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Herein, we have developed a facile and effective approach for synthesizing a novel kind of porous nitrogen-doped carbon-coated MnO nanosphere. The porous Mn2O3 nanospheres are initially obtained by the calcination treatment of a coordination self-assembled aggregation precursor (referred to as Mn(OAc)2-C-8). Then, MnO@N-doped carbon composites (MnO@NCs) are obtained by the calcination of the Mn2O3 nanospheres coated with polydopamine (Mn2O3@PDA). The MnO@NCs are evaluated as an anode for lithium ion batteries (LIBs), which exhibit high specific capacity, stable cycling performance (1096.6 mA h g−1 after 100 cycles at 100 mA g−1) and high coulombic efficiency (about 99% over 100 cycles). The unique structure design and synergistic effect not only settle the challenges of low conductivity and poor cycling stability of transition metal oxides but also resolve the imperfection of inferior specific capacity of traditional graphite materials. Importantly, it may provide a commendable conception for developing new-fashioned anode materials to improve the lithium storage capability and electrochemical performance.

In this paper, we report a synthetic route for cobalt sulfides nanoparticles embedded in porous carbon fibers (Co9S8@C) by carbonizing polydopamine (PDA)-coated metal coordination polymers (MCPs) and subsequent sulfidation process. This material serves as an anode for lithium-ion batteries, which exhibits high capacity and good rate capability. At a rate of 0.1C, a high reversible capacity of 1565 mA h g−1 is being obtained. In addition, the battery maintains a stable reversible capacities of 606 mA h g−1 for 300 cycles at 1C. The improvement of lithium-storage performance is mainly attributed to the smart design of carbon-wrapped mesoporous Co9S8 fibers, which not only prevents aggregation and volume change of the Co9S8 particles, but also enables good conductivity, and thus enhances electrochemical stability.

A novel type of transition bimetal–organic frameworks was described as a heterogeneous catalyst for the oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordination assembly of manganese(II) and cobalt(II) with 1,3,5-benzenetricarboxylic acid (H3BTC) for the first time. The metal–organic framework material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N2 sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal–organic framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h. More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.

In this study, we describe a rapid and environmentally friendly synthesis of bare Co3O4 nanocrystals derived from Co(ii) oleate complexes by calcination treatment. When directly used as anode materials for lithium-ion batteries (LIBs), the as-prepared nanocrystals could deliver a high reversible capacity of 980 mA h g(-1) after 250 cycles at a current density of 100 mA g(-1) and excellent cycling performance, which may be beneficial to promote the further development of the next generation of lithium ion batteries. The synthetic route can offer great advantages for the flash preparation of other metal oxide nanocrystals for energy storage application.

A novel kind of Co-based metal–organic frameworks (MOFs) are firstly prepared by coordination assembly of Co(II) and 1,3,5-benzenetricarboxylic acid (H3BTC) through a hydrothermal route (referred to as Co-BTC MOF). Such Co-BTC MOF have a zigzag vermicular-like shape with a length of 126 nm and a width of 55 nm. Co-BTC MOFs without calcination treatment are applied as anode materials for lithium-ion batteries (LIBs) and show superior electrochemical performance, including high lithium storage capacity (1739 mA h g−1 in the first discharge process at a current density of 100 mA g−1), excellent coulombic efficiency (above 99% in the 199th cycle) and cycling performance (>750 mA h g−1 over 200 cycles) in the potential range of 0.01–3.0 V vs. Li/Li+. Such excellent electrochemical performance may be derived from the conjugated carboxylate moiety and the linker structure. More importantly, the facile approach may also be extended to other metal-based MOFs and the intriguing results show that nano-sized MOFs will be regarded as futuristic anode materials for advanced lithium storage.

Herein, we have designed graphene-coated porous cobalt oxide fibers (Co3O4@G) using coordination polymers as precursors through calcination followed by a subsequent self-assembly process. The graphene-coated porous cobalt oxide fiber nanostructures not only provide good conductivity, but also prevent the aggregation and volume change of the Co3O4 nanoparticles during lithium storage processes. When serving as anode materials in the lithium-ion batteries, the obtained Co3O4@G composites, exhibit remarkable electrochemical performances, including high specific capacity (∼1303.9 mA h g−1 at a current density of 0.2 A g−1), excellent cycling stability (1153 mA h g−1 retention after 80 cycles at a current density of 0.2 A g−1) and high rate capability.

Herein, we reported a facile route to fabricate carbon and Au treated TiO 2 mesoporous hollow spheres (MHTiO 2 @C–Au) as high performance anode materials for lithium ion batteries. The high porosity of the hollow spheres, together with the inner carbon supporting and superficial Au coating, enhanced the cycling stability and rate performance of the MHTiO 2 @C–Au electrode significantly. The MHTiO 2 @C–Au composite exhibits a high reversible specific capacity of 186.6 mA h g −1 after 200 cycles at the current density of 1.0C, superior rate performances of around 151.0 mA h g −1 at the current rate of 5.0C. The outstanding electrochemical property is attributed to the overall structural features of the MHTiO 2 @C–Au, which can not only shorten the diffusion path of lithium ions and electrons, but also improve the stability of the hollow structures during the lithium ion insertion and extraction process.

In this paper, coaxial nanocables formed of Ag nanowires with a mesoporous structured TiO2 layer coating (denoted as Ag/TiO2) were successfully fabricated through a facile sol–gel method combined with a hydrothermal treatment process and a short post-annealing procedure. The composite nanostructures show the unique feature of a uniform core–shell structure with highly crystalline nanocrystals, small size (∼6 nm), uniform mesopores (∼9 nm), high surface area (∼93.6 m2 g−1) and highly conductive Ag nanowire which favor the excellent electrochemical performance of the Ag/TiO2 nanocable electrode. The resultant Ag/TiO2 nanocables could deliver a superior lithium storage capability (a stable reversible capacity of ∼160 mA h g−1 after 230 cycles at a current density of 1 C).

A novel type of transition bimetal–organic frameworks was described as a heterogeneous catalyst for the oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordination assembly of manganese(II) and cobalt(II) with 1,3,5-benzenetricarboxylic acid (H3BTC) for the first time. The metal–organic framework material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N2 sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal–organic framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h. More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.

In this work, a one-dimensional Co3O4@TiO2 core-shell electrode material with superior electrochemical performance is fabricated by a convenient and controllable route. The approach involves two main steps: the homogeneous deposition of polydopamine and TiO2 layers in sequence on the cobalt coordination polymer and the thermal decomposition of the polymer matrix. The as-prepared electrode material can achieve excellent electrochemical properties and stability as an anode material for lithium ion batteries, such as a high specific capacity of 1279 mA h g(-1), good cycling stability (around 803 mA h g(-1) at a current density of 200 mA g(-1) after 100 cycles), and stable rate performance (around 520 mA h g(-1) at a current density of 1000 mA g(-1)). This dramatic electrochemical performance is mainly attributed to the excellent structural characteristics, which could improve the electrical conductivity and lithium ion mobility, as well as electrolyte permeability and architectural stability during cycling.