Four-way purification of automobile exhaust over woody La0.8Ce0.2Fe0.3Co0.7O3 perovskite-type catalysts enhanced by NTP

In order to enhance the four-way purification performance of PM, NOx, CO and HC emitted by automobile exhausts over woody La0.8Ce0.2Fe0.3Co0.7O3 perovskite-type catalysts. First, the woody La0.8Ce0.2Fe0.3Co0.7O3 perovskite-type catalysts were modified by nonthermal plasma (NTP). The physicochemical properties of the catalyst surface were characterized utilizing x-ray diffractometer, Fourier-transform infrared spectroscopy, x-ray photoelectronic spectroscopy, scanning electron microscope and Brunauer-Emmett-Teller to analyze the effect of NTP on surface character of the catalyst samples. Second, NTP was combined with woody La0.8Ce0.2Fe0.3Co0.7O3 perovskite-type catalysts to form in-plasma catalysis purification (IPCP) systems. Finally, the four-way purification performance of perovskite-type catalysts were evaluated in the presence and absence of the plasma by simulation test bench. The results showed that NTP can enhance the four-way purification performance for PM, NOx, CO and HC emitted by automobile exhausts over woody La0.8Ce0.2Fe0.3Co0.7O3 perovskite-type catalysts. NTP can increase the specific surface area and porosity. When the input voltage, frequency and filling rate of IPCP systems are 15 kV, 15 Hz and 0.3, respectively, the maximum purification efficiency for PM, NOx, CO and HC are about 96%, 95%, 95%, and 84%. Moreover, four-way purification mechanism of IPCP was deduced according to the experimental results.