Gallium based nano-catalysts for electrochemical CO2 reduction reaction

Thumbnail Image

Files

master_You_Haoxuan_2024.pdf (3.9 MB)

URL

Journal Title

Journal ISSN

Volume Title

School of Chemical Engineering | Master's thesis
Unless otherwise stated, all rights belong to the author. You may download, display and print this publication for Your own personal use. Commercial use is prohibited.

Authors

Date

2024-10-30

Department

Major/Subject

Functional Materials for Global Challenges

Mcode

Degree programme

Master's Programme in Advanced Materials for Innovation and Sustainability

Language

en

Pages

39

Series

Abstract

Organic chemicals rely heavily on natural gas as their primary raw material. The supply chain for natural gas faces challenges due to the uneven global distribution, which makes its market stability dependent on the volatile nature of global politics. Despite nature’s gas’s temporary market supremacy, electrochemical carbon dioxide reduction (CO2RR) offers a vital contingency plan which converts carbon dioxide (CO2) to valuable organic chemicals. As a strategic technology reserve, CO2RR can help mitigate risks associated with the geopolitical and market instability of natural gas. Catalysts play a key role in the CO2RR process, influencing both the rate of the reaction and the selectivity for desired products. Liquid metal catalysts based on gallium (Ga) have been shown to be promising materials for CO2RR. The intrinsic flexibility of liquid metal catalysts enhances the rebuilding of active sites and optimizes surface absorption for CO2. However, the low conductivity oxide layer on Ga nanoparticles (NPs) limits their catalytic performance. This thesis aims to optimize Ga-based NPs for CO2RR, focusing on selectivity and activity. The integration of carbon black NPs and Nafion into Ga NPs substantially enhanced the overall conductivity of the Ga NPs external layers. This modification demonstrated a notable improvement in carbon monoxide (CO) selectivity, achieving a CO Faradaic efficiency (CO FE) of 55% during one hour of CO2RR at -0.7 V vs. RHE in the H-cell. Ga NPs coalesced up to six times their original diameter after the reaction, demonstrating their liquid-like properties. In addition, the synergistic effect of bimetallic was studied by introducing silver (Ag) into Ga to form intermetallic Ag3Ga NPs.

Description

Supervisor

Elbahri, Mady

Thesis advisor

Buonsanti, Raffaella
Boulanger, Coline

Keywords

catalysts, liquid metal, electrodes, electrochemical CO2 reduction reaction, colloid chemistry, CO synthesis

Other note

Citation

Permanent link to this item

https://urn.fi/URN:NBN:fi:aalto-202412117731

Collections

[dipl] Kemian tekniikan korkeakoulu / CHEM