Si-Cong Tan

Magnetic trap effect to restrict motion of self-powered tiny liquid metal motors

We reported a phenomenon that the magnetic field can make up a boundary to restrict motion of the aluminum powered liquid metal motor. For the droplet motors with diameter below 1 mm, such magnetic trap effect will be strong enough to bounce them off the boundary. We attributed the effect to the electromagnetic mechanism. Owing to the Lorentz force, the high magnetic field will break up the directional running of the motor. The more aluminum added in the metal droplet, the stronger the trap effect. This phenomenon suggests an important way to control behavior of the liquid metal motors.

Self‐Propelled and Long‐Time Transport Motion of PVC Particles on a Water Surface

Driven by the Marangoni effect, a poly(vinyl chloride) (PVC) particle runs in its orbit (a) with high velocity due to the release of surfactant and heat. The PVC particles are also able to efficiently drive an aluminum bulk and to induce spinning and quick runs on a water surface (b).

Generation of diamond nuclei on amorphous SiO2 by alternating‐current bias microwave plasma chemical vapor deposition

The nucleation of diamond on the amorphous SiO2 mirror surface has been achieved by means of adding an ac signal to the negative dc bias in the microwave plasma chemical vapor deposition. It is found in experiment that the nucleation of diamond happens only after the frequency of the ac signal exceeds a threshold. The results also show that the diamond nucleation density depends not only on the ac frequency but also on the magnitudes of the ac signal and the dc bias.

Controlled hydrogen generation using interaction of artificial seawater with aluminum plates activated by liquid Ga–In alloy

Recent studies have disclosed that liquid metal (Ga–In alloy) can be applied to activate aluminum in electrolytes to generate hydrogen at room temperature. To present a close to reality experimental demonstration of this method and to realize a continuous reaction between an Al plate and seawater, the liquid metal GaIn10 alloy is adopted to directly erode the surface of the Al plate. Then the eroded Al plate is immersed into NaCl solution (simulated seawater) to produce hydrogen. The results indicate that the existence of gallium can accelerate the average H2 production rate. In addition, the average hydrogen generation rate increased from 3 × 10−5 L s−1 to 4.5 × 10−4 L s−1 as the temperature rose from 20 °C to 80 °C when the corrosion area of the Al plates was 1 × 10−4 m2. However, the H2 production first increased and then decreased with the increase of NaCl concentration. The average hydrogen generation effectiveness is 0.71 L g−1 in the aluminum–water reaction in 5% NaCl solution at 20 °C within 20 min. Over the experimental process, the capability of producing hydrogen has a linear relationship with the corrosion area on the surface of the Al plates corroded by the liquid metal. This work suggests good prospects in the future practice of large-scale hydrogen generation using Al and seawater as reaction sources.