Solution-processed semiconducting transition metal dichalcogenides (TMDs) are at the centre of an ever-increasing research effort in printed (opto)electronics. However, device performance is limited by structural defects resulting from the exfoliation process and poor inter-flake electronic connectivity.Here, we report a new molecular strategy to boost the electrical performance of TMD-based devices via the use of dithiolated conjugated molecules, to simultaneously heal sulfur vacancies in solutionprocessed transition metal disulfides (MS2) and covalently bridge adjacent flakes, thereby promoting percolation pathways for the charge transport. We achieve a reproducible increase by one order-ofmagnitude in field-effect mobility (µFE), current ratios (ION / IOFF), and switching times (τS) of liquid-gated transistors, reaching 10 -2 cm 2 V -1 s -1 , 10 4 , and 18 ms, respectively. Our functionalization strategy is an universal route to simultaneously enhance the electronic connectivity in MS2 networks and tailor on demand their physicochemical properties according to the envisioned applications.

Liquid phase exfoliation (LPE) is the principal method of producing two-dimensional (2D) materials such as graphene in large quantities with a good balance between quality and cost, and is now widely adopted by both the academic and industrial sectors. The fragmentation and exfoliation mechanisms involved have usually been simply attributed to the force induced by ultrasound and the interaction with the solvent molecules. Nonetheless, little is known about how they actually occur, i.e. how a thick and large graphite crystals can be exfoliated into thin and small graphene flakes. Here we demonstrate that during ultrasonic LPE, the transition from graphite flakes to graphene takes place in three distinct stages. Firstly, sonication leads to the rupture of large flakes and the formation of kink band striations on the flake surfaces, primarily along zig-zag directions. Secondly, cracks form along these striations, and together with intercalation of solvent, lead to the unzipping and peeling off of thin graphite strips that in the final stage are exfoliated into graphene. The findings will be of great value in the quest to

The ongoing miniaturization of devices and development of wireless and implantable technologies demand electromagnetic interference (EMI)‐shielding materials with customizability. Additive manufacturing of conductive polymer hydrogels with favorable conductivity and biocompatibility can offer new opportunities for EMI‐shielding applications. However, simultaneously achieving high conductivity, design freedom, and shape fidelity in 3D printing of conductive polymer hydrogels is still very challenging. Here, an aqueous Ti3C2‐MXene‐functionalized poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate ink is developed for extrusion printing to create 3D objects with arbitrary geometries, and a freeze–thawing protocol is proposed to transform the printed objects directly into highly conductive and robust hydrogels with high shape fidelity on both the macro‐ and microscale. The as‐obtained hydrogel exhibits a high conductivity of 1525.8 S m–1 at water content up to 96.6 wt% and also satisfactory mechanical properties with flexibility, stretchability, and fatigue resistance. Furthermore, the use of the printed hydrogel for customizable EMI‐shielding applications is demonstrated. The proposed easy‐to‐manufacture approach, along with the highlighted superior properties, expands the potential of conductive polymer hydrogels in future customizable applications and represents a real breakthrough from the current state of the art.