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Prof. Fabrizio Pirri
Theses at Politecnico
Electrochemical CO2 conversion to value-added products in acidic electrolyte
keywords ACID ELECTROLYTE, CO2 REDUCTION, ELECTROCATALYSIS
Reference persons JUQIN ZENG
Research Groups Prof. Fabrizio Pirri
Thesis type MASTER'S DEGREE
Description A carbon cycle with carbon neutrality or net-zero CO2 emissions is an essential practice to achieve sustainable development of human societies. Among many strategies, electrochemical conversion of CO2 into valuable chemicals and fuels has attracted tremendous interest, since it possesses advantageous properties such as the utilization of green electrolytes, the high tunability of products and the potential implementation of electricity from renewable energy. However, the CO2 reduction reaction (CO2RR) faces many challenges, one of which is the carbonate formation in alkaline and neutral electrolytes, leading to low CO2 utilization efficiency and poor durability. Furthermore, the products as formate, acetate and ethanol move through the anion exchange membrane by migration, diffusion and electro-osmotic drag, resulting in product loss [https://doi.org/10.1038/s41893-022-00879-8]. CO2RR under acidic conditions is expected to address these challenges of neutral and alkaline electrolyte systems. A high proton concentration in the electrolyte and the use of Nafion membrane as the separator are expected to minimize carbonate formation and liquid product crossover, and increase the efficiency of process [https://doi.org/10.1038/s41929-022-00788-1]. However, a higher proton concentration usually leads to higher activity for competitive hydrogen evolution reaction (HER). Hence, the careful choice of catalytic materials should be taken into consideration. Silver (Ag) and bismuth (Bi) electrodes have been demonstrated to have excellent selectivity for the CO2RR in alkaline and neutral electrolytes in our lab [https://doi.org/10.1021/acsaem.2c02143; https://doi.org/10.3390/cryst11040363]. In this project, we propose the following scientific activities: 1) prepare Ag and Bi electrodes with our well-established methods; 2) characterize the morphology and chemical composition of the materials through XRD, EDX, FESEM, XPS and so on; 3) perform CO2 electrolysis on the electrodes in acidic conditions; 4) tune the pH range and cell configuration in order reach high selectivity and activity, and particularly enhanced durability.
Deadline 06/05/2025
PROPONI LA TUA CANDIDATURA