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Rapid surface functionalization of nanomaterials using covalent linkage following “green chemistry” remains challenging, and the quest for developing simple protocols is persisting. We report a nanomechanical microfluidic approach for the coupling of allenamide functionalized organic derivatives on the surface of thiol-modified silica nanoparticles using allenamide-thiol chemistry. The coupling principle involves the use of a microfluidic surface acoustic wave device that generates acoustic streaming-based chaotic fluid micromixing that enables mixing of laterally flowing fluids containing active components. This approach was used to demonstrate the direct surface labeling of thiol-modified silica nanoparticles using a selected group of modified fluorescent tags containing allenamide handles and achieved a total labeling efficiency of 83–90%. This green approach enabled a highly efficient surface functionalization under aqueous conditions, with tunable control over the conjugation process via the applied field. The dye-labeled silica particles were characterized using various analytical techniques and found to be biocompatible with potential in live cell bioimaging. It is envisaged that this bioconjugation strategy will find numerous applications in the field of bioimaging and drug delivery.

Formamidinium lead halide perovskite nanoparticles (FAPbBr3NPs), because of their prominent piezoelectric properties, have drawn increasing attention in the fields of piezoelectric applications. Remarkable enhancement of piezoelectric power output is achieved from a piezoelectric composite nanogenerator by combining the FAPbBr3NPs with poly(vinylidene fluoride) (PVDF) polymer. The FAPbBr3NPs @ PVDF composite based piezoelectric nanogenerators show the highest outstanding outputs with voltage of 30V and current density of 6.2μAcm−2for organic-inorganic lead halide perovskite material based devices. The improved performance can be ascribed to the using of PVDF, piezoelectric polymer as matrix, as well as the homogeneous distribution of FAPbBr3NPs with enhanced stress on piezoelectric nanoparticles. The alternating energy generated from the nanogenerator can be utilized to charge a capacitor through a bridge rectifier and light up a commercial light-emitting diode (LED). Our obtained results open the feasibility of organic-inorganic lead halide perovskite materials for the design and development of high-efficiency energy harvesting applications.