The efficiency of green hydrogen production through photo- or electrochemical splitting of water depends strongly on the catalyst used. Several 2D materials have recently been proposed as effective catalysts or...

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The conversion of CO2 to fine chemicals is an efficient tool for reducing the negative impact of human activities on the environment. In this work, we show that CO2 capture and its sunlight-based activation can proceed efficiently even at low, practically arctic temperatures with the implementation of so-called plasmon-assisted chemistry. We propose the specific photocatalyst consisting of two parts: (i) an organic shell responsible for CO2 capture and (ii) a plasmon-active metal nanoparticle core for activation of entrapped CO2 and involving it in the cycloaddition reaction. The effect of temperature on the plasmon-assisted CO2 cycloaddition was studied, and a reaction with only slight temperature sensitivity was observed. Theoretical calculations indicated a significant decrease in the “apparent” activation barrier of the reaction under the plasmon-assisted mechanism. Our results open an opportunity for the world economy to exploit the vast Arctic and Antarctic (or close to them) territories where the powerful solar potential is practically not used yet.

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Ammonia is one of the most widely produced chemicals worldwide, which is consumed in the fertilizer industry and is also considered an interesting alternative in energy storage. However, common ammonia production is energy-demanding and leads to high CO2 emissions. Thus, the development of alternative ammonia production methods based on available raw materials (air, for example) and renewable energy sources is highly demanding. In this work, we demonstrated the utilization of TiB2 nanostructures sandwiched between coupled plasmonic nanostructures (gold nanoparticles and gold grating) for photoelectrochemical (PEC) nitrogen reduction and selective ammonia production. The utilization of the coupled plasmon structure allows us to reach efficient sunlight capture with a subdiffraction concentration of light energy in the space, where the catalytically active TiB2 flakes were placed. As a result, PEC experiments performed at −0.2 V (vs. RHE) and simulated sunlight illumination give the 535.2 and 491.3 μg h–1 mgcat –1 ammonia yields, respectively, with the utilization of pure nitrogen and air as a nitrogen source. In addition, a number of control experiments confirm the key role of plasmon coupling in increasing the ammonia yield, the selectivity of ammonia production, and the durability of the proposed system. Finally, we have performed a series of numerical and quantum mechanical calculations to evaluate the plasmonic contribution to the activation of nitrogen on the TiB2 surface, indicating an increase in the catalytic activity under the plasmon-generated electric field.