Recently, Professor Zhao Guohua’s academic team published its latest research results on "A CO2 adsorption-enhanced semiconductor / metal-complex hybrid photoelectrocatalytic interface for efficient formate production" in Energy & Environmental Science. (2016, DOI: 10.1039 / C6EE00968A, Journal Impact Factor: 25.427). This research has established a new biomimetic interface system in selective photocatalytic selective CO2 reduction, which can convert CO 2 into formic acid efficiently and selectively. This is an important step for people to use CO2 with low energy consumption and resource utilization. Dr. Huang Xiaofeng and Shen Qi, PhD students of the research group respectively, are the first and second authors of the paper.

The traditional consumption of oil and fossil energy has caused the greenhouse effect and the energy shortage, which is the great challenge human beings are facing at present. Under this circumstances, utilization of CO2 in low energy consumption, efficiently and selectively conversion of liquid fuel to achieve the CO2 "reverse combustion" is increasingly getting concern by the national research workers. Natural green plant photosynthesis by Rubisco and other key enzyme catalysis, mildly convert CO2 to glucose. Inspired by this, bionic photo-catalysis has led to the possibility of efficient CO2 conversion.

In recent years, the research group has been committed to CO2 biomimetic photosynthesis study. Based on the early discovery that high crystal surface of the metal cobalt oxide Co3O4 material has a good photoelectric catalytic reduction of CO2 and efficiency and efficiency of the CO2 conversion study (Environ. Sci Catal. B: Environ. 2017, 201, 70-76.), the study cleverly increased the amount of H Crystal surface of the Co3O4 excellent photoelectrocatalyst, the specific structure of the metal ruthenium complex bionic enzyme assembled in high specific surface area of porous carbon aerogels surface to build CO2 artificial photosynthesis of bionic structure reaction interface.

Here’s the abstract of the research: In photoelectrochemical CO2 conversion, the concentration of fixed CO2 on the photocathode surface is of primary concern. Herein, a CO2 adsorption-enhanced semiconductor/metal-complex hybrid photoelectrocatalytic interface was established by utilizing a carbon aerogel as the CO2 fixation substrate. In CO2 reduction photoelectrocatalysis, Co3O4 was employed as the light harvester, and Ru(bpy)2dppz was utilized as the electron transfer mediator and CO2 activator. The CO2 surface concentration exhibited a 380-fold increase on this hybrid interface than that on Co3O4/FTO. The CO2 conversion to formate occurred at an onset potential of 0.45 V (vs. normal hydrogen electrode, NHE) under photoelectrochemical conditions, 160 mV more positive than its thermodynamic redox potential. At an applied potential of 0.60 V (vs. NHE), the selectivity of the formate yield reached 99.95%, with a production rate of approximately 110 mmol cm2 h1 and a Faradaic efficiency of 86%. Such a conversion has an electron transfer rate of 2.94 103 cm s1 . The CO2 conversion to formate was confirmed to be an instantaneous proton-coupled electron transfer process, originating from the rapid photoelectrochemical activation of bpy and dppz in Ru(bpy)2dppz as well as the synergic effect of the promoted CO2 adsorption and the applied molecular catalysis.