Nanoarchitectonics of few-layer Ni3Fe nanosheets embedded porous nitrogen-doped carbon derived from asphalt waste: An efficient electrocatalyst for oxygen evolution reaction

The design and fabrication of stable, high-performance, and affordable oxygen evolution reaction (OER) electrocatalysts is essential for performing practical water electrolysis and generating green hydrogen energy. Here, we report that 2D few layer Ni3Fe nanosheets embedded with 2D porous nitrogen doped carbon (N-NixFe@CF) from asphalt waste and then convolved and assembled into 1D hollow nanotube structures by Lewis acid molten salt etching method, which were used as electrocatalysts for OER. Benefiting from the integrate of 1D hollow nanotube structure and 2D porous nanosheets, the close contact between catalysts and support, and the increased conductivity, the resultant N-Ni3Fe@CF catalysts exhibited high catalytic activities in the OER with low overpotential at a current density of 10 mA cm−2 (114 mV), low Tafel slope (166.6 mV dec−1), and excellent electrochemical stability. This work provides a new concept for expanding the use of asphalt wastes and by-products, as well as a straightforward synthesis method for producing economical, efficient, and long-lasting alkaline OER electrocatalysts. •A 1D hollow nanotube shape N-NixFe@CF was prepared by Lewis acid molten salt etching method.•The N-NixFe@CF exhibits excellent electrocatalytic activity for oxygen evolution reaction.•It outperforms commercial noble metal-based catalyst of RuO2 and most catalysts reported so far.•The outstanding OER activity is ascribed to the novel synthetic process and porous structure.