Hossain Akbar, Ghorai Kalyan, Bhunia Trilochan, Llorca Jordi, Vasundhara M, Bera Parthasarathi, Bhaskaran Aathira, Roy Sounak, Seikh Md Motin, Gayen Arup
Physical Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
Institute of Energy Technologies, Department of Chemical Engineering and Barcelona Research Center in Multiscale Science and Engineering, Universitat Politècnica de Catalunya, EEBE, 08019 Barcelona, Spain.
Phys Chem Chem Phys. 2024 Oct 23;26(41):26603-26621. doi: 10.1039/d4cp02252a.
Dry reforming of methane (DRM) was extensively studied on Cu-doped LaNiO catalysts. The main findings of this work are as follows: (i) thermal switching of the catalyst phase between the parent perovskite and molecular-level nanocomposite of individual components formed during DRM, (ii) reusability of the catalyst with enhanced activity, and (iii) regeneration of the catalyst phase at a lower temperature than that required for the formation of the parent perovskite. The present investigation provides an extensive analysis and understanding of the DRM reaction using Cu-doped LaNiO compared to the result reported by Moradi , (, 2012, , 797-801) and hence provides new insights into its catalytic activity. Phase-pure LaNiCuO catalysts, specifically LaNiCuO, exhibited high catalytic activity towards the DRM reaction (97% CH and 99% CO conversion with an H/CO ratio of ∼1.4-0.9). Remarkably, although the initial perovskite phase primarily decomposed into its component phases after DRM, its catalytic activity was barely affected and maintained even after 100 h. The regeneration of the initial perovskite from the disintegrated binary phases annealing at temperatures even lower than the synthesis temperature together with the amazing retention of activity was very intriguing. The parallel activity of the pristine perovskite and its degraded binary mixtures makes it difficult to identify the actual components responsible for the DRM activity. Accordingly, we have explained the sustained activity of the degraded perovskite catalyst in the context of nanocomposite formation at the molecular level in the reforming atmosphere with the availability of Ni and NiO, as revealed by the thoroughly characterized samples in the as-prepared, aged, and regenerated forms.
对掺杂铜的LaNiO催化剂上的甲烷干重整（DRM）进行了广泛研究。这项工作的主要发现如下：（i）催化剂相在母体钙钛矿和DRM过程中形成的各组分的分子级纳米复合材料之间的热转换；（ii）催化剂具有可重复使用性且活性增强；（iii）催化剂相在比形成母体钙钛矿所需温度更低的温度下再生。与Moradi（2012年，第797 - 801页）报道的结果相比，本研究对使用掺杂铜的LaNiO的DRM反应进行了广泛分析和理解，从而为其催化活性提供了新的见解。纯相LaNiCuO催化剂，特别是LaNiCuO，对DRM反应表现出高催化活性（CH转化率为97%，CO转化率为99%，H/CO比约为1.4 - 0.9）。值得注意的是，尽管初始钙钛矿相在DRM后主要分解为其组成相，但其催化活性几乎未受影响，即使在100小时后仍能保持。从分解的二元相在甚至低于合成温度的温度下退火再生初始钙钛矿以及令人惊讶的活性保留非常引人关注。原始钙钛矿及其降解二元混合物的平行活性使得难以确定负责DRM活性的实际成分。因此，我们根据在重整气氛中分子水平上纳米复合材料的形成情况，结合所制备、老化和再生形式的充分表征样品所揭示的Ni和NiO的可用性，解释了降解钙钛矿催化剂的持续活性。
