Exploring single atom-based model catalysts to control the 2e- CO2 reduction path

Saswati Santra^a^,^b, Verena Streibel^a^,^b, Laura Wagner^a^,^b, Pan Ding^a^,^b, Guanda Zhou^a^,^b, Elise Sirotti^a^,^b, Ryan Kisslinger^a^,^b, Ningyan Cheng^c, Siyuan Zhang^c, Ian D. Sharp^a^,^b

^aWalter Schottky Institute, Technical University of Munich, Germany

^bPhysics Department, TUM School of Natural Sciences, Technical University of Munich, Germany

^cMax Planck Institute for Iron Research, Düsseldorf, Germany

Materials for Sustainable Development Conference (MATSUS)
Proceedings of MATSUS Fall 2023 Conference (MATSUSFall23)

#CO2X - Frontier developments in Electrochemical CO2 reduction and the utilization

Torremolinos, Spain, 2023 October 16th - 20th

Organizers: Alexander Bagger and Yu Katayama

Oral, Saswati Santra, presentation 139
DOI: https://doi.org/10.29363/nanoge.matsus.2023.139
Publication date: 18th July 2023

The CO₂ reduction reaction (CO2RR) has shown promise for producing C1-based feedstocks, including formic acid, CO, and syngas, under ambient conditions. A great challenge in this effort is to achieve control over the reaction path in order to define the product selectivity. In this work, we exploit the well-defined atomic structure and tunable coordination environment of Bi-based single atom catalysts (SACs)[1] embedded in carbon-nitrogen frameworks to show that the coordination environment of a single metallic species can be used to tune product selectivity. Bi is well-known to be an efficient CO2RR catalyst to produce formic acid,[2, 3] but has also recently been reported for CO generation.[4] While it has been hypothesised that this differing CO2RR product selectivity may arise from different Bi coordination environments, these different products stem from dissimilar catalytic systems. Here, we aim to test this hypothesis on the same catalyst system to exclude other influences on selectivity.

Using Bi SACs within a carbon-nitrogen framework, we find that the CO2RR selectivity can be tuned towards formic acid or syngas production by choosing tailored annealing treatments. Bi SACs anchored on commercially available carbon black were synthesized via a solution-based chemical method followed by inert atmosphere annealing. The single-atomic nature of Bi is confirmed by both scanning transmission electron microscopy and X-ray absorption spectroscopy. Low-temperature (300 °C) annealing of these samples results in oxygen-coordinated Bi SACs and promotes formic acid generation, while high-temperature annealing (800 °C) favours formation of nitrogen-coordinated Bi SACs and syngas production. Since the versatility of a single CO2RR catalyst system for producing two different major products has rarely been reported, our work opens up a new direction of tuning the CO2RR C1 product selectivity using SACs.

References:

[1] Yang, X.-F.;Wang, A.;Qiao, B.;Li, J.;Liu, J.; Zhang, T. Single-atom catalysts: a new frontier in heterogeneous catalysis. Accounts of chemical research 2013, 46, 1740-1748.

[2] Koh, J. H.;Won, D. H.;Eom, T.;Kim, N.-K.;Jung, K. D.;Kim, H.;Hwang, Y. J.; Min, B. K. Facile CO2 electro-reduction to formate via oxygen bidentate intermediate stabilized by high-index planes of Bi dendrite catalyst. Acs Catalysis 2017, 7, 5071-5077.

[3] Yang, X.;Chen, Y.;Qin, L.;Wu, X.;Wu, Y.;Yan, T.;Geng, Z.; Zeng, J. Boost selectivity of HCOO− using anchored Bi single atoms towards CO2 reduction. ChemSusChem 2020, 13, 6307-6311.

[4] Zhang, E.;Wang, T.;Yu, K.;Liu, J.;Chen, W.;Li, A.;Rong, H.;Lin, R.;Ji, S.; Zheng, X. Bismuth single atoms resulting from transformation of metal–organic frameworks and their use as electrocatalysts for CO2 reduction. Journal of the American Chemical Society 2019, 141, 16569-16573.

nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.

MATSUS

Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.

International Conference on Hybrid and Organic Photovoltaics

International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.

Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics

The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.

International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics

The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.