Searching for inexpensive, efficient and durable electrocatalysts with earth-abundant elements toward the hydrogen evolution reaction (HER) is of vital importance for the future sustainable hydrogen economy, yet still remains a formidable challenge. Herein, a facile template-engaged strategy is demonstrated for the direct in-situ growth of Ni nanoparticles and N-doped carbon nanotubes on carbon nanorod substrates, forming a hierarchically branched architecture (abbreviated as Ni@N-C NT/NRs hereafter). The elaborate construction of such unique hierarchical structure with tightly encapsulated Ni nanoparticles and open configuration endows the as-fabricated Ni@N-C NT/NRs with abundant well-dispersed active sites, enlarged surface area, reduced resistances of charge transfer and mass diffusion, and reinforced mechanical robustness. As a consequence, the optimal Ni@N-C NT/NR catalyst demonstrates superior electrocatalytic activity with relatively low overpotential of 134 mV to deliver a current density of 10 mA·cm^-2 and excellent stability for HER in 0.1 M KOH, holding a great promise for practical scalable H₂ production. More importantly, this work offers a reliable methodology for feasible fabrication of robust high-performance carbon-based hierarchical architectures for a variety of electrochemical applications.

To address the insufficient electrocatalytic activity and stability of formic acid oxidation reaction (FAOR) electrocatalysts, as well as their high cost, we herein demonstrate the facile hydrothermal synthesis of ultrathin AgPt alloy nanowires using amine-terminated poly(N-isopropylacrylamide) (PNIPAM-NH₂) as a structure-directing agent. The initial generation of AgCl precipitates, subsequent formation of AgPt nanoparticles, and their oriented attachment account for the formation of ultrathin AgPt alloy nanowires. Benefiting from their unique 1D anisotropy and alloyed composition, the prepared ultrathin AgPt nanowires exhibit a superior electrocatalytic activity and better CO tolerance for the FAOR, reaching a 1.6-fold and 3.7-fold higher specific current density than AgPt nanoparticles and a commercial Pt black catalyst, respectively. Additionally, the ultrathin AgPt alloy nanowires manifest a superior electrochemical stability and structural robustness during electrocatalysis, making them a promising FAOR electrocatalyst. This work not only provides a reliable strategy for the synthesis of noble metal-based ultrathin nanowires, but also opens an avenue towards the rational design of efficient electrocatalysts for fuel cell systems.