GO ‐Loading‐Dependent Interfacial Architecture and Photocatalytic Behavior of MoSe 2 /Graphene Oxide Hybrid Materials

MoSe 2 /graphene oxide (MoSe 2 /GO) hybrids with controlled GO loadings were prepared through an ex‐situ hydrothermal route using commercial MoSe 2 and GO as starting materials. The approach provides a relatively simple synthesis sequence while maintaining the crystalline 2H‐MoSe 2 phase. XRD, SEM/EDS, TEM, N 2 physisorption, and XPS analyses indicated that GO incorporation improved MoSe 2 dispersion, increased accessible surface area, and promoted close MoSe 2 –GO interfacial contact. Diffuse reflectance spectroscopy showed only minor changes in the apparent optical band gap after GO addition, whereas transient photocurrent and electrochemical impedance measurements suggested more favorable charge separation and interfacial charge transfer in the hybrid materials. Among the compositions examined, MoSe 2 /GO‐10 wt% showed the most balanced photocatalytic response, giving an apparent crystal violet degradation rate constant of 0.0402 h −1 . Under CO 2 ‐saturated alkaline conditions and UV irradiation, this sample also showed improved hydrocarbon formation relative to pristine MoSe 2 , with a maximum CH 4 formation rate of 0.3735 μmol g −1 h −1 and an apparent CO 2 consumption rate of 0.5342 μmol g −1 h −1 . Scavenger experiments and EPR analysis indicated that •O 2 − and •OH were the main reactive species involved in dye degradation. The results suggest that the photocatalytic behavior of MoSe 2 /GO hybrids is governed by a balance among GO‐assisted charge extraction, textural modulation, light utilization, and accessible MoSe 2 surface sites. This work provides a composition‐dependent structure–property perspective for designing carbon‐supported transition‐metal dichalcogenide hybrid photocatalysts, while further isotope‐labeling and carbon‐balance studies are needed to verify detailed CO 2 ‐reduction pathways.