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Van der Waals (vdW) integration affords semiconductor heterostructures without constrains of lattice matching and opens up a new realm of functional devices by design. A particularly interesting approach is the electrochemical intercalation of two-dimensional (2D) atomic crystal and formation of superlattices, which can provide scalable production of novel vdW heterostructures. However, this approach has been limited to the use of organic cations with non-functional aliphatic chains, therefore failed to take the advantage of the vast potentials in molecular functionalities (electronic, photonic, magnetic, etc.). Here we report the integration of 2D crystal (MoS 2 , WS 2 , highly oriented pyrolytic graphite (HOPG), WSe 2 as model systems) with electrochemically inert organic molecules that possess semiconducting characteristics (including perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA), pentacene and fullerene), through on-chip electrochemical intercalation. An unprecedented long-range spatial feature of intercalation has been achieved, which allowed facile assembly of a vertical MoS 2-PTCDA-Si junction. The intercalated heterostructure shows significant modulation of the lateral transport, and leads to a molecular tunneling characteristic at the vertical direction. The general intercalation of charge neutral and functional molecules defines a versatile platform of inorganic/organic hybrid vdW heterostructures with significantly extended molecular functional building blocks, holding great promise in future design of nano/quantum devices.

S1S1 Changes in measured RO2 and closed-shell products as a function of the reacted α-pinene.The changes of selected RO2 and the corresponding closed-shell monomers and dimers as a function of the reacted α-pinene are consistent with previous studies (Figure S7) (Zhao et al., 2018). The RO2 concentration increases rapidly when the reacted α-pinene is relatively low, and the increasing rate slows down due to the elevated removal rate of RO2 via cross-reactions at higher reacted α-pinene (> 20 ppb). The dimers exhibit opposite trends with RO2. As the reacted α-pinene increases, the increasing rates of the dimers become slightly higher due to the promoted RO2 cross-reactions. As for the HOM monomers, their concentrations basically show linear correlations with increasing reacted α-pinene. S2Table S1 Summary of experimental conditions of α-pinene ozonolysis with the addition of NO2.