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Abstract Biomorph actuators composed of two layers with asymmetric thermal expansion properties are widely explored owing to their high mechanical adaptability. Electrothermal nanomaterials are employed as the Joule heating components in them for controlled thermal expansion, while their large integration thickness often limits resulting actuation performances. This study reports high‐performance ultrathin soft biomorph actuators enabled by near atom‐thickness 2D platinum ditelluride (PtTe₂) layers—a new class of emergent metallic 2D transition metal dichalcogenides. The actuators employ wafer‐scale 2D PtTe₂layers sandwiched in between two polymer films of largely mismatched thermal expansion coefficients, which are electrically biased to generate Joule heating. This electrical‐to‐thermal conversion causes the asymmetric expansion of the polymers achieving outstanding actuation motions; i.e., large bending curvature, fast responsiveness, as well as high reversibility and endurance, which surpass the performances of previously explored graphene‐based actuators with much smaller dimensions. Furthermore, the 2D PtTe₂layers‐enabled actuators are demonstrated to function as soft grippers in lifting and relocating heavier objects, implying the great potential of near atom‐thickness materials in biomimetic devices. 

Abstract Heterogeneous integrations of functionally and chemically distinct materials have been explored to develop promising building blocks for opto‐electronic device applications. Recently, the Van der Waals (vdW)‐assembly of near atom thickness materials has provided excellent opportunities beyond what has been previously been difficult to realize. However, its up‐to‐date demonstrations remain far from achieving the scalability and versatility demanded for practical device applications, that is, the integration is generally demonstrated with intrinsically layered 2D materials of very small lateral dimensions. Herein, the large centimeter‐scale vdW assembly of two different materials with structurally, chemically, and functionally distinct properties, that is, 2D platinum ditelluride (PtTe₂) metallic multilayers and non‐layered 3D semiconducting platinum sulfide (PtS) are reported. Both materials are precisely delaminated from their growth wafers inside water and are subsequently integrated on unconventional substrates of desired functionalities. The large‐area vdW‐assembled 2D/3D PtTe₂/PtS hetero‐materials on flexible substrates exhibit an excellent photodetection in a spectral range of visible‐to‐near infrared (NIR) wavelength, which is well preserved under severe mechanical deformation. This study paves the way for exploring large‐area flexible opto‐electronic devices solely based on near atom thickness materials.