Precision manipulation of various liquids is essential in many fields. Unlike solid objects, fluids are intrinsically divisible, enriching their fundamental operations with merging, dispensing, and splitting on top of moving. Fluids are sticky as well, calling for their lossless manipulation to prevent mass loss and contamination. We present photopyroelectric microfluidics that meet all the requirements. In response to the irradiation from even one single beam of light, our platform creates a unique wavy dielectrophoretic force field that is remarkably capable of performing desired loss-free (loss being 0.5% of existing one) manipulation of droplets of surface tension from 18.9 to 98.0 mN m−1 and volume from 1 nl to 1000 μl, functioning as a “magic” wetting-proof hand to navigate, fuse, pinch, and cleave fluids on demand, enabling cargo carriers with droplet wheels and upgrading the limit of maximum concentration of deliverable protein by 4000-fold.

Since the first discovery of graphene, 2D materials are drawing tremendous attention due to their atomic thickness and superior properties. Fabrication of high-quality micro-/nanopatterns of 2D materials is essential for their applications in both nanoelectronics and nanophotonics. In this work, an all-optical lithographic technique, optothermoplasmonic nanolithography (OTNL), is developed to achieve high-throughput, versatile, and maskless patterning of different atomic layers. Low-power (≈5 mW µm −2 ) and high-resolution patterning of both graphene and MoS 2 monolayers is demonstrated through exploiting thermal oxidation and sublimation at the highly localized thermoplasmonic hotspots. Density functional theory simulations reveal that Au nanoparticles reduce the formation energy (≈0.6 eV) of C monovacancies through bonding between undercoordinated C and Au, leading to a significant Au-catalyzed graphene oxidation and a reduction of the required laser operation power. Programmable patterning of 2D materials into complex and large-scale nanostructures is further demonstrated. With its low-power, high-resolution, and versatile patterning capability, OTNL offers the possibility to scale up the fabrication of nanostructured 2D materials for many applications in photonic and electronic devices.

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