Abstract Cathode catalysts comprising composite NiO, NiO-Pt, or LiNiO2 have been developed for electro- chemical oxidation of hydrogen sulfide in intermediate-temperature solid oxide fuel cells （ITSOFCs）. All cataly...Abstract Cathode catalysts comprising composite NiO, NiO-Pt, or LiNiO2 have been developed for electro- chemical oxidation of hydrogen sulfide in intermediate-temperature solid oxide fuel cells （ITSOFCs）. All catalysts exhibited good electrical conductivity and catalytic activity at operating temperature. Composite NiO catalysts were found to be more active and have lower over potential and higller current density than pure Pt although the electrical conductivity of NiO itself is lower than that of Pt. This problem has been overcome by either admixing as high as 10% （by mass）Ag powder into NiO_ cathode layer or using composite NiO c atalysts such as NiO-Pt and LiNiO2 catalysts. Composite catalysts like NiO with Ag, electrolyte and starch admixed, NiO-Pt, which was prepared from a mixture of NiO and Pt powders, by admixing electrolyte and starch, and LiNiO2, which is derived from the reaction of LiOH-H2O and NiO with electrolyte and starch admix_ed have been shown to be feasible and effective in an intermediate-temperature H2S-air fuel cell. A fuel cell using Li2SO4-based proton-conducting membrane as electrolyte, metal sulfides as anode catalysts, and composite NiO as cathode catalysts produced a maximum current density about 300mA·cm^-2 and maximum power density over 80 mW-cm-2 at 680℃.展开更多
A positive-electrolyte-negative(PEN)assembly solid oxide fuel cell(SOFC)with a thin electrolyte film for intermediate temperature operation was fabricated.Instead of the traditional screen-printing method,both anode a...A positive-electrolyte-negative(PEN)assembly solid oxide fuel cell(SOFC)with a thin electrolyte film for intermediate temperature operation was fabricated.Instead of the traditional screen-printing method,both anode and cathode catalysts were pressed simultaneously and formed with the fabrication of nano-composite electrolyte by press method.This design offered some advantageous configura-tions that diminished ohmic resistance between electrolyte and electrodes.It also increased the proton-conducting rate and improved the performance of SOFCs due to the reduction of membrane thickness and good contact between electrolyte and electrodes.The fabricated PEN cell generated electricity between 600℃ and 680℃ using H2S as fuel feed and air as oxidant.Maximum power densities 40 mW·cm^(-2) and 130 mW·cm^(-2) for the PEN configuration with a Mo-Ni-S-based composite anode,nano-composite electrolyte(Li_(2)SO_(4)+Al_(2)O_(3))film and a NiO-based composite cathode were achieved at 600℃ and 680℃,respectively.展开更多
基金Supported by the Natural Science Foundation of Guangdong Province （No.05006552）.
文摘Abstract Cathode catalysts comprising composite NiO, NiO-Pt, or LiNiO2 have been developed for electro- chemical oxidation of hydrogen sulfide in intermediate-temperature solid oxide fuel cells （ITSOFCs）. All catalysts exhibited good electrical conductivity and catalytic activity at operating temperature. Composite NiO catalysts were found to be more active and have lower over potential and higller current density than pure Pt although the electrical conductivity of NiO itself is lower than that of Pt. This problem has been overcome by either admixing as high as 10% （by mass）Ag powder into NiO_ cathode layer or using composite NiO c atalysts such as NiO-Pt and LiNiO2 catalysts. Composite catalysts like NiO with Ag, electrolyte and starch admixed, NiO-Pt, which was prepared from a mixture of NiO and Pt powders, by admixing electrolyte and starch, and LiNiO2, which is derived from the reaction of LiOH-H2O and NiO with electrolyte and starch admix_ed have been shown to be feasible and effective in an intermediate-temperature H2S-air fuel cell. A fuel cell using Li2SO4-based proton-conducting membrane as electrolyte, metal sulfides as anode catalysts, and composite NiO as cathode catalysts produced a maximum current density about 300mA·cm^-2 and maximum power density over 80 mW-cm-2 at 680℃.
基金supported by the Natural Science Foundation of Guangdong Province(No.05006552).
文摘A positive-electrolyte-negative(PEN)assembly solid oxide fuel cell(SOFC)with a thin electrolyte film for intermediate temperature operation was fabricated.Instead of the traditional screen-printing method,both anode and cathode catalysts were pressed simultaneously and formed with the fabrication of nano-composite electrolyte by press method.This design offered some advantageous configura-tions that diminished ohmic resistance between electrolyte and electrodes.It also increased the proton-conducting rate and improved the performance of SOFCs due to the reduction of membrane thickness and good contact between electrolyte and electrodes.The fabricated PEN cell generated electricity between 600℃ and 680℃ using H2S as fuel feed and air as oxidant.Maximum power densities 40 mW·cm^(-2) and 130 mW·cm^(-2) for the PEN configuration with a Mo-Ni-S-based composite anode,nano-composite electrolyte(Li_(2)SO_(4)+Al_(2)O_(3))film and a NiO-based composite cathode were achieved at 600℃ and 680℃,respectively.
