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The capacitive energy storage performance of activated carbon can be significantly improved by embedding graphene quantum dots owing to the formation of overall conductive networks.

many irreplaceable advantages of high storage capacity, miniaturization, multi plicity, and integration capability. [6][7][8][9][10][11] Among various microoptics/nano optics devices, metasurface, consisting of planar subwavelength structures, has emerged as a particularly powerful plat form for modulating light parameters such as amplitude, [12,13] phase, [14][15][16] wavelength, [17][18][19][20] polarization, [4,[21][22][23] and hybrid parameters, [24,25] which provides the possibility of potential applications of information encryption, data storage, and optical communication. [26][27][28] Microprint and holography are often used as two separate optical encryption strategies applied in independent meta surface devices, which can be achieved by controlling over plasmonic [29][30][31][32][33][34] or all dielectric [35][36][37][38][39][40] structures at the nanoscale. To strengthen optical information secu rity, other parametric freedoms such as polarization, [41][42][43][44][45] wavelength, [17,[46][47][48][49] and spatial freedom [50][51][52] have been explored to achieve multiplexed microprint or holography encryption devices. Very recently, attempts have been imple mented to combine the microprint and holography in a single device. [53][54][55] However, although the combination of holography and microprints brings about the increase of encrypted dimen sions, crosstalk between different channels remains a thorny problem, and devices will not transmit repeatedly between senders and receivers once fabricated. Fabry-Pérot (FP) cavity resonators with narrow spectral linewidth can effectively sup press crosstalk and can be integrated to act as color filters, [56,57] which provides a potential solution. However, significant chal lenges such as realtime encryption, transmission security, and data compactness still need to be overcome.Here, we propose a novel type of metasurfacebased device that combines color FP cavitybased microprint and helicity multiplexed metahologram. Such devices have the encryption dimensions of microprint, holography as well as helicity at the same time by independently manipulating the amplitude, phase, and polarization of the incident light. A specific algo rithmic framework is developed to combine holography with structural color, and the particle swarm optimization (PSO) algorithm is built to optimize the conversion efficiencies of metasurface elements. Furthermore, enabled by a microprint of editable quick response (QR) code, a realtime encryption Optical encryption with multichannel, high complexity, and artistry characteristics has become one of the most significant approaches for modern information security. Recently emerged metasurface-based optics consisting of planar subwavelength metamaterials has been engineered as an ideal platform for optical encryption because of its capability of manipulating various optical parameters and enhancing information storage capacity. However, limited encrypted channels and insufficient real-time encryption abilities hinder its practical applicatio...

electric vehicles. [1,2] However, the further scaled application of commercial LIBs encounters a "bottleneck": the overall energy density is approaching the ceiling due to the restriction of theoretical specific capacity of insertion-type oxide cathodes (≈250 mAh g −1 ) and graphite anodes (372 mAh −1 ). In order to satisfy the increasing demand for higher energy densities particularly under the extended application such as unmanned aerial vehicles, cargo aircraft, electric vehicles, and the exploration of novel storage system is of great significance. [3] Sulfur is earthabundant, low-cost, and environment friendly. More inspiring, lithium-sulfur batteries (LSBs) based on sulfur cathodes exhibit much higher theoretical specific capacity (1675 mAh g −1 ) through the multielectron redox reaction process, showing great potential for high-performance energy storage devices. [4] Despite the promising prospects, the practical application of LSBs is still impeded by several challenges, such as electrical insulation of sulfur and discharge products (Li 2 S/Li 2 S 2 ), severe shuttle effect of long-chain polysulfides (LiPSs, Li 2 S n , 4 ≤ n ≤ 8), low sulfur utilization, and large volume expansion (≈80%), which are critically fatal for the cycle stability and power density. [5] In the last decades, tremendous Lithium-sulfur batteries (LSBs) are severely impeded by their poor cycling stability and low sulfur utilization due to the inevitable polysulfide shuttle effect and sluggish reaction kinetics. This work reports a Mott-Schottky RGO-PANI/MoS 2 (RPM) heterogeneous layer modified separator for commercialsulfur-based LSBs through the vertical growth of molybdenum sulfide (MoS 2 ) arrays on the polyaniline (PANI) in situ reduced graphene oxide (RGO). Due to the synergistic effects of the "reservoir" constructed by MoS 2 and RGO-PANI, strong absorbability, high conductivity, and electrocatalytic activity, RPM exhibits a successive "trapping-interception-conversion" behavior toward lithium polysulfides. As a result, the LSBs assembled using a commercialsulfur as the cathode and RPM as modified layer exhibit high sulfur utilization (3.8 times higher than that of the unmodified separator at 5 C), excellent rate performance (553 mAh g −1 at 10 C), and outstanding high-rate cycle stability (524 mAh g −1 after 700 cycles at 5 C). Moreover, even at a high sulfur loading of 5.4 mg cm −2 , a favorable areal capacity of 3.8 mAh cm −2 is still maintained after 80 cycles. Theoretical calculations elucidate that such a systematic strategy can effectively suppress the shuttling effect and boost the catalytic conversion of intercepted polysulfides. This work may provide a feasible strategy to promote the practical application of commercial-sulfur-based LSBs.

High‐performance photocatalysts should have highly crystallized nanocrystals (NCs) with small sizes, high separation efficiency of photogenerated electron–hole pairs, fast transport and consumption of photon‐excited electrons from the surface of catalyst, high adsorption of organic pollutant, and suitable band gap for maximally utilizing sunlight energy. However, the design and synthesis of these versatile structures still remain a big challenge. Here, we report a novel strategy for the synthesis of ultrasmall and highly crystallized graphene–ZnFe2O4 photocatalyst through interface engineering by using interconnected graphene network as barrier for spatially confined growth of ZnFe2O4, as transport channels for photon‐excited electron from the surface of catalyst, as well as the electron reservoir for suppressing the recombination of photogenerated electron–hole pairs. As a result, about 20 nm ZnFe2O4 NCs with highly crystallized (311) plane confined in the graphene network exhibit an excellent visible‐light‐driven photocatalytic activity with an ultrafast degradation rate of 1.924 × 10−7 mol g−1 s−1 for methylene blue, much higher than those of previously reported photocatalysts such as spinel‐based photocatalysts (20 times), TiO2‐based photocatalysts (4 times), and other photocatalysts (4 times). Our strategy can be further extended to fabricate other catalysts and electrode materials for supercapacitors and Li‐ion batteries.

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