We report for the first time that conducting objects could be propelled in folded liquid filled channels by bipolar electrochemistry.

Au–Fe/Ni/(Mo/Co) alloy microsphere motors (AMSM), having an average diameter of 7~9μm, were fabricated though a rapid and effortless method than the template direct electroplating (TDEP), which only requires physical vapor deposition (PVD) of inert metal coat on commercially available microspheres; thus, several kinds of AMSM with different alloy composition can be manufactured readily. Via co-catalytic decomposing reaction in the mixed fuel of hydrogen peroxide and hydrazine, the ejection of oxygen bubbles generated from the Fe/Ni/(Mo/Co) alloy hemisphere provides a powerful directional propulsion. The AMSM's moving ability closely depends upon the content of mixed fuel and the composition of alloy, especially the content of nickel. The AMSM can move as fast as 548.63μm/s (ca. 64 body-lengths/s). Because of the permalloy composition, the AMSM also can be guided by the magnetic force besides controlled with the propelling force generated by the bubble thrust. Compared with the nanowire motor, the AMSM could facilitate different biomedical applications, such as targeted drug delivery in future research, because of its bigger specific surface area.

Hydrazine in mixed fuels facilitates the oxidation of H2O2 to oxygen bubbles that propel the Au–Fe/Ni nanomotors.

This was the first report on the ECL of semiconductor nanocrystals involving three elements and dealt with amorphous nanomaterials.

Au-Fe/Ni alloy nanowire motors, having an average length of 5.4 +/- 1.2 mu m and a diameter of 280 +/- 10 nm, can move fast in a mixed fuel containing H2O2 and N2H4. The powered motion is attributed to the bubble thrust produced from catalytic decomposition of hydrogen peroxide on the Fe/Ni alloy segments, while hydrazine seems to act as a co-catalyst. The regulation of speed can be achieved by modulating the proportion of alloy composition, and the highest speed obtained is up to 850 mu m s(-1) (ca. 157 body-length per s), which is the fastest among all nanowire motors. Because of the ferronickel segment's magnetism, the Au-Fe/Ni alloy nanomotors also can be guided by the magnetic force, in addition to being controlled by the propelling force generated by the bubble thrust.

The recently reported shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS) is considered as the next generation of advanced spectroscopy for its surface and molecular generality. With the aim to utilize the virtues of shell‐isolated strategy and advance the SHINERS technique, we introduce a silane‐based rapid synthesis method of silica‐coating Au nanorods (Au@SiO 2 NRs) with manoeuvrable ultra‐thin shell and tunable SPR. The results demonstrate that the SPR of Au NRs could be optimized to obtain large Raman enhancement using either 633 nm or 785 nm laser. Differing from previously reported Au@SiO 2 NRs synthesis method, we can tune the silica shell thickness within several nanometers to maximize the Raman signal while effectively eliminating the exterior interference. And this advanced synthesis method has also significantly reduced the silica‐coating time from one day to ca. 1 h. This method as a new development of SHINERS technique has successfully got enhanced signal in solution Raman tests of malachite green, giving a great potential to be extended to in‐situ measurement for daily life detection. Copyright © 2013 John Wiley & Sons, Ltd.

We report the visual detection of Al3+ using unlabeled gold nanoparticles (AuNPs) based on the complexation of Al3+ with citric acid, resulting in the aggregation of AuNPs. The distinction of color change can be observed by the naked eye at concentrations down to 1.0 μM which is lower than the permissable level (7.4 μM) for drinking water as defined by the World Health Organization.