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    					Photocatalytic syngas synthesis from CO2 and H2O using ultrafine CeO2-decorated layered double hydroxide nanosheets under visible-light up to 600 nm  | 
  					 
  					  										
						Ling Tan, Kipkorir Peter, Jing Ren, Baoyang Du, Xiaojie Hao, Yufei Zhao( ), Yu-Fei Song( ) | 
					 
															
						| State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China | 
					 
										
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													     		                            						                            																	    Abstract  The rational design of photocatalyst that can effectively reduce CO2 under visible light (l>400 nm), and simultaneously precise control of the products syngas (CO/H2) ratio is highly desirable for the Fischer-Tropsch reaction. In this work, we synthesized a series of CeO2-decorated layered double hydroxides (LDHs, Ce-x) samples for photocatalytic CO2 reduction. It was found that the selectivity and productivity of CO and H2 from photoreduction of CO2 in conjunction with Ru-complex as photosensitizer performed an obvious “volcano-like” trend, with the highest point at Ce-0.15 and the CO/H2 ratio can be widely tunable from 1/7.7 to 1/1.3. Furthermore, compared with LDH, Ce-0.15 also drove photocatalytic CO2 to syngas under 600 nm irradiation. It implied that an optimum amount of CeO2 modifying LDH promoted the photoreduction of CO2 to syngas. This report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation. 
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															| Keywords 
																																																				visible light catalysis  
																		  																																				CO2 conversion  
																		  																																				layered double hydroxide  
																		  																																				rare earth elements  
																																			  
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																																Corresponding Author(s):
																Yufei Zhao,Yu-Fei Song   
																													     		
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																															Just Accepted Date: 04 June 2020  
																																														Online First Date: 30 July 2020   
																																														Issue Date: 12 January 2021
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														     															     		https://doi.org/10.1002/anie.201811545
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