Rolltronics-enabled MoS₂ nanoscroll for efficient hydrogen evolution

Rolltronics represents an emerging curvature engineering paradigm utilizing van der Waals nanoscrolls to tailor material properties beyond planar twistronic systems. Rolltronics modulation holds great promise as a new platform to advance the hydrogen evolution reaction (HER) activity of MoS₂. Here, we designed 1T-MoS₂ nanoscrolls via asymmetric stress induced by the different defect densities on opposite surfaces of MoS₂ sheets to serve as highly efficient HER catalyst. In the dye-sensitized photocatalytic system with Eosin Y (EY) serving as the photosensitizer ,and triethanolamine (TEOA) acts as the sacrificial electron donor to regenerate EY and sustain the photocatalytic cycle, the 1T-MoS₂ nanoscrolls exhibited extraordinary HER activity with 24.1 mmol g⁻¹ h⁻¹ under UV-visible light, which is nearly 25 times higher than that of the semiconducting pristine 2H-MoS₂ nanosheets. This superior activity originates from the synergistic effects of abundant active sites exposed by S-vacancies, enhanced charge transfer from the metallic 1T phase, and optimized hydrogen adsorption free energy (ΔG_H*). The improved HER activity of 1T-MoS₂ nanoscrolls can be mainly attributed to the metallic conductive characteristic of the 1T phase, abundant S-vacancy-derived active sites, curvature-modulated hydrogen adsorption energy, as well as facilitated mass transfer within the tubular architecture. This rolltronics engineering strategy provides a viable pathway for designing low-cost and highly efficient transition metal dichalcogenide for large-scale energy applications.