Two-dimensional metal-organic framework electrocatalyst

• Main Author: Solco Samantha Faye Duran
• Other Authors: Huang Yizhong
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2020
• Subjects: Engineering::Materials::Nanostructured materials
• Online Access: https://hdl.handle.net/10356/138804
• Institution: Nanyang Technological University

Metal-organic-frameworks (MOFs) have been of much interest as potential effective electrocatalysts for OER due to their high effective surface area and tuneable structures. They are advantageous over traditional catalysts as the many variations of structures of the MOFs give room for adaptation of the application according to various needs. One of the pathways it can go is through nano scaling. In this project, ultrathin metal organic-framework nanosheets (UMOFNs) were successfully synthesized. Monometallic Cu UMOFNs and Co UMOFNs were compared against bimetallic Cu-Co UMOFNs of various ratios such as 1:1, 1:2 and 2:1. FESEM imaging confirmed that their morphologies displayed a flake-like structure of diameters 100nm and smaller. The electrocatalytic performance of the synthesized MOFs was studied by comparing data in the LSV, Nyquist and Tafel plots. As predicted, the bimetallic UMOFNs performed better than the monometallic MOFs with 339mV as the lowest overpotential achieved. Furthermore, increasing the percentage of cobalt, which has shown to be a more effective catalyst than copper in the synthesis of the bimetallic MOFs also lead to better performance. However, there was no significant improvement in the kinetics of the reaction as observed from the Tafel plots which displayed similar valued slopes. It is only conclusive that using the mentioned mode of synthesis, the electrocatalytic capability of Cu-Co MOFs can be improved thermodynamically through a decrease in overpotential required to obtain a current density of 10mAcm-2. In addition, further work can be done to investigate the stability of the Cu-Co UMOFN as well as the minimum overpotential it can achieve given the observed trend.