TY - JOUR A1 - Pilar Yeste, Maria A1 - Carlos Hernandez-Garrido, Juan A1 - Kumke, Michael Uwe A1 - Alvarado, Sarah A1 - Cauqui, Miguel Angel A1 - Juan Calvino, Jose A1 - Primus, Philipp-Alexander T1 - Low-temperature growth of reactive pyrochlore nanostructures on Zirconia-supported ceria BT - implications for improved catalytic behavior JF - ACS applied nano materials N2 - The use of a catalyst support for the design of nanoscale heterogeneous catalysts based on cerium oxide offers vast possibilities for future catalyst development, particularly with regard to an increased focus on the use of renewable biogas and an emerging hydrogen economy. In this study, zirconia-supported ceria catalysts were synthesized, activated by using different thermochemical treatments, and characterized by way of temperature-programmed reduction (TPR), oxygen storage capacity, Xray diffraction, electron microscopy, and luminescence spectroscopy using Eu3+ as a spectroscopic probe. Through reduction-oxidation pretreatment routines, reactive pyrochlore structures were created at temperatures as low as 600 degrees C and identified through TPR and electron microscopy experiments. A structural relationship and alignment of the crystal planes is revealed in high-resolution scanning transmission electron microscopy experiments through the digital diffraction patterns. Low-temperature pretreatment induces the formation of reactive pyrochlore domains under retention of the surface area of the catalyst system, and no further morphological changes are detected. Furthermore, the formation of pyrochlore domains achieved through severe reduction and mild reoxidation (SRMO) treatments is reversible. Over multiple alternating SRMO and severe reduction and severe reoxidation (SRSO) treatments, europium spectroscopy and TPR results indicate that pyrochlore structures are recreated over consecutive treatments, whenever the mild oxidation step at 500 degrees C is the last treatment (SRMO, SRMO-SRSO-SRMO, etc.). KW - pyrochlore KW - nanocomposite KW - ceria KW - zirconia KW - supported catalyst KW - oxygen KW - storage capacity Y1 - 2022 U6 - https://doi.org/10.1021/acsanm.2c00416 SN - 2574-0970 VL - 5 IS - 5 SP - 6316 EP - 6326 PB - American Chemical Society CY - Washington ER - TY - GEN A1 - Kühn, Michael A1 - Kempka, Thomas A1 - de Lucia, Marco A1 - Scheck-Wenderoth, Magdalena T1 - Dissolved CO2 storage in geological formations with low pressure, low risk and large capacities T2 - Energy procedia N2 - Geological CO2 storage is a mitigation technology to reduce CO2 emissions from fossil fuel combustion. However, major concerns are the pressure increase and saltwater displacement in the mainly targeted deep groundwater aquifers due to injection of supercritical CO2. The suggested solution is storage of CO2 exclusively in the dissolved state. In our exemplary regional case study of the North East German Basin based on a highly resolved temperature and pressure distribution model and a newly developed reactive transport coupling, we have quantified that 4.7 Gt of CO2 can be stored in solution compared to 1.5 Gt in the supercritical state. KW - carbon dioxide KW - dissolved KW - storage capacity KW - numerical simulation KW - saline aquifer KW - Buntsandstein Y1 - 2017 U6 - https://doi.org/10.1016/j.egypro.2017.03.1607 SN - 1876-6102 VL - 114 SP - 4722 EP - 4727 PB - Elsevier CY - Amsterdam ER -