Advances and challenges of electrolyzers for large-scale CO_(2) electroreduction

CO_(2) electroreduction(CO_(2) ER)to high value-added chemicals is considered as a promising technology to achieve sustainable carbon neutralization.By virtue of the progressive research in recent years aiming at design and understanding of catalytic materials and electrolyte systems,the CO_(2) ER performance(such as current density,selectivity,stability,CO_(2) conversion,etc.)has been continually increased.Unfortunately,there has been relatively little attention paid to the large-scale CO 2 electrolyzers,which stand just as one obstacle,alongside series-parallel integration,challenging the practical application of this infant technology.In this review,the latest progress on the structures of low-temperature CO_(2) electrolyzers and scale-up studies was systematically overviewed.The influence of the CO_(2) electrolyzer configurations,such as the flow channel design,gas diffusion electrode(GDE)and ion exchange membrane(IEM),on the CO_(2) ER performance was further discussed.The review could provide inspiration for the design of large-scale CO_(2) electrolyzers so as to accelerate the industrial application of CO_(2) ER technology.

Thermodynamic analysis and modification of Gibbs–Thomson equation for melting point depression of metal nanoparticles

Abnormal melting point depression of metal nanoparticles often occurs in heterogeneous catalytic reactions,which leads to a reduction in the stability of reactive nanoclusters.To study this abnormal phenomenon,the original and surface-energy modified Gibbs-Thomson equations were analyzed in this work and further modified by considering the effect of the substrate.The results revealed that the original Gibbs-Thomson equation was not suitable for the particles with radii smaller than 10 nm.Moreover,the performance of the surface-energy modified Gibbs-Thomson equation was improved,and the deviation was reduced to(-350-100)K,although further modification of the equation by considering the interfacial effect was necessary for the small particles(r<5 nm).The new model with the interfacial effect improved the model performance with a deviation of approximately-50 to 20 K,where the interfacial effect can be predicted quantitatively from the thermodynamic properties of the metal and substrate.Additionally,the micro-wetting parameterα_W can be used to qualitatively study the overall impact of the substrate on the melting point depression.

CO_2/N_2 separation using supported ionic liquid membranes with green and cost-effective [Choline][Pro]/PEG200 mixtures

The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][Pro]/polyethylene glycol 200(PEG200) mixtures were selected to prepare novel SILMs because of their green and costeffective characterization, and the CO_2/N_2 separation with the prepared SILMs was investigated experimentally at temperatures from 308.15 to 343.15 K. The temperature effect on the permeability, solubility and diffusivity of CO_2 was modeled with the Arrhenius equation. A competitive performance of the prepared SILMs was observed with high CO_2 permeability ranged in 343.3–1798.6 barrer and high CO_2/N_2 selectivity from 7.9 to 34.8.It was also found that the CO_2 permeability increased 3 times by decreasing the viscosity of liquids from 370 to38 m Pa·s. In addition, the inherent mechanism behind the significant permeability enhancement was revealed based on the diffusion-reaction theory, i.e. with the addition of PEG200, the overall resistance was substantially decreased and the SILMs process was switched from diffusion-control to reaction-control.

离子液体捕集二氧化碳非平衡热力学研究方法学探讨

介绍了应用非平衡热力学研究离子液体捕集二氧化碳(CO2)动力学的思路,分析了其成功应用需解决三大关键科学难题,即可靠的热力学模型,界面传递速率描述以及准确的通量数据.其中,准确通量数据的获得需要可靠的实验动力学数据和离子液体捕集CO2过程传递面积的有效考察.在此基础上系统地总结了该三大关键科学问题最新的研究进展和分析后续开展的工作,并对离子液体捕集二氧化碳非平衡热力学研究提出展望.