Surface functionalized highly porous date seed derived activated carbon and MoS2 nanocomposites for hydrogenation of CO2 into formic acid.

Abstract In recent years, substantial progress has been made towards developing effective catalysts for the hydrogenation of CO2 into fuels. However, the quest for a robust catalyst with high activity and stability still remains challenging. In this study, we present a cost-effective catalyst composed of MoS2 nanosheets and functionalized porous date seed-derived activated carbon (f-DSAC) for hydrogenation of CO2 into formic acid (FA). As-fabricated MoS2/f-DSAC catalysts were characterized by FE-SEM, XRD, Raman, FT-IR, BET, and CO2-TPD analyses. At first, bicarbonate (HCO3–) was successfully converted into FA with a high yield of 88% at 200 °C for 180 min under 10 bar H2 atmosphere. A possible reaction pathway for the conversion of HCO3– into FA is postulated. The catalyst has demonstrated high activity and long-term stability over five consecutive cycles. Additionally, MoS2/f-DSAC catalyst was effectively used for the conversion of gaseous CO2 into FA at 200 °C under 20 bar (CO2/H2 = 1:1) over 15 h. The catalyst exhibited a remarkable TOF of 510 h–1 with very low activation energy of 12 kJ mol−1, thus enhancing the catalytic conversion rate of CO2 into FA. Thus, this work demonstrates the MoS2/f-DSAC nanohybrid system as an efficient non-noble catalyst for converting CO2 into fuels.