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A nanoforest of black silicon was prepared using a method combining aluminum-induced crystallization (AIC) and reactive-ion etching (RIE). During the AIC period, a rough layer, incorporating AlSix intermetallics, was formed. This layer acted as an etch mask for the RIE step. X-ray photoelectron spectroscopic (XPS) measurements were performed to further analyze the formation of black silicon. Compared to Si 3 N 4 and polysilicon, the black silicon exhibits a high degree of infrared absorption for wavelengths of about 3 to 5 μm and 8 to 14 μm, respectively. In addition, black platinum overlaid on the base of black silicon further improves the infrared absorption. This nanostructure forests of black silicon could be incorporated into the fabrication process for gas detectors, photovoltaic devices, and imaging applications to improve the infrared absorption characteristics.

This work highlights the results of a program currently underway to improve the voltage delay of aqueous magnesium (Mg) battery through pulse technique. The effect of current pulse on the electrochemical behavior of AZ31B Mg anode in aqueous solution is investigated using a multi-current step method and electrochemical impedance spectroscopy. Results indicate that the optimal pulse signal is 25 mA cm−2-100 ms and the excellent discharge behavior can be well maintained even at the 10 days immersion time. The surface morphology and chemical composition of the Mg anode are analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results demonstrate that the elimination of delayed action of the Mg electrode at controlled-pulse condition is to change the surface morphology distribution rather than the chemical composition. Finally, an evolutionary model of the surface film is proposed.

In this paper, a three-gas detection system with a environmental parameter compensation method is proposed based on Non-dispersive infra-red (NDIR) technique, which can be applied to detect multi-gas (methane, carbon dioxide and carbon monoxide). In this system, an IR source and four single-channel pyroelectric sensors are integrated in the miniature optical gas chamber successfully. Inner wall of the chamber coated with Au film is designed as paraboloids. The infrared light is reflected twice before reaching to detectors, thus increasing optical path. Besides, a compensation method is presented to overcome the influence in variation of environment (ambient temperature, humidity and pressure), thus leading to improve the accuracy in gas detection. Experimental results demonstrated that detection ranges are 0–50,000 ppm for CH 4 , 0–44,500 ppm for CO, 0–48,000 ppm for CO 2 and the accuracy is ±0.05%.