Isomerization behavior of p-aminoazobenzene directly anchored on MoS2/graphene oxide nanocomposite

Abstract Introducing novel nanomaterials into azobenzene (AB) and its derivatives enables a remarkable influence on the molecular isomerization and thus is of great interest for a variety of applications. We systematically study the thermal and photoinduced isomerization of p-aminoazobenzene (pAAB) directly anchored on MoS2/GO nanocomposites by employing in-situ and real-time surface-enhanced Raman scattering (SERS) spectroscopy. The MoS2/GO nanocomposite provides the enhancements for the thermal isomerization efficiency of pAAB of more than 3-fold compared with that of the bare pAAB. We also show that the MoS2/GO nanocomposite has little impact on the UV-induced isomerization of the pAAB, but has apparent impact on the reverse cis-to-trans isomerization of the pAAB under blue light illumination. The results reveal that the effect of MoS2/GO nanocomposite on the photoinduced isomerization of pAAB depends on irradiation wavelength, which can be attributed to the competing interplay of charge transfer and structural relaxation in the hybrid system composed of pAAB and MoS2/GO nanocomposites. The study helps elucidate how the isomerization of azobenzene molecules is affected as incorporated into nanoscale assemblies, and thus open new opportunities for the applications of the isomerization of azobenzene in complex hybrid nanodevices.