Due to various compositions and morphologies, exquisite intrinsic architectures, and renewability, biomass has been used to generate carbon electrodes for supercapacitors.

Graphene‐based nanocomposites are characterized by high mechanical strength, excellent electrical conductivity, and outstanding thermal and chemical stability. Additionally, the combination of versatile functionalization chemistry and simplicity of large‐scale synthesis makes graphene ideal for electrode materials for energy storage devices. To improve the electrochemical performance even further, recent research has focused on the preparation of porous graphene structures, either by creating holes in the graphene sheets or by assembling them into a 3D porous framework. Porous graphene and reduced graphene oxide allow for rapid ion diffusion and display high real surface area. In this review paper, the conventional methods for the preparation of porous graphene are summarized and recent progress in porous graphene‐based nanomaterials for electrochemical energy storage devices is discussed.

Printed electronics is a rapidly expanding research field because of its incomparable economic efficiency. While various types of inks are employed in the printing of electronics, metal–organic decomposition (MOD) ink is an interesting type of ink worth paying attention to. MOD ink consists of metals in their ionic state and the advantages include simple preparation, long shelf life, high jetting stability, and low temperature processing. Additionally, the ease of large‐scale fabrication through industrial scale printing processes makes MOD ink ideal for printed electronics. To improve the conductivity, morphology, and variety of the conductive substance resulting from MOD ink, recent research has focused on the variation of the ink composition, printing techniques, and sintering methods. Here, the conventional methods of preparation and processing of MOD ink are introduced, followed by discussion of various research efforts to date. Furthermore, applications and their examples including but not limited to conventional conductive patterning are presented.

HIGHLIGHTS • CNT/MnO 2 /graphene-grafted carbon cloth electrode is designed and achieves high MnO 2 mass loading (9.1 mg cm −2). • The electrode with favorable electronic/ionic conductivity delivers a large areal capacitance and rate capability. • The assembled asymmetric supercapacitor yields a large energy density of 10.18 mWh cm −3 .

It is still a challenging task to develop a facile and scalable process to synthesize porous hybrid materials with high electrochemical performance. Herein, a scalable strategy is developed for the synthesis of few-layer MoS2 incorporated into hierarchical porous carbon (MHPC) nanosheet composites as anode materials for both Li- (LIB) and Na-ion battery (SIB). An inexpensive oleylamine (OA) is introduced to not only serve as a hinder the stacking of MoS2 nanosheets but also to provide a conductive carbon, allowing large scale production. In addition, a SiO2 template is adopted to direct the growth of both carbon and MoS2 nanosheets, resulting in the formation of hierarchical porous structures with interconnected networks. Due to these unique features, the as-obtained MHPC shows substantial reversible capacity and very long cycling performance when used as an anode material for LIBs and SIBs, even at high current density. Indeed, this material delivers reversible capacities of 732 and 280 mA h g(-1) after 300 cycles at 1 A g(-1) in LIBs and SIBs, respectively. The results suggest that these MHPC composites also have tremendous potential for applications in other fields.

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Here, a novel fabrication technique for integrated organic devices on substrates with complex structure is presented. For this work, free-standing polymeric masks with stencil-patterns are fabricated using an ultra-violet (UV) curable polyurethaneacrylate (PUA) mixture, and used as shadow masks for thermal evaporation. High fl exibility and adhesive properties of the freestanding PUA masks ensure conformal contact with various materials such as glass, silicon (Si), and polymer, and thus can also be utilized as patterning masks for solution-based deposition methods, such as spin-coating and dropcasting. Based on this technique, a number of integrated organic transistors are fabricated simultaneously on a cylindrical glass bottle with high curvature, as well as on a fl at silicon wafer. It is anticipated that these results will be applied to the development of various integrated organic devices on complexstructured substrates, which can lead to further applications.

Recently, transition-metal phosphides and phosphates have been recognized as candidates for electrochemical energy storage and conversion application. However, the preparation of such materials usually requires high energy consumption and toxic precursors which are considered to be drawbacks for real applications. In this study, we report ambient temperature synthesis of transition-metal phosphates for oxygen evolution reaction (OER) and supercapacitors. The prepared iron-doped porous nickel pyrophosphate (NFPy) nanoparticle is synthesized via simple stirring in ambient temperature using only the precursor for Ni, Fe, and pyrophosphate without any heat treatment. The usage of pyrophosphate promotes facile Ni oxidation and high chemical stability, which overall is beneficial for electrochemical applications and the environment. The OER performance of NFPy shows promising results which required an overpotential of 0.210 V to reach 10 mA·cm–2. Also, with the help of carbon nanotubes, the supercapacitor using NFPy exhibits a good electrochemical performance with a capacity of 517 C·g–1 at 1 A·g–1. The prepared NFPy possesses excellent long-term chemical stability that maintained its chemical valence state and electrochemical performance for over 8 months despite the exposure of air.