Graphdiyne (GDY), a newly emerging 2D carbon allotrope, has been widely explored in various fields owing to its outstanding electronic properties such as the intrinsic bandgap and high carrier mobility. Herein, GDY‐based photoelectrochemical‐type photodetection is realized by spin‐coating ultrathin GDY nanosheets onto flexible poly(ethylene terephthalate) (PET) substrates. The GDY‐based photodetectors (PDs) demonstrate excellent photo‐responsive behaviors with high photocurrent (Pph, 5.98 µA cm‐2), photoresponsivity (Rph, 1086.96 µA W‐1), detectivity (7.31 × 1010 Jones), and excellent long‐term stability (more than 1 month). More importantly, the PDs maintain an excellent Pph after 1000 cycles of bending (4.45 µA cm‐2) and twisting (3.85 µA cm‐2), thanks to the great flexibility of the GDY structure that is compatible with the flexible PET substrate. Density functional theory (DFT) calculations are adopted to explore the electronic characteristics of GDY, which provides evidence for the performance enhancement of GDY in alkaline electrolyte. In this way, the GDY‐based flexible PDs can enrich the fundamental study of GDY and pave the way for the exploration of GDY heterojunction‐based photodetection.

A graphdiyne-based artificial synapse (GAS), exhibiting intrinsic short-term plasticity, has been proposed to mimic biological signal transmission behavior. The impulse response of the GAS has been reduced to several millivolts with competitive femtowatt-level consumption, exceeding the biological level by orders of magnitude. Most importantly, the GAS is capable of parallelly processing signals transmitted from multiple pre-neurons and therefore realizing dynamic logic and spatiotemporal rules. It is also found that the GAS is thermally stable (at 353 K) and environmentally stable (in a relative humidity up to 35%). Our artificial efferent nerve, connecting the GAS with artificial muscles, has been demonstrated to complete the information integration of pre-neurons and the information output of motor neurons, which is advantageous for coalescing multiple sensory feedbacks and reacting to events. Our synaptic element has potential applications in bioinspired peripheral nervous systems of soft electronics, neurorobotics, and biohybrid systems of brain–computer interfaces.

As a rising star of all‐carbon nanomaterial, graphdiyne (GDY) has a direct natural bandgap and features strong light–matter interaction, large optical absorption, superior chemical and optical stability, indicating its broad prospects in the field of photonics and optoelectronics. Herein, the broadband nonlinear absorption and transient absorption characteristics of GDY from visible to infrared region has been studied for the first time, and its promising application in ultrafast photonics has been explored. The large nonlinear absorption coefficient (> −1 cm GW−1), low saturation intensity (<13 GW cm−2), and ultrafast relaxation time (<30 ps) of GDY are demonstrated, which indicates the outstanding potential of GDY in photonics among the emerging novel nonlinear optical (NLO) materials. The GDY is mixed with polyvinylpyrrolidone (PVP) to prepare the GDY–PVP nanocomposite, which further improved the stability of GDY. By using the GDY–PVP nanocomposite as saturable absorption material, ultrashort pulse lasers with pulse duration of 385.5 ps and 688 fs are obtained at 1 and 1.5 µm, respectively. This work reveals the excellent nonlinear optical properties of GDY and lays a foundation for its development in advanced nanophotonic devices.

metal chalcogenides, [17,18] graphdiyne, [19][20][21] etc.) and perovskites [22][23][24][25][26] have been in a state of vigorous development and rapid advances for applications in optoelectronics, catalysis, energy conversion, due to their autologous admirable chemistry and physics characteristics. [27,28] Porous materials, a scientifically evolving and functionally compelling class of solid compounds with well-defined pore structures, such as metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and polyoxometalates (POMs), have attracted broad research interest because of their wide applications in many fields including, but not limited to, adsorption, separation, catalysis, and photovoltaics. [29][30][31][32] Through fine control over the organic units to create predesigned skeletons, an exceptionally large set of materials with unique porous structures and remarkable properties have been developed. [33,34] MOFs, also known as coordination polymers or coordination networks, are one class of crystalline porous materials prepared by the self-assembly of metal ions or clusters with organic ligands. [35] They have drawn tremendous research interest for their customizable chemical structures along with unique chemical and physical properties, [36][37][38][39][40][41] which guarantee their wide applications as adsorption and separation, catalysts, magnetic, and light emitting materials. [36,[42][43][44][45] The use of appropriate ligands with optimized electronic push-pull structures, the degree of conjugation in the system and the encapsulation of guest molecules with different properties are some of the effective strategies to enhance the linear and nonlinear optical properties of the MOFs materials. [46][47][48] COFs, constructed from organic moltifs linking through strong covalent bonding, are a kind of crystalline porous materials in which the atoms of organic units are precisely integrated to create periodic frameworks and nanopores. [49,50] Although the thermal stability and crystallinity of COFs are lower than MOFs, they have received wide attention due to their low density, large surface area and strong ππ stacking. [51][52][53][54] It has been appreciated that the applications of COFs materials in third-order NLO such as two-photon fluorescence have been well developed in recent years. [55][56][57] Similar to MOFs and COFs, POMs formed by the coordination of early transition metals and oxygen atoms are a class of crystalline porous materials with unique structures and properties for their exceptional crystallinity and high stability. [58] POMs are intrinsically electron deficient, and their electronaccepting capability in combination with highly delocalized π-conjugated systems is particularly promising for producing NLO materials. [59,60] The structure of all the crystalline porous Crystalline porous materials have been extensively explored for wide applications in many fields including nonlinear optics (NLO) for frequency doubling, two-photon absorption/emission, optical limiting effect,...

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fascinating physical and chemical properties. At present, two dimensional (2D) materials with brilliant nonlinear optical (NLO) properties play an key role in modern photonics since the appearance of graphene. [15] However, GDY, as a 2D allotrope of graphene, is still in the primary stage of its application in photonic fields. [16,17] On the basis of previous research results, the advantages of GDY as a NLO material for photonic devices are obvious. First, it is essentially different from the zero-band gap of graphene. GDY has a tunable direct band gap of 0.46-1.10 eV (according to different simulated methods), [18][19][20] which shows that GDY has great potential in the application of photonic devices based on optical switch function. Besides, in the structure of GDY, the alkyne bonds and sub-nanopore, provide a large number of reaction sites for its functionalization. In this context, the optical energy gap of the original GDY can be tuned in a wide range of wavelengths by controlling the type and amount of doped atoms (e.g., boron, nitrogen, phosphorus, and sulfur), [21][22][23] which makes GDY a more compatible NLO material. Recently, we used the method of spatial self-phase modulation to demonstrate the strong broadband Kerr nonlinearity and large nonlinear refractive index (in the order of ≈10 −5 cm 2 W −1 ) of GDY, [24] which indicates that GDY can be widely used in multi-functional photonic devices. Compared with the unstable black phosphorus (BP), the GDY material can remain stable up to 1000 K and its service life at room temperature is extremely long. [25] The excellent stability of GDY prevents it from photooxidation and photo degradation under high strong light irradiation, which is of crucial significance for the development of photonic devices that can be used for a long term. In view of this, the research and development of advanced multifunctional photonics devices (e.g., detector, photonic diode, switcher, sensors, and modulator) based on GDY is not only of great significance to fully understand the optical performance of all-carbon nanomaterials, but also promotes the development of photonic devices based on 2D materials.Ultrafast lasers which can be passively generated using saturable absorption of 2D materials play a pivotal role in various cutting-edge technologies such as micromachining, [26] hyperfine medical surgery, [27] and ultrafast information processing. [28] However, up to now, most of the ultrashort pulse generation Graphdiyne (GDY) is a novel 2D all-carbon nanomaterial, which has an intransic band gap, strong light-matter interaction, and large optical absorption in the infrared region, indicating that it has great potential in the field of mid-infrared ultrafast photonics. Here, a Z-scan method is used to demonstrate the broadband and strong nonlinear optical (NLO) response of GDY, and its performance in the application of mid-infrared ultrafast photonics is explored for the first time. The experimental results demonstrate that its nonlinear parameters are superior to the current...

By breaking the restriction of mirrors, random lasers from a disordered medium have found unique applications spanning from displays to spectroscopy to biomedical treatments to light fidelity. Gain media in two dimensions with distinct physical and chemical properties may lead to the next generation of random lasers. Graphdiyne (GDY), a two-dimensional graphene allotrope with intrigued carbon hybridization, atomic lattice, and optoelectronic properties, has attracted increasing attention recently. Herein, the photoemission characteristics and photocarrier dynamics in GDY are systematically studied, and multicolor random lasers have been unprecedently realized using GDY nanosheets as the gain. Considering the well biocompatibility of GDY, these results may look ahead to a plethora of potential applications in the nanotechnology platform based on GDY.

Graphdiyne (GDY), as a rising star of all-carbon materials, features high degree π-conjugation, uniformly distributed pores, and an intrinsic natural bandgap. These characteristics guarantee large optical refractive index, low saturation...