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HIGHLIGHTS • A novel coordination polymerization-driven hierarchical assembly approach for spatially controlled fabrication of phytic acid-based bio-derivatives was developed. • The resultant ferric phytate bio-derived polymer featured hollow nanosphere architecture, ordered meso-channels, high surface area, and large pore volume, as anode material, delivering a remarkable electrochemical performance.

Nowadays, new approaches to fabricate high-performance electrode materials are of vital importance in the renewable energy field. Here, we present a facile synthesis procedure of 3D Ni(OH)/graphene hybrids for supercapacitors via synchronous electrochemical-assisted exfoliation and assembly of graphene on 3D Ni(OH) networks. With the assistance of an electric field, the electrochemically exfoliated high-quality graphene can be readily, uniformly assembled on the surfaces of 3D Ni(OH). When serving as electrode materials for supercapacitors, the resulting 3D Ni(OH)/graphene composites exhibited excellent specific capacitance (263 mF cm at 2 mA cm), remarkable rate capability and super-long cycle life (retention of 94.1% even after 10 000 continuous charge-discharge cycles), which may be attributed to their highly porous, stable 3D architecture as well as uniform, firm anchoring of ultrathin graphene on their surfaces. Therefore, our approach provides a facile strategy for the large-scale synthesis of high-quality graphene based composites towards various applications.

A rationally designed strategy is developed to synthesize hierarchically porous Fe-based metal-organic frameworks (P-Fe-MOF) via solution-based self-assembly of diblock copolymers. The well-chosen amphiphilic diblock copolymers (BCP) of polystyrene-block-poly(acrylic acid) (PS-b-PAA) exhibits outstanding tolerance capability of rigorous conditions (e.g. strong acidity or basicity, high temperature and pressure), steering the peripheral crystallization of Fe-based MOF by anchoring ferric ions with outer PAA block. Importantly, the introduction of BCP endows MOF materials with additional mesopores (∼40 nm) penetrating whole crystals, along with their inherent micropores and introduced macropores. The unique hierarchically porous architecture contributes to fast charge transport and electrolyte ion diffusion, and thus promotes their redox reaction kinetics processes. Accordingly, the resultant P-Fe-MOF material as a new electrode material for supercapacitors delivers the unprecedented highest specific capacitance up to 78.3 mAh g−1 at a current density of 1 A g−1, which is 9.8 times than that of Fe-based MOF/carbon nanotubes composite electrode reported previously. This study may inspire new design of porous metal coordination polymers and advanced electrode materials for energy storage and conversion field.

Transition metal hydroxides and graphene composite holds great promise to be the next generation of high performance electrode material for energy storage applications. Here we fabricate the cypress leaf-like Cu(OH) 2 nanostructure/graphene nanosheets composite through one-step in situ synthesis process, employed as a new type of electrode material for high efficiency electrochemical energy storage in supercapacitors. A solution-based two-electrode system is applied to synthesize Cu(OH) 2 /graphene hybrid nanostructure, where anodic graphene nanosheets firmly anchor cathodic Cu(OH) 2 nanostructure due to the electrostatic interaction. The in situ self-assembly of Cu(OH) 2 /graphene ensures good structural robustness and the cypress leaf-like Cu(OH) 2 nanostructure prompt to form the open and porous morphology. The hybrid structure would facilitate charge transport and effectively mitigate the volume changes during long-term charging/discharging cycles. As a consequence, the Cu(OH) 2 /graphene composite exhibits the highest capacitance of 317 mF/cm 2 at the current density of 1 mA/cm 2 and superior cyclic stability with no capacitance decay over 20,000 cycles and remarkable rate capability at increased current densities.

Surface sulfation significantly boosts the supercapacitive performance of ultrathin mesoporous NiCo2O4 nanosheet arrays through enhancing surface reactivity.

The precise regulation of nucleation growth and assembly of polymers is still an intriguing goal but an enormous challenge. In this study, we proposed a pre‐polymerization strategy to regulate the assembly and growth of polymers by facilely controlling the concentration of polymerization initiator, and thus obtained two kinds of different nanosheet‐based porphyrin polymer materials using tetrakis‐5,10,15,20‐(4‐aminophenyl) porphyrin (TAPP) as the precursor. Notably, due to the π–π stacking and doping of TAPP during the preparation process, the obtained PTAPP‐nanocube material exhibits a high intrinsic bulk conductivity reaching 1.49×10−4 S m−1. Profiting from the large π‐conjugated structure of porphyrin units, closely stacked layer structure and excellent conductivity, the resultant porphyrin polymers, as electrode materials for lithium ion batteries, deliver high specific capacity (≈650 mAh g−1 at the current density of 100 mA g−1), excellent rate performance and long‐cycle stability, which are among the best reports of porphyrin polymer‐based electrode materials for lithium‐ion batteries, to the best of our knowledge. Therefore, such a pre‐polymerization approach would provide a new insight for the controllable synthesis of polymers towards custom‐made architecture and function.

High-performance supercapacitors are very desirable for many portable electronic devices, electric vehicles and high-power electronic devices. Herein, a facile and binder-free synthesis method, galvanic displacement of the precursor followed by heat treatment, is used to fabricate ultrathin CoO nanosheet arrays on nickel foam substrate. When used as a supercapacitor electrode the prepared CoO on nickel foam exhibits a maximum specific capacitance of 1095 F g at a current density of 1 A g and good cycling stability of 71% retention after 2000 cycling tests. This excellent electrochemical performance can be ascribed to the high specific surface area of each CoO nanosheet that comprises numerous nanoparticles.