Mixed metal oxides as efficient electrocatalysts for water oxidation

Hierarchical Porous Carbon Spheres Loaded CoOX (CoOx/HPCS) for Efficient Oxygen Reduction Reaction in Alkaline Media

“…In addition, the Brunauer‐Emmett‐Teller (BET) specific area of HPCS and CoO x /HPCS behaved large specific surface area of 621 m 2 ⋅ g −1 and 350 m 2 ⋅ g −1 , respectively, benefiting from the porous carbon sphere structures and numerous small CoO x nanoparticles. As revealed in the insets in Figure 2a and 2b, the corresponding pore size of HPCS and CoO x /HPCS were 0∼50 nm and 90∼150 nm, demonstrating the formation of a lot of mesoporous structures and a few macroporous structures in the hierarchical porous carbon spheres based electrocatalyst [34,35] . The results above indicated that the porous carbon sphere support could possess a large surface area together with an abundant hierarchical porous structure including mesoporous and microporous structures, which was beneficial to provide massive accessible active sites and repaid mass transport pathways, thereby reducing the mass transfer resistance of related species during the electrochemical ORR process, and enhancing the electrocatalytic performance [11,36] …”

“…As revealed in the insets in Figure 2a and 2b, the corresponding pore size of HPCS and CoO x /HPCS were 0 ~50 nm and 90 ~150 nm, demonstrating the formation of a lot of mesoporous structures and a few macroporous structures in the hierarchical porous carbon spheres based electrocatalyst. [34,35] The results above indicated that the porous carbon sphere support could possess a large surface area together with an abundant hierarchical porous structure including mesoporous and microporous structures, which was beneficial to provide massive accessible active sites and repaid mass transport pathways, thereby reducing the mass transfer resistance of related species during the electrochemical ORR process, and enhancing the electrocatalytic performance. [11,36] The XRD technology is a basic and important characterization method for testing the crystal structure of metals and metal oxides.…”

Investigating the electrocatalytic reduction of 2,4,6-tri-nitro-toluene (TNT) using density functional theory methods

“…Non-precious iron oxide surfaces are considered as TNT electroreduction catalysts due to their abundance and potential to deviate from scaling relationships defined from monometallics. 73,74 Fig. 8b suggest that pure metal surfaces with strong binding of O* (Fe (110), Co (0001), and Ru (0001)) will be limited by the reduction of OH* to H 2 O (l), suggesting that these surfaces may oxidize and be present in the form of an oxide or hydroxide surface at TNT reduction conditions.…”

Nanostructured Ball-Milled Ni–Co–Mn Oxides from Spent Li-Ion Batteries as Electrocatalysts for Oxygen Evolution Reaction

“…Compared to single metal oxides, mixed metal oxides possess richer redox sites and larger lattice parameter that allow higher ion diffusion for oxygen evolution . Moreover, the presence of multiple cations in mixed metal oxides can lower the activation energy for electron transfer, which increases their electronic conductivity . Among mixed transition metal oxides, NiCo-based oxides are one of the most investigated due to their high OER catalytic activity. − Particularly, Ni provides favorable OH – adsorption sites for the first step of OER .…”