Tailoring the d-band center of N-doped carbon nanotube arrays with Co4N nanoparticles and single-atom Co for a superior hydrogen evolution reaction

Abstract A 3D self-supported integrated electrode, consisting of heteroatomic nitrogen-doped carbon nanotube arrays on cloth with confined ultrafine Co 4 N nanoparticles and a distribution anchored single-atom Co, is fabricated via cobalt-catalyzed growth strategy using dicyandiamide as the nitrogen source layered cobalt hydroxide-nitrate salt precursor. The abundance exposed active sites, namely, nanoparticles, N-doped nanotubes, multiple synergistic effects among these components provide suitable tailoring d -band center for facilitating vectorial electron transfer efficient electrocatalysis. Benefiting from merits its structural features electronic configuration, prepared electrode exhibits robust performance toward hydrogen evolution reaction overpotentials only 78 86 mV at 10 mA cm −2 in acidic basic electrolytes, respectively. Density functional theory calculations X-ray photoelectron spectroscopy valence band measurements reveal that effective by plays crucial role optimizing adsorption free energy to more thermoneutral value