| Recently, nanogenerator(NG) has been newly invented to convert ambient mechanical energy into electricity. Outstanding progress has been made in developing PDMS-based NGs with different materials, but the output current and output power of these devices are relatively low, and this insufficient power output probably limits their practical application. Therefore, improvement of the output current and power is an urgent need to meet the demand of current special field.In this paper, we have synthesized Zn O nanotubes and Ag nanowires, and used them to fabricate Ag/Zn O/Ag piezoelectric NG, then we modified PDMS with lateral Zn O nanotubes and Ag nanowires, and fabricate PDMS-based triboelectric NGs with different structure, realized the great improvement of output current of NG and made a certain research progress. The main results are summarized as follows:① Piezoelectric NGs based on Ag/Zn O/Ag structure1) Zn O nanotube arrays have been synthesized from Zn(NO3)2·6H2O and C6H12N4 solution with concentration of 30 m M on a gold-plated silicon wafer at 100 ℃ for 3 h then 55 ℃ for 21 h by hydrothermal synthesis method. Sanning electron microscopy(SEM) images show that the inner and outer diameters of Zn O nanotubes are about 500 nm and 300 nm, respectively. The growth mechanism of Zn O nanotubes is further analyzed.2) Ag nanowires have been synthesized from ethylene glycol at 160 ℃ with Ag NO3 and PVP solution injected into it at the same time then continue heating and stirring for 60 min. SEM images show that the diameter and length of Ag nanowires are approximately 100 nm and 50 μm. The growth mechanism of Ag nanowires is further analyzed.3) Ag/Zn O/Ag NGs based on the as-synthesized Zn O nanotubes and Ag nanowires have been fabricated and measured using a generator test system(an electric oscillator(JZK-5), a Stanford low-noise current preamplifier(Model SR570), a Data Acquisution Card(NI PCI-6259) and so on). The output current of Ag/Zn O/Ag NG is proved to be 450 n A, further verifies the good piezoelectricity of Zn O nanotubes.② PDMS-Based triboelectric NGs with different structures1) Four kinds of PDMS-Based triboelectric NGs that are respectively PDMS/PDMS, PDMS/Zn O/PDMS, PDMS/Ag/PDMS and PDMS/Ag/Zn O/PDMS are fabricated and measured using a generator test system. The output current of four kinds of NGs with 2 cm×2 cm can reach as high as 2 μA, 6.5 μA, 14 μA and 23 μA, respectively. Prove the unique advantages of PDMS/Ag/Zn O/PDMS layered structure in improving output current of NG.2) We study the effect of thickness, size and measure frequency on the output performance of PDMS/Ag/Zn O/PDMS NG(2 cm×2 cm). It proves that the NG with thinner PDMS thickness and larger size can produce the greater output current, and the device gives the maximum output current at the frequency of 1.7 Hz. We further tested the open-circuit voltage of the PDMS/Ag/Zn O/PDMS NG and it could be reached 350 V. The output voltage, current and power of the NG are also measured under different external loads, and the maximum output power of 4.3 m W is achieved with an external load of 2.02×107 ohm.3) The potential distribution in PDMS/Ag/PDMS NG and PDMS/Ag/Zn O/PDMS NG are simulated by using the finite element method. The result displays the potential difference in PDMS/Ag/Zn O/PDMS NG is larger than that PDMS/Ag/PDMS NG, which is consistent with our experiment results. |
PDF Full Text Request