School of Chemical Engineering, The University of Queensland , Brisbane, Queensland 4072, Australia.
Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry & Chemical Engineering, Nanjing Tech University , No. 5 Xin Mofan Road, Nanjing 210009, Jiangsu, P.R. China.
ACS Appl Mater Interfaces. 2017 Oct 4;9(39):33758-33765. doi: 10.1021/acsami.7b07938. Epub 2017 Sep 20.
Performance degradation caused by carbon deposition substantially restricts the development of direct methane solid oxide fuel cells (SOFCs). Here, an internal reforming layer composed of Ni supported on proton conducting La-doped ceria, such as LaCeO (LDC) and LaSmCeO (LSDC) is applied over conventional Ni-CeSmO (SDC) anodes for direct methane SOFCs. The proton conducting layer can adsorb water for internal reforming thus significantly improving the performance of the direct methane SOFCs. In situ Raman and FTIR results confirm the water adsorption capacity of LDC and LSDC. They also exhibit excellent phase stability in wet CO at 650 °C for 10 h, which ensures that the additional catalyst layer maintains structure stability during the internal reforming. In wet methane at 650 °C, the peak power density of the conventional cell is only 580 ± 20 mW cm, and increases to 699 ± 20 and 639 ± 20 mW cm with the addition of Ni-LDC and -LSDC layers, respectively. For the stability test in wet methane at 650 °C and 0.2 A cm, the voltage of the conventional cell starts to drop dramatically in 10 h, while the Ni-LDC and -LSDC catalyst layers operate stably in 26 h under the identical conditions. These catalyst layers even show comparable stability in dry and wet methane in 26 h, but for longer operation, the wet methane is still preferred for maintaining the stability of the cell.
积碳引起的性能下降极大地限制了直接甲烷固体氧化物燃料电池（SOFC）的发展。在此，在传统的 Ni-CeSmO（SDC）阳极上应用了由质子导体 La 掺杂的 CeO2 负载的 Ni 组成的内部重整层，例如 LaCeO（LDC）和 LaSmCeO（LSDC），用于直接甲烷 SOFC。质子导体层可以吸附水进行内部重整，从而显著提高直接甲烷 SOFC 的性能。原位拉曼和 FTIR 结果证实了 LDC 和 LSDC 的水吸附能力。它们在 650°C 的湿 CO 中也表现出优异的相稳定性，在 10 小时内，这确保了附加的催化剂层在内部重整过程中保持结构稳定性。在 650°C 的湿甲烷中，传统电池的峰值功率密度仅为 580±20 mW cm，而添加 Ni-LDC 和 -LSDC 层后，分别增加到 699±20 和 639±20 mW cm。在 650°C 和 0.2 A cm 的湿甲烷稳定性测试中，传统电池的电压在 10 小时内开始急剧下降，而 Ni-LDC 和 -LSDC 催化剂层在相同条件下稳定运行 26 小时。这些催化剂层在 26 小时的干甲烷和湿甲烷中表现出相当的稳定性，但对于更长的运行时间，仍需要湿甲烷来维持电池的稳定性。
