Aqueous Zn–Br batteries (ZBBs) offer promising next‐generation high‐density energy storage for energy storage systems, along with distinctive cost effectiveness particularly in membraneless and flowless (MLFL) form. Unfortunately, they generally suffer from uncontrolled diffusion of corrosive bromine components, which cause serious self‐discharge and capacity fade. An MLFL‐ZBB is presented that fundamentally tackles the problem of bromine crossover by converting bromine to the polybromide anion using protonated pyridinic nitrogen doped microporous carbon decorated on graphite felt (NGF). The NGF electrodes efficiently capture bromine and polybromide anions at the abundant protonated nitrogen dopant sites within micropores and facilitate effective conversion of bromine into polybromides through electrochemical–chemical growth mechanism. The MLFL‐ZBBs with NGF exhibit an extraordinary stability over 1000 charge/discharge cycles, with an energy efficiency over 80%, the highest value ever reported among membraneless Zn–Br batteries. Judicious engineering of an atomistically designed nanostructured electrode offers a novel design platform for low cost, high voltage, long‐life cycle aqueous hybrid Zn–Br batteries.

Desiccant driven dehumidification for maintaining the proper humidity levels and atmospheric water capture with minimum energy penalty are important aspects in heat pumps, refrigeration, gas and liquid purifications, gas sensing, and clean water production for improved human health and comfort. Water adsorption by using nanoporous materials has emerged as av iable alternative to energy-intensive industrial processes,t hus understanding the significance of their porosity,h igh surface areas, vast pore volumes, chemical and structural features relative to the water adsorption is quite important. In this review article, important features of nanoporousm aterials are presented, including zeolites, porouscarbons, as well as crystalline and amorphous porous organicp olymers (POPs) to define the interactions between the water molecules and the polar/non-polar functional groups on the surface of thesen anoporous materials. In particular,f ocus is placed on the recent developments in POPs in the contexto fw ater capture as ar esult of their remarkable stability towards water and wider ange of availables ynthetic routes and buildingb locks for their synthesis. We also highlighted recenta pproaches to increase the water sorption capacity of POPs by modifyingt heir structure, morphology,p orosity,a nd chemical functionality while emphasizing their promisingf uture in this emerging area.

The synthesis of highly microporous, epoxy-functionalized porous organic polymers (ep-POPs) by a one-pot, catalyst-free Diels-Alder cycloaddition polymerization is reported. The high oxygen content of ep-POPs offer efficient hydrogen-bonding sites for water molecules, thus leading to high water-uptake capacities up to 39.2-42.4 wt % under a wide temperature range of 5-45 °C, which covers the span of climatic conditions and manufacturing applications in which such materials might be used. Importantly, ep-POPs demonstrated regeneration temperatures as low as 55 °C, as well as excellent water stability, recyclability, and high specific surface areas up to 852 m g .

We present a new polymerization strategy, that is catalyst-free Diels-Alder cycloaddition polymerization and subsequent FeCl 3 -catalyzed intramolecular cyclodehydrogenation reaction, to introduce graphene nanoribbons up to 2 nm in length and 1.1 nm in width into a graphene nanoribbon framework (GNF). The first graphene nanoribbon framework showed high thermal stability up to 400 o C in air with relatively narrow pore size distribution and exhibited BET surface area of 679 m 2 g -1 . GNF possesses high affinity for H 2 (Q st 7.7 kJ mol -1 , 1.03 wt% at 77 K, 1 bar), CO 2 (Q st = 28.7 kJ mol -1 , 94.6 mg g -1 at 273 K, 1 bar), and CH 4 (Q st = 24. 1 kJ mol -1 , 11.5 mg g -1 at 273 K, 1 bar). The enhancement in gas affinities was attributed to the unique combination of large π-surface area arising from graphene nanoribbons and small pores (~5.8 Å) in GNF. The application of GNF can also be extended to natural gas purification process with exceptional CO 2 /CH 4 (5:95) selectivity of 62.7, which is being the highest value reported to date at 298 K. Unlike previous studies which focus mostly on increasing the affinity of CO 2 towards the sorbent in order to tune CO 2 /CH 4 selectivity, our approach takes advantage of the kinetic diameter difference between CO 2 (3.30 Å) and CH 4 (3.80 Å), thus offering low-cost efficient alternative for natural gas purification process.

Dimensionality plays an important role in the charge transport properties of organic semiconductors. Although three‐dimensional semiconductors, such as Si, are common in inorganic materials, imparting electrical conductivity to covalent three‐dimensional organic polymers is challenging. Now, the synthesis of a three‐dimensional π‐conjugated porous organic polymer (3D p‐POP) using catalyst‐free Diels–Alder cycloaddition polymerization followed by acid‐promoted aromatization is presented. With a surface area of 801 m2 g−1, full conjugation throughout the carbon backbone, and an electrical conductivity of 6(2)×10−4 S cm−1 upon treatment with I2 vapor, the 3D p‐POP is the first member of a new class of permanently porous 3D organic semiconductors.

A novel kinematic structure for a parallel manipulator with 6 DOF is proposed. It consists of a platform that is connected to a fixed base by means of 3-PPSP (P—prismatic joint, Sspherical joint) subchains. Each subchain is connected to a passive prismatic joint at the one end, and a passive spherical joint at the other. The spherical joint is then attached to perpendicularly arranged prismatic actuators that are fixed to the base. Due to the efficient architecture, the closed-fonn solutions of the inverse and forward kinematics can be easily obtained.As a consequence, this new kinematic structure can be servo controlled using simple inverse kinematics, because forward kinematics allows for measuring the platform 's position and orientation in Cartesian space. Manipulator workspace determination is carried out through the computation of displacements in the prismatic joints. A Jacobian matrix for the proposed structure is derived so the relationship between actuator forces and output forces/moments of the mechanism can be analyzed. A series of simulations were performed to verify the results of the kinematics analyses and to evaluate the load characteristics of the system.

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Closed-form forward/reverse position solutions for a 6-degree-offreedom (DoF) parallel mechanism that has some type of nonsymmetric geometry are derived in this study. Particularly, the derived forward-position analysis is applicable to the mechanisms in which three passive joints are constrained to move parallel to the moving plate. Its kinematic and dynamic characteristics are investigated via isotropic index of the Jacobian matrix and isotropic index of the output effective inertia matrix, respectively. From this investigation, it is found that the mechanism has fairly uniform kinematic/dynamic characteristics throughout its workspace. To examine the effectiveness of the proposed 3-PPSP-type mechanism, a prototype is designed, implemented, and tested experimentally under various operating conditions. A simple PID controller is applied to the system, and its joint positions are servo-controlled. The controlled system showed a good trajectory performance. Noting that a more advanced controller requiring a forward-and/or reverse-position solution can be applied to the system in real time, it can be contended that the manipulator is a candidate for the high-precision manipulator.