Supercapacitors, as a type of energy storage system, bridge the power/energy gap between conventional capacitors and batteries due to attractive properties such as high power density, long cycle lifespan, and large temperature range. However, the low energy density of supercapacitors compared to lithium‐ion batteries has hindered their general application. In general, the electrochemical performance of supercapacitors is closely related to the structure of their electrode materials, electrolytes, and device design. The main materials used in electrochemical double‐layer capacitors (EDLCs) are carbon materials with various architectures. This is due to their high surface area, good electric conductivity, and intrinsic stability. In this review, recently reported carbon‐based nanostructured electrode materials with 0D, 1D, 2D, and 3D structures are systematically reviewed. The effect of nanostructuring on the properties of supercapacitors including specific capacitance, rate capability, and cycle stability is explored, the details of which may serve as a guide to electrode design for the next generation of EDLCs.

There is an ever‐increasing demand for energy storage combined with high energy density, long lifespan, and low cost. Design and fabrication of electrode materials with characteristics of scale and fast charge (electrons and ions) access to electrochemically active site are of great importance. The aerosol‐spray synthesis technique has shown considerable promise as an attractive, cost‐effective, and scalable route for material preparation. Particles with complex architectures and chemistry can be produced by simply using an economical, continuous, and rapid process. Here, recent advances of the industrially viable aerosol‐spray‐pyrolysis method are summarized with regard to structure design and processing of electrode materials in the field of energy storage. Beginning with an introduction to the principles, characteristics, and process parameters of aerosol‐spray methods, the focus then moves to recent achievements to date in experimental exploration of fabricating a variety of electrode materials for energy‐storage devices, including lithium‐ion batteries, sodium‐ion batteries, supercapacitors, and lithium–sulfur batteries. Also discussed are the current status, directions, and prospects for future exploration of material synthesis using aerosol‐spray techniques. Aerosol‐spray pyrolysis represents an important breakthrough in multidimensional structure design, and exhibits incredible versatility for material fabrication for high‐performance energy‐storage devices.

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In order to overcome the boundary effect and boundary lock problem existing in classical Hewlett-Packard (HP) TiO 2 non-linear model, the authors propose a novel window function for the fractional-order HP TiO 2 non-linear drift model, in which the fractional calculus is utilised to reflect the memory property of the memristor device. The novel window function is general and they can take the previously reported well-known window functions as its special cases by turning parameter a. Compared with the integer-order model, the order α and a in the fractional-order case is important parameters to flexibly realise the nonlinear dopant drift of memristor model even when a wider amplitude range of the input voltage is applied. Simulation results illustrate that their model is flexible, scalable to guarantee the state variable x(t) and the memristor value M α (x) switched between the low and high levels by choosing suitable parameter α and a. A simple practical application also confirms the efficiency of their model to reveal the non-linear dopant kinetics of the memristor device.

Lithium–sulfur (Li–S) batteries are considered to be one of the most promising energy storage systems owing to their high energy density and low cost. However, their wide application is still limited by the rapid capacity fading. Herein, polydopamine (PDA)‐coated N‐doped hierarchical porous carbon spheres (NPC@PDA) are reported as sulfur hosts for high‐performance Li‐S batteries. The NPC core with abundant and interconnected pores provides fast electron/ion transport pathways and strong trapping ability towards lithium polysulfide intermediates. The PDA shell could further suppress the loss of lithium polysulfide intermediates through polar–polar interactions. Benefiting from the dual function design, the NPC/S@PDA composite cathode exhibits an initial capacity of 1331 mAh g−1 and remains at 720 mAh g−1 after 200 cycles at 0.5 C. At the pouch cell level with a high sulfur mass loading, the NPC/S@PDA composite cathode still exhibits a high capacity of 1062 mAh g−1 at a current density of 0.4 mA cm−2.

In this paper, a countermeasure for wireless networked control systems suffering from jamming attacks is studied by a variable sampling approach. A Stackelberg game framework is utilized to analyze interactions between a smart jammer and a legitimate user. The variable sampling approach is exploited to deal with data packets dropout between a sensor and a controller. Moreover, a resilient variable sampling controller is designed by a delta operator method. Besides, stability conditions are provided for systems with proposed controller. Finally, a numerical simulation is provided to validate the effectiveness of the proposed method.

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In this paper, the exponential stability for a class of delayed competitive neural networks is studied. By applying the inequality technique and non-reduced-order approach, some novel and useful criteria of global exponential stability for the addressed network model are established. Moreover, a numerical example is presented to show the feasibility and effectiveness of the theoretical results.