Air-synth Scientific Literature / Methodology Review

Below are published scientific papers that can help introduce the science and methodology behind Air-Synth. See the abstracts for key points from the papers.

  1. High-Selectivity Electrochemical Conversion of CO2 to Ethanol using a Copper Nanoparticle/N-Doped Graphene Electrode (Sci-Hub | High-Selectivity Electrochemical Conversion of CO2to Ethanol using a Copper Nanoparticle/N-Doped Graphene Electrode. ChemistrySelect, 1(19), 6055–6061 | 10.1002/slct.201601169)

Abstract: Though carbon dioxide is a waste product of combustion, it can also be a potential feedstock for the production of fine and commodity organic chemicals, provided that an efficient means to convert it to useful organic synthons can be developed. Herein we report a common element, nanostructured catalyst for the direct electrochemical conversion of CO2 to ethanol with high Faradaic efficiency (63 % at 1.2 V vs RHE) and high selectivity (84 %) that operates in water and at ambient temperature and pressure. Lacking noble metals or other rare or expensive materials, the catalyst is comprised of Cu nanoparticles on a highly textured, N-doped carbon nanospike film. Electrochemical analysis and density functional theory (DFT) calculations suggest a preliminary mechanism in which active sites on the Cu nanoparticles and the carbon nanospikes work in tandem to control the electrochemical reduction of carbon monoxide dimer to alcohol.

  1. New insights into the electrochemical reduction of carbon dioxide on metallic
    copper surfaces (Sci-Hub | New insights into the electrochemical reduction of carbon dioxide on metallic copper surfaces. Energy & Environmental Science, 5(5), 7050 | 10.1039/c2ee21234j)

Abstract: We report new insights into the electrochemical reduction of CO2 on a metallic copper surface, enabled by the development of an experimental methodology with unprecedented sensitivity for the identification and quantification of CO2 electroreduction products. This involves a custom electrochemical cell designed to maximize product concentrations coupled to gas chromatography and nuclear magnetic resonance for the identification and quantification of gas and liquid products, respectively. We studied copper across a range of potentials and observed a total of 16 different CO2 reduction products, five of which are reported here for the first time, thus providing the most complete view of the reaction chemistry reported to date. Taking into account the chemical identities of the wide range of C 1–C 3 products generated and the potential-dependence of their turnover frequencies, mechanistic information is deduced. We discuss a scheme for the formation of multicarbon products involving enol-like surface intermediates as a possible pathway, accounting for the observed selectivity for eleven distinct C(2+) oxygenated products including aldehydes, ketones, alcohols, and carboxylic acids.

  1. Electrocatalytic Reduction of CO2 to Ethanol at Close to Theoretical Potential via Engineering Abundant Electron-Donating Cuδ+ Species (https://onlinelibrary.wiley.com/doi/10.1002/anie.202205909) (access is a bit tougher with this link)

Abstract: Electrochemical CO2 reduction to liquid multi-carbon alcohols provides a promising way for intermittent renewable energy reservation and greenhouse effect mitigation. Cuδ+ (0<δ<1) species on Cu-based electrocatalysts can produce ethanol, but the in situ formed Cuδ+ is insufficient and easily reduced to Cu0. Here a Cu2S1−x catalyst with abundant Cuδ+ (0<δ<1) species is designedly synthesized and exhibited an ultra-low over-potential of 0.19 V for ethanol production. The catalyst not only delivers an outstanding ethanol selectivity of 86.9 % and a Faradaic efficiency of 73.3 % but also provides a long-term stability of Cuδ+, gaining an economic profit based on techno-economic analysis. The calculation and in situ spectroscopic results reveal that the abundant Cuδ+ sites display electron-donating ability, leading to the decrease of the reaction barrier in the potential-determining C−C coupling step and eventually making the applied potential close to the theoretical value.

  1. Metal-Free Nitrogen-Doped Mesoporous Carbon for Electroreduction of CO2 to Ethanol (Sci-Hub | Metal-Free Nitrogen-Doped Mesoporous Carbon for Electroreduction of CO2 to Ethanol. Angewandte Chemie International Edition, 56(36), 10840–10844 | 10.1002/anie.201706777)

Abstract: CO2 electroreduction is a promising technique for satisfying both renewable energy storage and negative carbon cycle. However, it remains a challenge to convert CO2 to C2 products with high efficiency and selectivity. Herein, we report a nitrogen-doped ordered cylindrical mesoporous carbon as a robust metal-free catalyst for CO2 electroreduction, enabling the efficient production of ethanol with nearly 100% selectivity and high faradaic efficiency of 77% at −0.56 V versus the reversible hydrogen electrode. Our experiments and density functional theory calculations demonstrate that the synergetic effect of the nitrogen heteroatoms and the cylindrical channel configurations facilitates the dimerization of key CO* intermediates and the subsequent proton-electron transfers, resulting in superior electrocatalytic performance for synthesizing ethanol from CO2.

This is great, Mike!

I went ahead and set up a group Zotero library for Air-Synth, and seeded it it with your papers as well as some I have been tracking in my personal reference library. Zotero is a free and open-source reference manager that is widely used by researchers, and has desktop and online access.

The library can be found here.

Right now I have a few categories, sorting papers by intended product/electrode etc. Most relevant to this group as I understand are copper-based electrodes aimed at ethanol production (a tall task, I will add - that’s a large molecular transformation, but it’s possible!).

I’m also in the process of linking this shared reference library to ResearchRabbit to help with lit review - through Zotero’s API, one can use ResearchRabbit to explore related papers in a graph network. Will post once this is operational (have to double check that ResearchRabbit can handle Group Libraries).

The library only tracks the references and doesn’t have attached files right now because 1. some of my files had watermarks/IP addresses traceable to my institution, which I’m not supposed to distribute and 2. I haven’t paid for cloud storage on Zotero. Most of these files should be available on Sci-Hub, preprint, or by contacting the author(s). I recommend the Sci-Hub Now and Unpaywall browser extensions for finding PDFs quickly.

Anyone can message me your email address and/or Zotero username, I can add members to the group as well as give admin/group owner status to people, etc (so it can be managed directly by OpenAir). Left group as invite-only so no rando can come in and delete everything.

Kirk

An aside: I like to be able to view items from subcollections (subfolders) in their parent collections (folders), but this is currently only possible in the desktop version of Zotero

Updated group library URL: Zotero | Groups > Air-Synth