simplicity, and absence of greenhouse gases. [5-8] However, the practical application of this process is limited by a kinetic bottleneck due to the thermodynamically unfavorable nature of the oxygen evolution reaction (OER; ΔH 0 /G 0 = 237 kJ mol −1) and its sluggish kinetics. [9,10] Transition metal compounds, specifically, those containing Co, Ni, or Fe along with non-metals such as O, N, S, Se, and P, are promising OER catalysts capable of outperforming benchmark IrO 2 and RuO 2 catalysts in alkaline solution. [11-15] Among the different transition metalbased hybrids, those containing Co exhibit the highest OER catalytic activity in alkaline media owing to the favorable adsorption/desorption energies of hydroxyl ions or water molecules. [16-18] Feng et al. recently developed highly efficient Co-based nanomaterials for OER in alkaline media through a facile synthetic route, which outperforms novel metal based catalysts such as RuO 2. [19-21] Hence, much effort has been made to further increase the OER catalytic activity of Co-based hybrids via various strategies such as the incorporation of N dopants to form CoN bonds. [18,21] To be specific, pyridinic N-Co bonding facilitates electron storage and transfer between oxygen-containing adsorbed intermediates (e.g., O*, OH*, OO*, and OOH*) and the active sites, thus boosting the electrocatalytic OER performance of Co-based hybrids. Furthermore, the formation of a well-defined hetero interface between highly conductive carbon materials and catalyst nanoparticles can lead to high stability and high activity for alkaline water oxidation. [9,22] In view of the high affinity of N to transition metals, strong physicochemical contacts between metallic Co species and N (especially pyridinic-N) doped carbon supports can effectively enhance interfacial charge transfer to result in synergetic effects for enhanced oxygen electrochemistry. [16,23] Pyridinic-N is an electron-withdrawing species due to the lone pair electrons involved in the resonance, and thus tends to accept electrons from the next C atoms. This results in a number of advantageous factors for enhancing alkaline OER activity; i) favors the adsorption of OER intermediates such a s OH− or OOH− which are typical rate-determining steps (RDS) for alkaline water oxidation or ii) the electron-deficient carbon Transition metal (TM)-based carbon hybrids have numerous applications in the field of regenerative electrochemical energy. The synergetic effects of high conductivity of carbon supports and abundant catalytic active sites in TMs make these hybrids promising oxygen evolution reaction (OER) electrocatalysts. However, strategies for modulating the catalytic active species in the above hybrids are limited despite being highly sought after. Furthermore, the exact roles of chemical species in the hybrids (e.g., N, C, or TM) mainly responsible for this high OER performance remain unknown. Herein, an innovative approach based on atomic layer deposition is developed to tune the true active species in Co nanoparticle/N-doped...

A nitrogen doped carbon nanotube and cobalt nanoparticle hybrid is prepared by a facile atomic layer deposition process exhibiting excellent oxygen evolution activity, and long‐term durability by utilizing a high number of pyridinic nitrogen sites and better electrical conductivity of carbon supports encapsulating metallic cobalt nanoparticles in article number 2002427 by Kang Min Kim, Jin Kuen Park, Young Kyu Jeong, and co‐workers.