Enhanced pervaporative desulfurization performance of PDMS membranes by incorporating MoSe2 nanosheets vertically oriented on graphene

MoSe 2 nanosheets vertically grown on graphene via hydrothermal synthesis. • Expanded interlayer spacing (0.686 nm) provides additional free volume for transport. • Maximum enrichment factor of 5.24 and flux of 4960 g·m −2 ·h −1 achieved. • Selective thiophene transport via σ-coordination and d–π coupling. • Stable performance over 7 days for industrial gasoline desulfurization. Hybrid membranes were fabricated by embedding vertically aligned molybdenum diselenide arrays on graphene (MoSe 2 ⊥G) into polydimethylsiloxane (PDMS) for thiophene removal from n -octane by pervaporation. The MoSe 2 ⊥G nanocomposite was synthesized through a cetyltrimethylammonium bromide (CTAB)-assisted hydrothermal route, in which ultrathin MoSe 2 nanosheets were grown perpendicular to graphene substrates. The introduction of MoSe 2 ⊥G substantially enhanced the desulfurization performance, which was attributed to the expanded interlayer spacing and abundant active edge sites of MoSe 2 . The former provided additional free volume for mass transport, and the latter enabled the selective facilitated transport of thiophene through σ-coordination bonding and d–π electronic coupling. An optimum enrichment factor of 5.24, corresponding to a permeation flux of 4960 g·m −2 ·h −1 , was obtained upon the incorporation of 0.3 wt% MoSe 2 ⊥G with 1312 ppm thiophene in n -octane at 303 K. Notably, the hybrid membrane maintained stable performance over a 7-day period. This work offers an effective strategy for developing two-dimensional material-based separation membranes for industrial-scale gasoline desulfurization. Download: Download high-res image (214KB) Download: Download full-size image