Noble-metal-free electrocatalysts are highly desired for the sustainable H-2 production via water electrolysis. Herein, we report on heterostructured MoC-MoP nanoparticles supported by bacterial cellulose-derived N-doped carbon nanofibers (denoted as MoC-MoP/BCNC NFs) as cost-efficient electrocatalysts for hydrogen evolution reaction (HER). As evidenced, the presence of MoC can prevent MoP from coarsening due to the strong interfacial interactions, resulting in ultrafine nanoparticles evenly integrated with conducting N-doped carbon matrix. More importantly, such heterostructured MoC-MoP delivers tailored electronic configurations toward the optimal binding with intermediate H, accomplishing the promoted HER kinetics. Thereby, the MoC-MoP/BCNC NFs exhibit higher HER activity and faster kinetic metrics in comparison with the single-component counterparts (e.g., MoC/BCNC and MoP/BCNC). They afford low overpotentials of 158 and 137 mV to achieve a current density of similar to 10 mV cm(-2) and small Tafel slopes of 58 and 65 mV dec(-1) in 0.5 M H2SO4 and 1.0 M KOH, respectively. Elucidating efficient electrocatalysis on the MoC-MoP interfaces, this work will open up new opportunities for exploring cost-efficient electrocatalysts in sustainable energy conversion. (C) 2019 Elsevier Ltd. All rights reserved.