Saravanan Praveen Kumar, Bhalothia Dinesh, Huang Guo-Heng, Beniwal Amisha, Cheng Mingxing, Chao Yu-Chieh, Lin Ming-Wei, Chen Po-Chun, Chen Tsan-Yao
Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, Taipei 10608, Taiwan.
Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan.
Nanomaterials (Basel). 2023 Jun 5;13(11):1801. doi: 10.3390/nano13111801.
The catalytic conversion of CO into valuable commodities has the potential to balance ongoing energy and environmental issues. To this end, the reverse water-gas shift (RWGS) reaction is a key process that converts CO into CO for various industrial processes. However, the competitive CO methanation reaction severely limits the CO production yield; therefore, a highly CO-selective catalyst is needed. To address this issue, we have developed a bimetallic nanocatalyst comprising Pd nanoparticles on the cobalt oxide support (denoted as CoPd) via a wet chemical reduction method. Furthermore, the as-prepared CoPd nanocatalyst was exposed to sub-millisecond laser irradiation with per-pulse energies of 1 mJ (denoted as CoPd-1) and 10 mJ (denoted as CoPd-10) for a fixed duration of 10 s to optimize the catalytic activity and selectivity. For the optimum case, the CoPd-10 nanocatalyst exhibited the highest CO production yield of ∼1667 μmol g, with a CO selectivity of ∼88% at a temperature of 573 K, which is a 41% improvement over pristine CoPd (~976 μmol g). The in-depth analysis of structural characterizations along with gas chromatography (GC) and electrochemical analysis suggested that such a high catalytic activity and selectivity of the CoPd-10 nanocatalyst originated from the sub-millisecond laser-irradiation-assisted facile surface restructure of cobalt oxide supported Pd nanoparticles, where atomic CoOx species were observed in the defect sites of the Pd nanoparticles. Such an atomic manipulation led to the formation of heteroatomic reaction sites, where atomic CoOx species and adjacent Pd domains, respectively, promoted the CO activation and H splitting steps. In addition, the cobalt oxide support helped to donate electrons to Pd, thereby enhancing its ability of H splitting. These results provide a strong foundation to use sub-millisecond laser irradiation for catalytic applications.
将一氧化碳催化转化为有价值的产品，有潜力平衡当前的能源和环境问题。为此，逆水煤气变换（RWGS）反应是将一氧化碳转化为用于各种工业过程的一氧化碳的关键过程。然而，竞争性的一氧化碳甲烷化反应严重限制了一氧化碳的产率；因此，需要一种高一氧化碳选择性的催化剂。为了解决这个问题，我们通过湿化学还原法制备了一种在氧化钴载体上负载钯纳米颗粒的双金属纳米催化剂（记为CoPd）。此外，将制备好的CoPd纳米催化剂在固定时长10秒内，分别用每脉冲能量为1 mJ（记为CoPd-1）和10 mJ（记为CoPd-10）的亚毫秒激光照射，以优化其催化活性和选择性。在最佳情况下，CoPd-10纳米催化剂在573 K温度下表现出最高的一氧化碳产率，约为1667 μmol g，一氧化碳选择性约为88%，相较于原始的CoPd（约976 μmol g）提高了41%。结合气相色谱（GC）和电化学分析对结构表征进行的深入分析表明，CoPd-10纳米催化剂如此高的催化活性和选择性源于亚毫秒激光照射辅助下，氧化钴负载钯纳米颗粒表面的快速重构，在钯纳米颗粒的缺陷位点观察到了原子CoOx物种。这种原子操控导致了杂原子反应位点的形成，其中原子CoOx物种和相邻的钯域分别促进了一氧化碳活化和氢裂解步骤。此外，氧化钴载体有助于向钯提供电子，从而增强其氢裂解能力。这些结果为亚毫秒激光照射在催化应用中的使用提供了坚实的基础。
