Semiconductor/Covalent-Organic-Framework Z-Scheme Heterojunctions for Artificial Photosynthesis
Zhang, M (Zhang, Mi)[ 1 ] ; Lu, M (Lu, Meng)[ 1 ] ; Lang, ZL (Lang, Zhong-Ling)[ 2 ] ; Liu, J (Liu, Jiang)[ 1 ] ; Liu, M (Liu, Ming)[ 1 ] ; Chang, JN (Chang, Jia-Nan)[ 1 ] ; Li, LY (Li, Le-Yan)[ 1 ] ; Shang, LJ (Shang, Lin-Jie)[ 1 ] ; Wang, M (Wang, Min)[ 1 ] ; Li, SL (Li, Shun-Li)[ 1 ] ; Lan, YQ (Lan, Ya-Qian)[ 1 ]*（兰亚乾）
[ 1 ] Nanjing Normal Univ, Jiangsu Collaborat Innovat Ctr Biomed Funct Mat, Sch Chem & Mat Sci, 1 Wenyuan Rd, Nanjing 210023, Peoples R China
[ 2 ] Northeast Normal Univ, Fac Chem, Key Lab Polyoxometalate Sci, Minist Educ, Changchun 130000, Peoples R China
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION，202002,10.1002/anie.202000929
A strategy to covalently connect crystalline covalent organic frameworks (COFs) with semiconductors to create stable organic-inorganic Z-scheme heterojunctions for artificial photosynthesis is presented. A series of COF-semiconductor Z-scheme photocatalysts combining water-oxidation semiconductors (TiO2, Bi2WO6, and alpha-Fe2O3) with CO2 reduction COFs (COF-316/318) was synthesized and exhibited high photocatalytic CO2-to-CO conversion efficiencies (up to 69.67 mu mol g(-1) h(-1)), with H2O as the electron donor in the gas-solid CO2 reduction, without additional photosensitizers and sacrificial agents. This is the first report of covalently bonded COF/inorganic-semiconductor systems utilizing the Z-scheme applied for artificial photosynthesis. Experiments and calculations confirmed efficient semiconductor-to-COF electron transfer by covalent coupling, resulting in electron accumulation in the cyano/pyridine moieties of the COF for CO2 reduction and holes in the semiconductor for H2O oxidation, thus mimicking natural photosynthesis.