The development of new water oxidation electrocatalysts that are both stable and efficient, particularly in neutral conditions, holds great promise for overall water splitting. In this study, the electrocatalytic water oxidation performance of a new cobalt-based catalyst, Co (BO ) , with a Kotoite-type crystal structure is investigated under neutral conditions. The catalyst is also hybridized with CNTs to enhance its electrocatalytic properties. A remarkable increase in catalytic current along with a significant shift in the onset overpotential is observed in Co (BO ) @CNT. Additionally, CNT addition also greatly influences the surface concentration of the catalyst: 12.7 nmol cm for Co (BO ) @CNT compared with 3.9 nmol cm for Co (BO ) . Co (BO ) @CNT demands overpotentials of 303 and 487 mV to attain current densities of 1 and 10 mA cm , respectively, at pH 7. Electrochemical and characterization studies performed over varying pH conditions reveal that the catalyst retains its stability over a pH range of 3-14. Multi-reference quantum chemical calculations are performed to study the nature of the active cobalt sites and the effect of boron atoms on the activity of the cobalt ions.

Nanomaterials have received increasing attention due to their controllable physical and chemical properties and their improved performance over their bulk structures during the last years. Carbon nanostructures are one of the most widely searched materials for use in different applications ranging from electronic to biomedical because of their exceptional physical and chemical properties. However, BN nanostructures surpassed the attention of the carbon-based nanostructure because of their enhanced thermal and chemical stabilities in addition to structural similarity with the carbon nanomaterials. Among these nanostructures, one dimensional-BN nanostructures are on the verge of development as new materials to fulfill some necessities for different application areas based on their excellent and unique properties including their tunable surface and bandgap, electronic, optical, mechanical, thermal and chemical stability. Synthesis of high quality boron nitride nanotubes (BNNTs) in large quantities with novel techniques provided greater access, and increased their potential use in nanocomposites, biomedical fields and nanodevices as well as hydrogen uptake applications. In this review, properties and applications of one-dimensional BN (1D) nanotubes, nanofibers and nanorods in hydrogen uptake, biomedical field and nanodevices are discussed in depth. Additionally, research on native and modified forms of BNNTs and also their composites with different materials to further improve electronic, optical, structural, mechanical, chemical and biological properties are also reviewed. BNNTs find many applications in different areas, however, they still need to be further studied for improving the synthesis methods and finding new possible future applications.

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The electrocatalytic water oxidation performance of a new cobalt‐based catalyst, Co3(BO3)2, with a Kotoite‐type crystal structure was investigated at neutral pH. Hybridization of the catalyst with carbon nanotubes (CNTs) improved the electrocatalytic properties significantly. Comprehensive electrochemical studies and multi‐reference quantum chemical calculations were performed to study the nature of active cobalt sites as well as the effect of borate coordination to the activity of cobalt ions. More information can be found in the Full Paper by E. Ülker, Y. Dede, F. Karadas, et al. on page 10372.