Ammonia (NH_(3)) plays a key role in the agricultural fertilizer and commodity chemical industries and is useful for exploring hydrogen storage carriers.The electrochemical nitrogen reduction reaction (NRR) is receivi...Ammonia (NH_(3)) plays a key role in the agricultural fertilizer and commodity chemical industries and is useful for exploring hydrogen storage carriers.The electrochemical nitrogen reduction reaction (NRR) is receiving attention as an environmentally sustainable NH_(3) synthesis replacement for the traditional Haber–Bosch process owing to its near ambient reaction conditions (<100℃ and 1 atm).However,its NH_(3) yield and faradaic efficiency are extremely low because of the sluggish kinetics of N≡N bond dissociation and the hindrance from competitive hydrogen evolution.To overcome these challenges,we herein introduce a dual-functionalized ionic liquid (1-(4-hydroxybutyl)-3-methylimidazolium hydroxide[HOBIM]OH) for a highly dispersed ruthenium oxide electrocatalyst to achieve a biased NRR.The observed uniform distribution of RuO_(2) on the carbon fiber and increase in the surface area for N_(2) adsorption by limiting proton access can be attributed to the presence of imidazolium ions.Moreover,extensive N_(2) adsorption contributes to enhanced NRR selectivity with an NH_(3) yield of 3.0×10^(-10)mol cm^(-2)s^(-1)(91.8μg h^(-1)mg^(-1)) and a faradaic efficiency of 2.2%at-0.20 V_(RHE).We expect our observations to provide new insights into the design of effective electrode structures for electrochemical NH;synthesis.展开更多
A new type of a high temperature liquid metal-air energy storage cell based on solid oxide electrolyte has been successfully demonstrated at 750 ℃ by feeding metal Sn. In order to understanding the initial size effec...A new type of a high temperature liquid metal-air energy storage cell based on solid oxide electrolyte has been successfully demonstrated at 750 ℃ by feeding metal Sn. In order to understanding the initial size effect of metal as a liquid fuel, we report here the impact of the thermal and electrochemical oxidation behavior of nano Sn （-100 nm）, comparing with micro-sized （-5 μm） and macro-sized （4350 μm） Sn. The thermogravimetric analysis and the monitoring OCV test indicate that the distinct property of nano-sized Sn results in a favorable thermal oxidation behavior near the melting point and a promising power performance due to enhanced fuel transport to the anode. However, the accumulated Sn oxide at the reaction interface during a discharge test towards the limitation of further electrochemical oxidation.展开更多
基金supported by the National R&D Program through the National Research Foundation of Korea(NRF)funded by Ministry of Science and ICT(2021K1A4A8A01079455)。
文摘Ammonia (NH_(3)) plays a key role in the agricultural fertilizer and commodity chemical industries and is useful for exploring hydrogen storage carriers.The electrochemical nitrogen reduction reaction (NRR) is receiving attention as an environmentally sustainable NH_(3) synthesis replacement for the traditional Haber–Bosch process owing to its near ambient reaction conditions (<100℃ and 1 atm).However,its NH_(3) yield and faradaic efficiency are extremely low because of the sluggish kinetics of N≡N bond dissociation and the hindrance from competitive hydrogen evolution.To overcome these challenges,we herein introduce a dual-functionalized ionic liquid (1-(4-hydroxybutyl)-3-methylimidazolium hydroxide[HOBIM]OH) for a highly dispersed ruthenium oxide electrocatalyst to achieve a biased NRR.The observed uniform distribution of RuO_(2) on the carbon fiber and increase in the surface area for N_(2) adsorption by limiting proton access can be attributed to the presence of imidazolium ions.Moreover,extensive N_(2) adsorption contributes to enhanced NRR selectivity with an NH_(3) yield of 3.0×10^(-10)mol cm^(-2)s^(-1)(91.8μg h^(-1)mg^(-1)) and a faradaic efficiency of 2.2%at-0.20 V_(RHE).We expect our observations to provide new insights into the design of effective electrode structures for electrochemical NH;synthesis.
基金the financial support from the R&D Convergence Program of NST (National Research Council of Science & Technology) of Republic of Korea
文摘A new type of a high temperature liquid metal-air energy storage cell based on solid oxide electrolyte has been successfully demonstrated at 750 ℃ by feeding metal Sn. In order to understanding the initial size effect of metal as a liquid fuel, we report here the impact of the thermal and electrochemical oxidation behavior of nano Sn （-100 nm）, comparing with micro-sized （-5 μm） and macro-sized （4350 μm） Sn. The thermogravimetric analysis and the monitoring OCV test indicate that the distinct property of nano-sized Sn results in a favorable thermal oxidation behavior near the melting point and a promising power performance due to enhanced fuel transport to the anode. However, the accumulated Sn oxide at the reaction interface during a discharge test towards the limitation of further electrochemical oxidation.
