scholarly journals Investigating the Origin of Enhanced C2+ Selectivity in Oxide-/Hydroxide-Derived Copper Electrodes during CO2 Electroreduction

2020 ◽  
Vol 142 (9) ◽  
pp. 4213-4222 ◽  
Author(s):  
Qiong Lei ◽  
Hui Zhu ◽  
Kepeng Song ◽  
Nini Wei ◽  
Lingmei Liu ◽  
...  
ACS Catalysis ◽  
2016 ◽  
Vol 6 (4) ◽  
pp. 2382-2392 ◽  
Author(s):  
Marta C. Figueiredo ◽  
Isis Ledezma-Yanez ◽  
Marc T. M. Koper

2020 ◽  
Author(s):  
Jennifer A. Rudd ◽  
Ewa Kazimierska ◽  
Louise B. Hamdy ◽  
Odin Bain ◽  
Sunyhik Ahn ◽  
...  

The utilization of carbon dioxide is a major incentive for the growing field of carbon capture. Carbon dioxide could be an abundant building block to generate higher value products. Herein, we describe the use of porous copper electrodes to catalyze the reduction of carbon dioxide into higher value products such as ethylene, ethanol and, notably, propanol. For <i>n</i>-propanol production, faradaic efficiencies reach 4.93% at -0.83 V <i>vs</i> RHE, with a geometric partial current density of -1.85 mA/cm<sup>2</sup>. We have documented the performance of the catalyst in both pristine and urea-modified foams pre- and post-electrolysis. Before electrolysis, the copper electrode consisted of a mixture of cuboctahedra and dendrites. After 35-minute electrolysis, the cuboctahedra and dendrites have undergone structural rearrangement. Changes in the interaction of urea with the catalyst surface have also been observed. These transformations were characterized <i>ex-situ</i> using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. We found that alterations in the morphology, crystallinity, and surface composition of the catalyst led to the deactivation of the copper foams.


Author(s):  
Kailun Yang ◽  
Recep Kas ◽  
Wilson A. Smith

<p>This study evaluated the performance of the commonly used strong buffer electrolytes, i.e. phosphate buffers, during CO<sub>2</sub> electroreduction in neutral pH conditions by using in-situ surface enhanced infrared absorption spectroscopy (SEIRAS). Unfortunately, the buffers break down a lot faster than anticipated which has serious implications on many studies in the literature such as selectivity and kinetic analysis of the electrocatalysts. Increasing electrolyte concentration, surprisingly, did not extend the potential window of the phosphate buffers due to dramatic increase in hydrogen evolution reaction. Even high concentration phosphate buffers (1 M) break down within the potentials (-1 V vs RHE) where hydrocarbons are formed on copper electrodes. We have extended the discussion to high surface area electrodes by evaluating electrodes composed of copper nanowires. We would like highlight that it is not possible to cope with high local current densities on these high surface area electrodes by using high buffer capacity solutions and the CO<sub>2</sub> electrocatalysts are needed to be evaluated by casting thin nanoparticle films onto inert substrates as commonly employed in fuel cell reactions and up to now scarcely employed in CO<sub>2</sub> electroreduction. In addition, we underscore that normalization of the electrocatalytic activity to the electrochemical active surface area is not the ultimate solution due to concentration gradient along the catalyst layer.This will “underestimate” the activity of high surface electrocatalyst and the degree of underestimation will depend on the thickness, porosity and morphology of the catalyst layer. </p> <p> </p>


2020 ◽  
Vol 4 (7) ◽  
pp. 3726-3731
Author(s):  
Fenghui Ye ◽  
Jinghui Gao ◽  
Yilin Chen ◽  
Yunming Fang

Electroreduction of CO2 into value-added products is a promising technique in which the structure of the catalyst plays a crucial role.


Author(s):  
Junmin Yan ◽  
Yan-Xin Duan ◽  
Zhen Yu ◽  
Qing Jiang ◽  
Yi-Tong Zhou ◽  
...  
Keyword(s):  

ACS Catalysis ◽  
2021 ◽  
pp. 4456-4463
Author(s):  
Pranit Iyengar ◽  
Manuel J. Kolb ◽  
James R. Pankhurst ◽  
Federico Calle-Vallejo ◽  
Raffaella Buonsanti
Keyword(s):  

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