Design and fabrication of remote‐controllable micromachines by femtosecond laser‐induced two‐photon polymerization (TPP) of novel ferrofluids resin composed of methacrylate groups modified Fe3O4 nanoparticles and photoresists is demonstrated. As two typical models, a micro‐spring and a micro‐turbine were successfully fabricated for precise motion control. The development of remotely controllable micro‐nanomachines would shorten the distance between actionless micro‐nanostructures and smart microrobots.

Reported in this paper is two-photon photopolymerization (TPP) fabrication of magnetic microturbines with high surface smoothness towards microfluids mixing. As the key component of the magnetic photoresist, Fe(3)O(4) nanoparticles were carefully screened for homogeneous doping. In this work, oleic acid stabilized Fe(3)O(4) nanoparticles synthesized via high-temperature induced organic phase decomposition of an iron precursor show evident advantages in particle morphology. After modification with propoxylated trimethylolpropane triacrylate (PO(3)-TMPTA, a kind of cross-linker), the magnetic nanoparticles were homogeneously doped in acrylate-based photoresist for TPP fabrication of microstructures. Finally, a magnetic microturbine was successfully fabricated as an active mixing device for remote control of microfluids blending. The development of high quality magnetic photoresists would lead to high performance magnetically controllable microdevices for lab-on-a-chip (LOC) applications.

Reported here is a facile synthesis of nanoporous polymer chalk for painting superhydrophobic surfaces. Taking this nanoporous polymer as a media, superhydrophobicity is rapidly imparted onto three typical kinds of substrates, including paper, transparent polydimethylsiloxane (PDMS), and finger skin. Quantitative characterization showed that the adhesion between the water droplet and polymer-coated substrates decreased significantly compared to that on the original surface, further indicating the effective wetting mode transformation. The nanoporous polymer coating would open a new door for facile, rapid, safe, and larger scale fabrication of superhydrophobic surfaces on general substrates.

Negative differential resistance (NDR) is reported for a bilayer molecular junction. The system is comprised of a Hg–alkanethiol//arenethiol–Au bilayer molecular junction formed by bringing into contact a tetradecanethiol self-assembled monolayer (SAM)-coated drop of Hg with the surface of an oligo(phenylene-ethynylene) SAM on Au. Persistent, reproducible NDR is observed in the current–voltage characteristics with peak-to-valley ratios as high as 4.5 at room temperature. These results open a promising line of investigation of structure/function relationship and mechanisms in molecular NDR components.

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The electrocatalytic water splitting, which is driven by renewable energy input to produce oxygen, has been widely regarded as a promising strategy in the future energy portfolio. The two-dimensional structure...