Control of evolution of porous copper-based metal-organic materials for electroreduction of CO 2 to multi-carbon products.
Lili LiLutong ShanAlena M ShevelevaMeng HeYujie MaYiqi ZhouMarek NikielLaura Lopez-OdriozolaLouise S NatrajanEric J L McInnesMartin SchröderSihai YangFloriana TunaPublished in: Materials advances (2023)
Electrochemcial reduction of CO 2 to multi-carbon (C 2+ ) products is an important but challenging task. Here, we report the control of structural evolution of two porous Cu(ii)-based materials (HKUST-1 and CuMOP, MOP = metal-organic polyhedra) under electrochemical conditions by adsorption of 7,7,8,8-tetracyanoquinodimethane (TNCQ) as an additional electron acceptor. The formation of Cu(i) and Cu(0) species during the structural evolution has been confirmed and analysed by powder X-ray diffraction, and by EPR, Raman, XPS, IR and UV-vis spectroscopies. An electrode decorated with evolved TCNQ@CuMOP shows a selectivity of 68% for C 2+ products with a total current density of 268 mA cm -2 and faradaic efficiency of 37% for electrochemcial reduction of CO 2 in 1 M aqueous KOH electrolyte at -2.27 V vs. RHE (reversible hydrogen electrode). In situ electron paramagnetic resonance spectroscopy reveals the presence of carbon-centred radicals as key reaction intermediates. This study demonstrates the positive impact of additional electron acceptors on the structural evolution of Cu(ii)-based porous materials to promote the electroreduction of CO 2 to C 2+ products.
Keyphrases
- metal organic framework
- aqueous solution
- solar cells
- ionic liquid
- electron microscopy
- high resolution
- highly efficient
- solid state
- electron transfer
- energy transfer
- gold nanoparticles
- computed tomography
- single molecule
- carbon nanotubes
- crystal structure
- tissue engineering
- water soluble
- visible light
- oxide nanoparticles