This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polyme...This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polymer electrolyte membrane) and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC (polymer electrolyte fuel cell). A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature (Treact). This study investigated the effects of flow rate, relative humidity and type of supply gas as well as Tini on the temperature distribution on reaction surface. The results obtained in 02 supply case show that, the temperature rise at the segments near the outlet of cell decreases with increasing Tini irrespective of relative humidity of supply gas (RH), while it is not seen in air supply case. Regarding the segments except near the outlet in 02 supply case, Treact - Tini increases with increasing Tini for 40% RH. The temperature distribution on reaction surface in 02 supply case is wider with increasing Tini as well as decreasing RH, though that in air supply case is relatively even.展开更多
Proton exchange membrane fuel cells(PEMFCs)suffer extreme CO poisoning even at PPM level(<10 ppm),owning to the preferential CO adsorption and the consequential blockage of the catalyst surface.Herein,however,we re...Proton exchange membrane fuel cells(PEMFCs)suffer extreme CO poisoning even at PPM level(<10 ppm),owning to the preferential CO adsorption and the consequential blockage of the catalyst surface.Herein,however,we report that CO itself can become an easily convertible fuel in PEMFC using atomically dispersed Rh catalysts(Rh-N-C).With CO to CO_(2) conversion initiates at 0 V,pure CO powered fuel cell attains unprecedented power density at 236 mW cm^(-2),with maximum CO turnover frequency(64.65 s^(-1),363 K)far exceeding any chemical or electrochemical catalysts reported.Moreover,this feature enables efficient CO selective removal from H_(2) gas stream through the PEMFC technique,with CO concentration reduced by one order of magnitude through running only one single cell,while simultaneously harvesting electricity.We attribute such catalytic behavior to the weak CO adsorption and the co-activation of H_(2)O due to the interplay between two adjacent Rh sites.展开更多
文摘This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polymer electrolyte membrane) and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC (polymer electrolyte fuel cell). A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature (Treact). This study investigated the effects of flow rate, relative humidity and type of supply gas as well as Tini on the temperature distribution on reaction surface. The results obtained in 02 supply case show that, the temperature rise at the segments near the outlet of cell decreases with increasing Tini irrespective of relative humidity of supply gas (RH), while it is not seen in air supply case. Regarding the segments except near the outlet in 02 supply case, Treact - Tini increases with increasing Tini for 40% RH. The temperature distribution on reaction surface in 02 supply case is wider with increasing Tini as well as decreasing RH, though that in air supply case is relatively even.
基金supported by the National Key Research and Development Program of China (2017YFB0102900)the National Natural Science Foundation of China (21875243, 21633008, 21673221, and U1601211)+3 种基金Jilin Provincial Science and Technology Development Program (20200201001JC, 20190201270JC, and 20180101030JC)supported by the High Performance Computing Center of Jilin University and Jilin ProvinceNetwork and Computing Center of Changchun Institute of Applied Chemistry, Chinese Academy of Sciencessupported by Linglu Instruments (Shanghai) Co., Ltd.
文摘Proton exchange membrane fuel cells(PEMFCs)suffer extreme CO poisoning even at PPM level(<10 ppm),owning to the preferential CO adsorption and the consequential blockage of the catalyst surface.Herein,however,we report that CO itself can become an easily convertible fuel in PEMFC using atomically dispersed Rh catalysts(Rh-N-C).With CO to CO_(2) conversion initiates at 0 V,pure CO powered fuel cell attains unprecedented power density at 236 mW cm^(-2),with maximum CO turnover frequency(64.65 s^(-1),363 K)far exceeding any chemical or electrochemical catalysts reported.Moreover,this feature enables efficient CO selective removal from H_(2) gas stream through the PEMFC technique,with CO concentration reduced by one order of magnitude through running only one single cell,while simultaneously harvesting electricity.We attribute such catalytic behavior to the weak CO adsorption and the co-activation of H_(2)O due to the interplay between two adjacent Rh sites.