Search

• Electrodeposition of tellurium from deep eutectic solvents can produce nanowires. • Tellurium nanostructure is strongly dependent on deposition conditions. • Swapping chloride for iodide produces nanoplatelets in place of nanowires. • Tellurium nucleation is kinetically slower in chloride than bromide and iodide, which impacts subsequent nanostructures. Electrochemical deposition of tellurium from deep eutectic solvents (DES) at gold film electrodes produced films of tellurium nanowires. The deposition was evenly distributed over the gold surface, with an average diameter of ∼70 nm and length of ∼1 µm. Deposition was extremely sensitive to the applied potential, tellurium concentration and deposition bath temperature, with deviations away from optimised conditions preventing the formation of the desired nanostructure. Interestingly, replacing the chloride in a popular eutectic solvent with bromide or iodide had a significant impact on the resultant film structure, with bromide giving no clearly defined nanostructure but iodide giving nanoplatelets. This demonstrates a strong control of tellurium nanostructure by halide ions, offering a way to two distinct nanostructures from the same core experimental set up. [Display omitted] [ABSTRACT FROM AUTHOR]

CO 2 reduction offers an attractive alternative green synthetic route for ethylene, especially where CO 2 could be sourced from industrial exhausts and in combination with green power sources. However, practical applications are currently limited due to the unfortunately low selectivity of cathode materials towards ethylene. This work uses polymers with intrinsic microporosity (PIMs) to improve the performance of copper gas diffusion electrodes for CO 2 reduction to ethylene. We report an improved selectivity and activity towards ethylene with the addition of a thin PIMs layer, which is seen as improved Faradaic efficiency, increased stability and a shift in the reduction to lower overpotential. This improvement is highly dependent on the thickness of the added polymer layer, with too thick a layer having a detrimental impact on the hydrophobicity of the gas diffusion layer. With a compromise in loading, PIMs can be used to enhance the activity and selectivity of catalysts for targeted CO 2 reduction to ethylene. Image 10694 • Gas diffusion electrodes allow CO 2 reduction to ethylene, but selectivity is low. • Polymers with intrinsic microporosity can increase ethylene production. • Using too much polymer has a detrimental impact. • A compromise polymer thickness increases ethylene yield and electrode stability. [ABSTRACT FROM AUTHOR]