Controlled droplet manipulation by light has tremendous technological potential. We report here a method based on photothermally induced pyroelectric effects that enables manipulation and maneuvering of a water droplet on a superhydrophobic surface fabricated on lithium tantalite (LiTaO3). In particular, we demonstrate that the pyroelectric charge distribution has an essential role in this process. Evenly distributed charges promote a rapid hydrophobic to hydrophilic transition featuring a very large water contact angle (WCA) change of ∼76.5° in air. This process becomes fully reversible in silicone oil. In contrast, the localized charge distribution induced by guided laser illumination leads to very different and versatile functionalities, including droplet shape control and motion manipulation. The influence of a saline solution is also investigated and compared to the deionized water droplet. The focusing effect of the water droplet, a phenomenon that widely exists in nature, is particularly of interest. Simple tuning of the laser incident angle results in droplet deformation, jetting, splitting, and guided motion. Potential applications, such as droplet pinning and transfer, are presented. This approach offers a wide range of versatile functionalities and ready controllability, including contactless, electrodeless, and precise spatial and fast temporal control, with tremendous potential for applications requiring remote droplet control.

Low-cost, high-quality, and large-area superhydrophobic surfaces are in high demand. This study demonstrates laser-engineered polydimethylsiloxane (PDMS) as a platform for versatile and highly efficient water manipulation. The fabrication process consists of two steps: patterning PDMS with arrayed microlenses and laser pulse scanning. The obtained PDMS is superhydrophobic and exhibits excellent chemical resistance, UV stability, pressure robustness, and substantial mechanical durability. Notably, there is no significant change in the water contact angles after storage in air for 14 months. Microstructural analysis revealed that the sample contained stable nanostructured inorganics such as crystalline silicon, silicon carbide, and sp3-like carbon. The superhydrophobic surface was demonstrated to have versatile and wide applications in oil/water separation and water collection.

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oxidase has opened up the horizon for continuous glucose monitoring. However, enzymatic glucose sensors showcase slow response, low sensitivity, complex immobilization process, and they are susceptible to temperature, humidity, and pH variations. [5][6][7] Therefore, the development of fabrication methods for high-performance nonenzymatic glucose sensors needs to be explored.In nonenzymatic glucose sensors, catalytic sensing is performed using transition metals immobilized on conductive substrates. [8,9] The role of transition metals is demonstrated in the recently established d-band model, in which the d-band center of the transition metal serves as an electronic descriptor to evaluate the binding strength of the reaction intermediate on the metal. [10,11] When the adsorbate molecule approaches the metal surface, its energy levels are shifted by the metal electrons. Although the wide s-band of the metal only shifts and broadens the electronic state of the molecule, [12] the narrow d-band with large density of states (DOS) splits the electronic state of the molecule into bonding and antibonding states, which determine the chemisorption and desorption processes. As a result, the d-band center can be adopted as a descriptor to evaluate catalytic performance. [13,14] Among all transition metals, Cu is one of the most widely utilized transition metal catalysts, offering great potential as an ideal electrocatalyst for glucose oxidation. [9,15] The sensing capability of an electrocatalyst is affected by its support material. [16,17] In comparison with conductive carbonbased materials such as graphene [18] and carbon nanotubes, [16] boron-doped diamond (BDD) has a wide semiconductor bandgap (E g = 5.47 eV), wide electrochemical window, and excellent stability. Thus, it serves as an ideal electrode material for sensing applications that demand low background currents and high signal-to-noise (S/N) ratios. [19,20] For instance, Pinar et al. [21] achieved the simultaneous detection of epinephrine and lidocaine using a BDD electrode by taking advantage of its wide electrochemical window. The high S/N ratio of BDD electrodes enables electrophysiological recording, dopamine sensing, [22] and real-time drug tracking. [23] However, because BDD is electrochemically inert and has poor glucose sensitivity, decorating BDD electrodes with transition metals may offer a unique opportunity for the development of glucose sensors with ultrahigh sensitivity and improved stability. Robust and high-performance electrochemical electrodes for non-enzymatic glucose sensing are in constant demand. Herein, a hierarchical nonenzymatic glucose sensing electrode on boron-doped diamond (BDD) is fabricated using high-speed laser engraving and pulsed electrodeposition of Cu nanostructures. The obtained electrode contains a densely packed Cu nanoflake (CuNF) array periodically decorated on the laser-engraved BDD. The hierarchical nanoarchitecture combines the d-band catalytic activity of the CuNFs with the low capacitive background current of the engra...

We explore in this paper the photoinduced wetting/dewetting behaviors of silver/rutile heterointerfaces and demonstrate that silver nanoparticles can greatly increase the ultraviolet induced wetting and infrared induced dewetting transition rates. The results are interpreted based on the examination of the defect structures of the rutile surface before and after ultraviolet irradiation. The density functional theory calculation with the inclusion of the on-site Coulomb interaction reveals that the formation energy of an oxygen vacancy on the silver/rutile (110) interface is lower than that on the blank rutile (110) surface. We also discover that plasmonic nanostructures enable the partial wetting transition of the rutile (110) surface by irradiation with visible light at 473 nm and 532 nm. This work opens up a feasible route to the development of high-performance multifunctional materials via plasmonic nanostructures and defect engineering.