A switchable diode in a 2D semiconductor-molecular junction heterostructure is reported. MoS2 is exfoliated on top of a monolayer of azobenzene-substituted thiols on gold. Photoisomerization of the azobenzenes results in switching between a rectifier with rectifying ratios of 10(4) and a conductive state, as revealed by conducting atomic force microscopy.

Reversible work function changes induced by photoisomerization of asymmetric azobenzene dithiol selfassembled monolayers on gold Appl. Phys. Lett. 93, 083109 (2008); 10.1063/1.2969468Monolayer alignment on azobenzene surfaces during UV light irradiation: Analysis of optical polarized absorption measurement results and theoretical treatment