The major challenges related to non-noble-metal electrocatalysts toward the hydrogen evolution reaction (HER) in an acidic environment are to overcome their low efficiency and poor stability. For this purpose, we propose a rational top-down method to construct a hybrid structure of nickel encased by a carbon shell (Ni@C) using CH4 as a carbon source and Ni wire as a sacrificing template during an electrical explosion of wire. The Ni@C nanoparticles are introduced as highly active and durable non-noble metal electrocatalysts for the HER. The optimized Ni@C (15%) core-shell catalyst (CH4/Ar = 15/85 pressure ratio) demonstrates the highest catalytic activity for the HER with an overpotential of 85 mV to drive a current density of -10 mA cm−2 and displays a low Tafel slope of 44 mV dec−1. Another virtue of Ni@C (15%) is its superior stability during an unattenuated HER chronoamperometry for over 24 h. Furthermore, it endures over 168 h submerging in 2 M H2SO4 solution without losing its catalytic activity for HER.