Synergistic Integration of Zr-MOF (UiO-66) and Bi Electrocatalysts for Enhanced CO2 Conversion to Formate

• DOI: 10.1149/ma2023-02472382mtgabs
• Publication Date: 2024-02-08T20:00:43Z
• Authors: Jun Tae Song; Yuta Takaoka; Atsushi Takagaki; Motonori Watanabe; Tatsumi Ishihara

The utilization of renewable energy-driven CO 2 conversion technology has garnered considerable attention as a potential remedy for both the energy crisis and climate change. Among various methods, electrocatalytic reduction reaction (CO RR) received particular focus due to its mild conditions ability produce valuable products. Specifically, formic acid holds great promise electrolysis storage transportation, well commercial viability indicated by techno-economic assessments. Bi, In, Sn are several metal catalysts that have been reported production, with Bi demonstrating favorable properties in terms cost-effectiveness selective production acid. However, despite efforts enhance intrinsic catalytic activity through methods such nanostructuring alloying, it yet achieve desired level performance. In light recent findings Nam et al. on metal-organic framework (MOF) regulate intermediates Ag catalyst, resulting higher we draw inspiration from MOF's versatility demonstrate successful coupling UiO-66, Zr-MOF, rates thus increase [1]. We synthesized MOF materials, UiO-66 NH -functionalized (UiO-66-NH ), deposited structures using NaBH4 method, Bi/UiO-66 Bi/UiO-66-NH samples. To compare activity, also particle samples same method (Bi). Prior examination, all electrocatalysts were pre-treated 1.0 M KOH solution 5 minutes, then was performed flow-cell reactor. samples, demonstrated excellent properties, exhibiting about times current density (-220 mA/cm ) at an applied -0.7 V vs. reversible hydrogen electrode (RHE) than alone (-44 identical electrochemically active surface area (ECSA) On other hand, showed almost ECSA-normalized compared Bi/UiO-66, indicating negligible effect functionalization RR. Nevertheless, is evident Zr-MOF (UiO-66) beneficial increasing rate metallic catalyst. comprehend reason behind superior exhibited sample, conducted characterizations, SEM, TEM, FTIR, Raman, XPS. Our results revealed structural evolution occurs formation carbonate-coordinated Zr-hydroxide during electrolysis, contributing high density. Moreover, disappearance carbonate-relevant peak C 1s XPS analysis after decline suggests carbonate species formed site, which captured form molecules, play crucial role efficient capture conversion. These suggest can be used efficiency. [1] al., J. Am. Chem. Soc. 2020, 142, 51, 21513–21521.