Dispersed MoxW(1-x)S2 catalysts were obtained in situ in the hydrocracking (HCK) of vacuum residue (VR) at 693 K at 9.5 MPa H-2 with the same metal loading of 0.113 mmol with varying Mo:W ratios. The intrinsic activities of the catalysts were compared based on the H-2 consumption rate per the surface site number, i.e. TOFs. The Mo0.75W0.25S2 catalyst showed a superior activity with a high TOFs of 0.6012 s(-1) over those of monometallic sulfides of MoS2 (0.4764 s(-1)) or WS2 (0.2550 s(-1)). Transmission electron microscopy (TEM) analysis identified that the morphology and average particle size of the MoWS2 catalyst maintains even after three times of recycles. Moreover, extended X-ray absorption fine structure (EXAFS) analysis confirmed homogeneous distribution of Mo and W species in the MoWS2 phase. (C) 2020 Elsevier Inc. All rights reserved.