Achieving the Widest Range of Syngas Proportions at High Current Density over Cadmium Sulfoselenide Nanorods in CO₂ Electroreduction

Abstract

Electroreduction of CO is a sustainable approach to produce syngas with controllable ratios, which are required as specific reactants for the optimization of different industrial processes. However, it is challenging to achieve tunable syngas production with a wide ratio of CO/H , while maintaining a high current density. Herein, cadmium sulfoselenide (CdS Se ) alloyed nanorods are developed, which enable the widest range of syngas proportions ever reported at the current density above 10 mA cm in CO electroreduction. Among CdS Se nanorods, CdS nanorods exhibit the highest Faradaic efficiency (FE) of 81% for CO production with a current density of 27.1 mA cm at -1.2 V vs. reversible hydrogen electrode. With the increase of Se content in CdS Se nanorods, the FE for H production increases. At -1.2 V vs. RHE, the ratios of CO/H in products vary from 4:1 to 1:4 on CdS Se nanorods (x from 1 to 0). Notably, all proportions of syngas are achieved with current density higher than ≈25 mA cm . Mechanistic study reveals that the increased Se content in CdS Se nanorods strengthens the binding of H atoms, resulting in the increased coverage of H* and thus the enhanced selectivity for H production in CO electroreduction.

Zn–Cu Alloy Nanofoams as Efficient Catalysts for the Reduction of CO2 to Syngas Mixtures with a Potential‐Independent H2/CO Ratio

“…Previous reports have focused on monometallic molecular and heterogeneous catalytic systems, which have been used for simultaneous production of CO and H 2 . However, single catalytic sites offer limited possibilities for selective tuning of the catalyst.…”

“…Previous reports have focusedo nm onometallic molecular [4][5][6] and heterogeneousc atalytic systems, [7][8][9][10][11][12][13][14][15] which have been used fors imultaneous production of CO and H 2 .H owever,s ingle catalytic sites offer limited possibilities for selective tuning of the catalyst. Introducing as econd metal site offers an extra degree of freedom in catalystd esign ando ffers the best route to address the above criteria.…”

Progress in development of electrocatalyst for CO2 conversion to selective CO production

“…Forms of metal oxides and sulfides were recently studied as non‐noble materials that are potential catalysts for the CO 2 ‐to‐CO reaction . For instance, CdS nanorods catalysts obtained CO FE of 81% and a current density of 27.1 mA cm –2 at –1.2 V RHE , and Co 3 O 4 ‐CDots‐C 3 N 4 composite obtained a maximum CO FE of 89% at –0.6 V RHE over 30 hours . Those reports then adjusted the composition of electrocatalysts to tune the desired H 2 /CO ratio for the syngas generation, following some reported with noble nanohybrid catalysts …”

Porous Palladium Nanomeshes with Enhanced Electrochemical CO2‐into‐Syngas Conversion over a Wider Applied Potential

“…[1][2][3] Syngas, made up of CO and H 2 ,i savital feedstock for the production of synfuel and industrial chemicals through classicalp etroleum industry processes, [4] for example, the optimal CO/H 2 = 1:2f or methanolb yt he Fischer-Tropsch synthesis, and CO/H 2 = 1:1f or the hydroformylation process. [7,8] On the one hand, the CO/H 2 ratio of generated syngasc an be tunable by controlling the electrochemical potential;o nt he other hand, it can avoid the traditional production of syngast hrough the consumption of nonrenewablef ossil fuels and thus alleviate atmosphericCO 2 production. [7,8] On the one hand, the CO/H 2 ratio of generated syngasc an be tunable by controlling the electrochemical potential;o nt he other hand, it can avoid the traditional production of syngast hrough the consumption of nonrenewablef ossil fuels and thus alleviate atmosphericCO 2 production.…”