Portarapillo Maria, Landi Gianluca, Luciani Giuseppina, Imparato Claudio, Vitiello Giuseppe, Deorsola Fabio A, Aronne Antonio, Di Benedetto Almerinda
Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Univ. of Naples Federico II P.le Tecchio 80 80125 Naples Italy
Institute of Sciences and Technologies for Sustainable Energy and Mobility, CNR P.le Tecchio 80 80125 Naples Italy
RSC Adv. 2022 May 16;12(23):14645-14654. doi: 10.1039/d2ra01355j. eCollection 2022 May 12.
CeO slow redox kinetics as well as low oxygen exchange ability limit its application as a catalyst in solar thermochemical two-step cycles. In this study, CeZrO catalysts doped with potassium or transition metals (Cu, Mn, Fe), as well as co-doped materials were synthesized. Samples were investigated by X-ray diffraction (XRD), N sorption (BET), as well as by electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) to gain insight into surface and bulk features, which were connected to redox properties assessed both in a thermogravimetric (TG) balance and in a fixed bed reactor. Obtained results revealed that doping as well as co-doping with non-reducible K cations promoted the increase of both surface and bulk oxygen vacancies. Accordingly, K-doped and Fe-K co-doped materials show the best redox performances evidencing the highest reduction degree, the largest H amounts and the fastest kinetics, thus emerging as very interesting materials for solar thermochemical splitting cycles.
CeO缓慢的氧化还原动力学以及较低的氧交换能力限制了其作为太阳能热化学两步循环催化剂的应用。在本研究中，合成了掺杂钾或过渡金属（铜、锰、铁）的CeZrO催化剂以及共掺杂材料。通过X射线衍射（XRD）、N吸附（BET）以及电子顺磁共振（EPR）和X射线光电子能谱（XPS）对样品进行了研究，以深入了解表面和体相特征，这些特征与在热重（TG）天平及固定床反应器中评估的氧化还原性能相关。所得结果表明，用不可还原的K阳离子进行掺杂及共掺杂促进了表面和体相氧空位的增加。因此，K掺杂和Fe-K共掺杂材料表现出最佳的氧化还原性能，证明了最高的还原度、最大的H含量和最快的动力学，从而成为太阳能热化学分解循环中非常有吸引力的材料。
