Synthesis of morphology controllable porous Co₃O₄ nanostructures with tunable textural properties and their catalytic application

Abstract

Porous cobalt oxide (Co3O4) nanorod (50-100 nm) and nanosheet-like (70-100 nm) particles were synthesized by a facile hydrothermal method at 150 °C for 2-5 h and 12-24 h, respectively, using aqueous-based precursors like cobalt nitrate, urea and water in the absence of any templating agents followed by their calcination at 300 °C. Morphology and textural properties were tuned by changing the synthesis time at 150 °C. A 3D architecture of Co3O4 was formed by the self-assembly of nanostructured (nanorod and nanosheet) particles. The BET surface area, pore volume and pore diameter of the sample prepared at 150 °C for 5 h were 112 m(2) g(-1), 0.5 cm(3) g(-1) and 7.4 nm, respectively, and it exhibited the highest catalytic performance with a rate constant of 56.8 × 10(-3) min(-1) for the degradation of Chicago Sky Blue 6B, a carcinogenic azo dye used in the textile, paper and food industries. Rod-like particles with a mesoporous structure rendered a better catalytic efficiency than sheet-like particles having both microporous and mesoporous structures. An interrelationship amongst the morphology, textural properties and the catalytic efficiency of Co3O4 was established.

Morphology-controlled fabrication of Co3O4 nanostructures and their comparative catalytic activity for oxygen evolution reaction

“…In the present work, this porous structure is stable and condensed, attributing to the rapidity and uniform heating process. The result is different from the previous report of Roy et al [9], in which the pores became discontinued or blocked after long-time hydrothermal treatment. The corresponding SAED is shown in the inset of Fig.…”

“…Ibupoto et al [20] prepared Co 3 O 4 nanoflowers and nanowires by tailoring the concentration of urea, and the nanoflowers presented selectively sensitive to glucose. Therefore, it is an effective way to employ adjusting the concentration of urea instead of costing long reaction time for synthesizing Co 3 O 4 nanostructures, which could avoid the micro-/nanostructures and open spaces between neighboring particles being destroyed or blocked [9]. Hence, controlling of urea concentration in rapid and easily microwave-hydrothermal should be a facile and low-cost way for fabricating Co 3 O 4 with desirable micro-/nanostructures.…”

“…Thus, it has attracted much attention to fabricate Co 3 O 4 with various morphology and structures, for expecting the higher activity in electrochemical applications. Recently, Co 3 O 4 nanocubes [8], nanorods [9], nanobelts [10] and nanospheres [11] have been synthesized by sol-gel [12], chemical vapor deposition [13], template method [14] and hydro/ solvothermal [15]. However, these reported preparation methods for Co 3 O 4 nanostructures have some shortcomings, such as toxicity of solvents, expensive catalysts and time-consuming process.…”

Controllable 1D and 2D Cobalt Oxide and Cobalt Selenide Nanostructures as Highly Efficient Electrocatalysts for the Oxygen Evolution Reaction

“…To overcome this kind of defect, Roy et al. synthesized congenetic Co 3 O 4 nanorod‐ and nanosheet‐like particles by using the same synthetic process at different hydrothermal reaction times, and then comparing the catalytic efficiency . Rodlike particles rendered a better catalytic activity than that of sheetlike particles for the degradation of Chicago Sky Blue 6B (CSB) in the presence of H 2 O 2 .…”

Synthesis and catalytic property of facet-controlled Co3O4structures enclosed by (111) and (113) facets

“…5 Furthermore, hexagonal β-NiIJOH) 2 nanoplates with exposed (001) and (100) planes could be prepared via a microwave-assisted hydrothermal approach, and where the (100) planes showed more favorable electrochemical activity than the (001) planes. [13][14][15][16][17][18] It is noteworthy that Co 3 O 4 nanomaterials with different crystal planes exposed exhibit greatly different properties. [7][8][9][10][11][12] So far, Co 3 O 4 with different morphologies have been reported, such as nanocubes, nanoboxes, flower-like structures, nanorods, and porous structures.…”