROM AUTHOR]

Abstract: Boron‐graphdiyne (BGDY), which has a unique π‐conjugated structure comprising an sp‐hybridized carbon skeleton and evenlydistributed boron heteroatoms in a well‐organized 2D molecular plane, is prepared through a bottom‐up synthetic strategy. Excellent conductivity, a relatively low band gap and a packing mode of the planar BGDY are observed. Notably, the unusual bonding environment of the all sp‐carbon framework and the electron‐deficient boron centers generates affinity to metal atoms, and thus provides extra binding sites. Furthermore, the expanded molecule pores of the BGDY molecular plane can also facilitate the transfer of metal ions in the perpendicular direction. The practical effect of the all sp‐carbon structure and boron heteroatoms on the properties of BGDY are demonstrated in its performance as the anode in sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Large‐area graphdiyne film is constructed by heat treatment, including thermally induced evaporation and a cross‐coupling reaction process. The growth mechanism is proposed based on the observation and characterization that the heating temperature plays an important role in the evaporation of oligomers and in triggering the thermal cross‐coupling reaction, whereas the heating duration mainly determines the execution of the thermal cross‐coupling reaction. By controlling the heat‐treatment process, a graphdiyne film with uniform morphology and good conductivity is obtained. The improved GDY film based electrodes deliver good interfacial contact and more lithium storage sites; thus leading to superior electrochemical performance. A reversible capacity of 901 mAh g−1 is achieved. Specifically, the electrodes exhibit excellent rate performance, with which a capacity of 430 mAh g−1 is maintained at a rate as high as 5 A g−1. These advantages mean that the uniform graphdiyne film is a good candidate for the fabrication of a flexible and high‐capacity electrode material. [ABSTRACT FROM AUTHOR]

Chlorine-substituted graphdiyne (Cl-GDY) is prepared through a Glaser-Hay coupling reaction on the copper foil. Cl-GDY is endowed with a unique π-conjugated carbon skeleton with expanded pore size in two dimensions, having graphdiyne-like sp- and sp2- hybridized carbon atoms. As a result, the transfer tunnels for lithium (Li) ions in the perpendicular direction of the molecular plane are enlarged. Moreover, benefiting from the bottom-to-up fabrication procedure of graphdiyne and the strong chemical tailorability of the alkinyl-contained monomer, the amount of substitutional chlorine atoms with appropriate electronegativity and atom size is high and evenly distributed on the as-prepared carbon framework, which will synergistically stabilize the Li intercalated in the Cl-GDY framework, and thus generate more Li storage sites. Profiting from the above unique structure, Cl-GDY shows remarkable electrochemical properties in lithium ion half-cells. [ABSTRACT FROM AUTHOR]

Sn-based sulfides are potential anode materials for lithium-ion batteries (LIBs); nevertheless, they typically suffer from poor cycle stability resulted from the huge volume variation during lithium-ion insertion and extraction. Herein, we successfully fabricated the multiphase Cu2Sn3S7/Cu2SnS3/SnS2 (CTS) submicron spheres uniformly incorporated with reduced graphene oxide nanosheets (CTS@RGO). This binder-free hybrid CTS@RGO paper exhibits favorable capacity retention as an anode of LIBs (965 mAh g−1 after 300 cycles at current density of 500 mA g−1), as well as better rate capability and high initial coulombic efficiency compared with that of a pristine CTS anode. The enhanced electrochemical performance can be ascribed to the introduction of graphene as a buffer to accommodate large volume changes and to maintain structural integrity of electrode. [ABSTRACT FROM AUTHOR]

Sodium ion batteries have gained recognition as an intriguing candidate for next generation battery systems and large scale energy storage devices due to the natural abundance of sodium sources. In this study, we prepared bulk graphdiyne powder with a porous structure and explored its sodium storage properties. The assembled sodium ion batteries exhibited extraordinary electrochemical performance, including moderate specific capacity, long cycle life as well as excellent rate performance, which should be attributed to its unique three-dimensional porous structure, chemical stability and high electronic conductivity. We obtained a reversible capacity of 261 mA h g−1 after 300 cycles at a current density of 50 mA g−1. Even at a high current density of 100 mA g−1, the as-prepared GDY electrodes delivered a moderate specific capacity of 211 mA h g−1 after 1000 cycles, with an excellent capacity retention of 98.2%. The calculation results indicate that most intercalated Na cations stay in a large triangular hole in bulk material. [ABSTRACT FROM AUTHOR]