In this study, the transfer method is employed to add hydrophilic SiO2 nanopowders to a Pt/C catalyst ink to form an anode catalyst layer on a proton exchange membrane (PEM). The SiO2-layered membrane electrode assemb...In this study, the transfer method is employed to add hydrophilic SiO2 nanopowders to a Pt/C catalyst ink to form an anode catalyst layer on a proton exchange membrane (PEM). The SiO2-layered membrane electrode assembly improves the performance of the PEM under low- or zero-humidification conditions. When the PEM fuel cell (PEMFC) undergoes electrochemical reaction, the moisture content of the PEM exhibits a substantial influence on the transmission of protons. To ensure the moisture content remains high, an external humidifier is typically employed to humidify the majority of PEMFCs. However, self-humidifying PEMFCs could utilize the water produced by the fuel cell reaction, thereby eliminating the need for an external humidifier. In this study, various SiO2 loadings were added to an anode catalyst layer, and the cell temperature and gas humidification conditions were adjusted to determine the influence of the SiO2 loadings on the fuel cell performance. The results show that adding SiO2 is preferable to not adding SiO2 when the fuel cell temperature is 50°C.展开更多
CrAlSiN with thickness up to 16 μm was deposited on tungsten carbide via multi-deposition process by cathode arc deposition technique. Scratch and water-sand jet impingement erosion tests were carried out to evaluate...CrAlSiN with thickness up to 16 μm was deposited on tungsten carbide via multi-deposition process by cathode arc deposition technique. Scratch and water-sand jet impingement erosion tests were carried out to evaluate the adhesion by determining the worn surface of the coatings. Results showed that the failure mode of the adhesion can be concluded that the weak bond of each CrAlSiN layer as compared to the strong bond between the coating and substrate. The average surface roughness of the coatings before the erosion test was about the same level. After the erosion test of 30 minutes, the eroded CrAlSiN coatings exhibited improved average surface roughness as compared to the original CrAlSiN coatings. Further increasing the erosion up to 60 minutes, the wear and minor peeling of the CrAlSiN coating between each layer was observed. A further research to improve the bond strength between each layer was needed.展开更多
文摘In this study, the transfer method is employed to add hydrophilic SiO2 nanopowders to a Pt/C catalyst ink to form an anode catalyst layer on a proton exchange membrane (PEM). The SiO2-layered membrane electrode assembly improves the performance of the PEM under low- or zero-humidification conditions. When the PEM fuel cell (PEMFC) undergoes electrochemical reaction, the moisture content of the PEM exhibits a substantial influence on the transmission of protons. To ensure the moisture content remains high, an external humidifier is typically employed to humidify the majority of PEMFCs. However, self-humidifying PEMFCs could utilize the water produced by the fuel cell reaction, thereby eliminating the need for an external humidifier. In this study, various SiO2 loadings were added to an anode catalyst layer, and the cell temperature and gas humidification conditions were adjusted to determine the influence of the SiO2 loadings on the fuel cell performance. The results show that adding SiO2 is preferable to not adding SiO2 when the fuel cell temperature is 50°C.
文摘CrAlSiN with thickness up to 16 μm was deposited on tungsten carbide via multi-deposition process by cathode arc deposition technique. Scratch and water-sand jet impingement erosion tests were carried out to evaluate the adhesion by determining the worn surface of the coatings. Results showed that the failure mode of the adhesion can be concluded that the weak bond of each CrAlSiN layer as compared to the strong bond between the coating and substrate. The average surface roughness of the coatings before the erosion test was about the same level. After the erosion test of 30 minutes, the eroded CrAlSiN coatings exhibited improved average surface roughness as compared to the original CrAlSiN coatings. Further increasing the erosion up to 60 minutes, the wear and minor peeling of the CrAlSiN coating between each layer was observed. A further research to improve the bond strength between each layer was needed.
