Three-dimensional (3D) graphene-based composite materials have attracted increasing attention, owing to their specific surface area, high conductivity and electronic interactions. Here, we report a convenient route to fabricate a 3D Co3O4/Graphene Hydrogel (CGH) composite as an electrode material for supercapacitors. Utilizing the gelation of a graphene oxide dispersion enables the anchoring of...

Transition metal oxides have been suggested as innovative, high-energy electrode materials for lithium-ion batteries because their electrochemical conversion reactions can transfer two to six electrons. However, nano-sized transition metal oxides, especially Co3O4, exhibit drastic capacity decay during discharge/charge cycling, which hinders their practical use in lithium-ion batteries. Herein,...

The functionality or oxidation state of cobalt within a silica matrix can be tailored through the use of cationic surfactants and their halide counter ions during the sol-gel synthesis. Simply by adding surfactant we could significantly increase the amount of cobalt existing as Co3O4 within the silica from 44% to 77%, without varying the cobalt precursor concentration. However, once the surfact...

in this paper, an energetic coordination compound namely pentamminenitratocobalt(iii) nitrate, [co(nh3)5(no3)](no3)2, was used as a new precursor for the preparation of co3o4 nanoparticles. the results showed that the complex is easily decomposed into the co3o4 nanoparticles at low temperature (200 °c) without employing a surfactant or solvent and any complicated equipment. the product was char...

α-MnO2 nanotubes-supported Co3O4 (Co3O4/MnO2) and its carbon nanotubes (CNTs)-hybrids (Co3O4/MnO2-CNTs) have been successfully developed through a facile two-pot precipitation reaction and hydrothermal process, which exhibit the superior bi-functional catalytic activity for both ORR and OER. The high performance is believed to be induced by the hybrid effect among MnO2 nanotubes, hollow Co3O4 a...

Large Li2O2 aggregations can produce high-capacity of lithium oxygen (Li-O2) batteries, but the larger ones usually lead to less-efficient contact between Li2O2 and electrode materials. Herein, a hierarchical cathode architecture based on different discharge characteristics of α-MnO2 and Co3O4 is constructed, which can enable the embedded growth of large Li2O2 aggregations to solve this problem...

In the present work, a novel photocatalytic fuel cell (PFC) system involving a dual heterojunction photoelectrodes, viz. polyaniline/TiO2 nanotubes (PANI/TiO2 NTs) photoanode and CuO/Co3O4 nanorods (CuO/Co3O4 NRs) photocathode, has been designed. Compared to TiO2 NTs electrode of PFC, the present heterojunction design not only enhances the visible light absorption but also offers the higher eff...

The preferential oxidation of carbon monoxide has been identified as an effective route to remove trace amounts of CO (approx. 0.5-1.0 vol%) in the H2-rich reformate gas stream after the low-temperature water-gas shift. Instead of noble metal-based catalysts, Co3O4-based catalysts were investigated in this study as cheaper and more readily available alternatives. This study aimed at investigati...

In this paper, macrocyclic cobalt(II) complexes [CoL1](NO3)2.4H2O (1) and [CoL2](NO3)2.2H2O (2) have been synthesized from the reaction of dialdehydes 1,2-bis(2-formylphenyl)ethane and 1,3-bis(2-formylphenyl)propane, Co(NO3)2.6H2O and 1,2-cyclohexanediamine with molar ration 1:1:1 in methanole and characterized by elemental analyses and FT-IR spectroscopy. Then used as precursors for preparatio...

In this paper, macrocyclic cobalt(II) complexes [CoL1](NO3)2.4H2O (1) and [CoL2](NO3)2.2H2O (2) have been synthesized from the reaction of dialdehydes 1,2-bis(2-formylphenyl)ethane and 1,3-bis(2-formylphenyl)propane, Co(NO3)2.6H2O and 1,2-cyclohexanediamine with molar ration 1:1:1 in methanole and characterized by elemental analyses and FT-IR spectroscopy. Then used as precursors for preparatio...