In the paper, we developed an in situ diffusion growth method to fabricate porous Fe2(MoO4)3 nanorods. The average diameter and the length of the porous nanorods were 200 nm and 1.2-4 μm, respectively. Moreover, many micropores existed along axial direction of the Fe2(MoO4)3 nanorods. In terms of nitrogen adsorption-desorption isotherms, calculated pore size was in the range of 4-115 nm, agreeing well with the transmission electron microscope observations. Because of the uniquely porous characteristics and catalytic ability at low temperatures, the porous Fe2(MoO4)3 nanorods exhibited very good H2S sensing properties, including high sensitivity at a low working temperature (80 °C), relatively fast response and recovery times, good selectivity, and long-term stability. Thus, the porous Fe2(MoO4)3 nanorods are very promising for the fabrication of high-performance H2S gas sensors. Furthermore, the strategy presented here could be expended as a general method to synthesize other hollow/porous-type transition metal molybdate nanostructures by rational designation in nanoscale.

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Hierarchical nanoarchitectures constructed by MoO 2 nanocrystalfunctionalized graphene were fabricated through an in situ reduction process. As an anode, even at a 10C (0.1 h per half cycle) charging-discharging rate, the reversible capacity is much higher than the theoretical capacity of graphite. Thus, rapid charging-discharging of the anodes is achieved by the nanoarchitectures.

The all temperature range stability is the most important technology of MEMS angular velocity sensor according to the principle of capacity detecting. The correlation between driven force and zero-point of sensor is summarized according to the temperature characteristic of the air-damping and resonant frequency of sensor header. A constant trans-conductance high-linearity amplifier is designed to realize the low phase-drift and low amplitude-drift interface circuit at all-temperature range. The chip is fabricated in a standard 0.5 [Formula: see text] CMOS process. Compensation achieved by driven force to zero-point drift caused by the stiffness of physical construction and air-damping is adopted. Moreover, the driven force can be obtained from the drive-circuit to avoid the complex sampling. The test result shows that the zero-point drift is lower than 30[Formula: see text]/h (1-sigma) at the temperature range from −40[Formula: see text]C to 60[Formula: see text]C after three-order compensation made by driven force.

A high performance interface circuit of sigma-delta accelerometer with low harmonic distortion used many kinds of circuit processing techniques is presented in this work. Multi-bit, dynamic element matching, correlated-double-sampling and electrostatic force feedback linearization circuit are used simultaneously in order to achieve the design indicators. Because of the usage of multi-bit, the design to operational amplifier (OPA) becomes easier, and only a single-stage folded-cascode amplifier is used in the modulator, the OSR is only 64. It highly reduced the difficulty of circuit. The test results indicate that the chip area is only about 10 mm 2 and the power dissipation is 10 mW with a sampling frequency of 60 kHz. The dynamic range (DR) of the system can be lower than −130 dB, the SNR and SNDR reach to −120 dB and −110 dB respectively with a resolution about 17 bits when referred to 3g full scale DC acceleration under CMOS 0.5 µm process. The dc nonlinearity of it is 0.2%. This paper realizes an approach which can both simplify the design of the interface circuit and improve the performance of it.