High-efficiency direct methane conversion to oxygenates on a cerium dioxide nanowires supported rhodium single-atom catalyst

Abstract

Direct methane conversion (DMC) to high value-added products is of significant importance for the effective utilization of CH 4 to combat the energy crisis. However, there are ongoing challenges in DMC associated with the selective C−H activation of CH 4. The quest for highefficiency catalysts for this process is limited by the current drawbacks including poor activity and low selectivity. Here we show a cerium dioxide (CeO 2) nanowires supported rhodium (Rh) single-atom (SAs Rh-CeO 2 NWs) that can serve as a high-efficiency catalyst for DMC to oxygenates (i.e., CH 3 OH and CH 3 OOH) under mild conditions. Compared to Rh/CeO 2 nanowires (Rh clusters) prepared by a conventional wet-impregnation method, CeO 2 nanowires supported Rh single-atom exhibits 6.5 times higher of the oxygenates yield (1231.7 vs. 189.4 mmol g Rh −1 h −1), which largely outperforms that of the reported catalysts in the same class. This work demonstrates a highly efficient DMC process and promotes the research on Rh single-atom catalysts in heterogeneous catalysis.

Synthesis Strategies, Catalytic Applications, and Performance Regulation of Single‐Atom Catalysts

“…Besides the widely reported application in these fields described above, SACs have also attracted intensive research interest in both experimental investigations and theoretical calculations, [ 222–225 ] such as water–gas shift (WGS) reaction, [ 210–212,226–228 ] CO oxidation, [ 34,229–231 ] methane conversion, etc. [ 232–235 ]…”

A Review on Ceo2‐Based Electrocatalyst and Photocatalyst in Energy Conversion

“…Meanwhile, CeO 2 also plays as a good atomic catalyst support for Rh single atomic catalyst. [ 142 ] CeO 2 shows a good coupling effect with the anchoring Rh atoms to stabilize the surface atom, which also further optimizes the binding strength of CH 4 to achieve the oxidation process. In recent years, the theoretical investigation of CeO 2 is usually based on the transition metal modification.…”

Highly Active and Stable Palladium Catalysts Supported on Surface‐modified Ceria Nanowires for Lean Methane Combustion

“…The CeO 2 nanowires were synthesized by a hydrothermal method in term of previous report. [19] Lastly, the ceria surface was modified by triethoxy-n-octysilane (TEOOS) to produce organic silicon sheath around the nanowires in which the longchain alkyl groups were retained under reflux conditions. When ceria was modified by the TEOOS at 110°C, the alkoxy groups tend to hydrolysis and then attach on the ceria surface to assemble SiÀ OÀ Ce bonds.…”

“…Synthesis of CeO 2 nanowires (NWs): The preparation of the CeO 2 nanowires was in a typical method. [19] 60 mL CeCl 3 (2.5 mmol, Aladdin Industrial Corporation) aqueous solution and sodium oleate (1.5 mmol, Aladdin Industrial Corporation) were added into a 100 mL stainless-steel autoclave. After magnetically stirred for 0.5 h stirring at room temperature, 5 mL n-butylamine was sequentially added into the above solution mixture for another 0.5 h under stirring.…”