Layered indium selenide (InSe) is an emerging two-dimensional semiconductor that has shown significant promise for high-performance transistors and photodetectors. The range of optoelectronic applications for InSe can potentially be broadened by forming mixed-dimensional van der Waals heterostructures with zero-dimensional molecular systems that are widely employed in organic electronics and photovoltaics. In a 5 PI collaboration within NU-MRSEC IRG-1, photoinduced charge separation is probed between InSe and two organic molecular semiconductors using novel experimental techniques that combine laser illumination with conductive scanning probe microscopy. In addition to providing insight for mixed-dimensional InSe-organic van der Waals heterostructures, this work establishes a general experimental methodology for studying localized charge transfer at the molecular scale that is applicable to other photoactive nanoscale systems.

ACS Nano, 14, 3509 (2020).