촉매를 사용한 전기화학적 암모니아 생산은 주변 온도 및 압력 조건, 환경 친화적인 작동 및 고순도 암모니아 생산을

가능하게 함으로써 전통적인 하버-보쉬 방법을 대체할 대안으로서 가능성이 있다. 본 연구에서는 제1원리 계산을 사용

하여 루테늄 촉매의 표면에서 발생하는 질소 환원 반응에 초점을 맞춘다. 루테늄의 (0001) 및 (1000) 표면에서 질소 환

원에 대한 반응 경로를 모델링하여 반응 구조를 최적화하고 각 단계에 대한 유리한 경로를 예측했다. 각 표면에서의

N2의 흡착 구성은 후속 반응 활동에 상당한 영향을 미쳤으며, 깁스자유에너지 분석은 가장 유리한 질소 환원 구성을

도출하였다. 루테늄의 (0001) 표면에서는 질소 분자가 표면에 수직으로 흡착하는 end-on 형태가 가장 유리한 N2 흡착

에너지가 나타났으며 유사하게, (1000) 표면에서도 end-on 형태가 안정적인 흡착 에너지 값을 보였다. 이어서, distal

및 alternating 구성 모두에서 최적화된 수소 흡착을 통해 NH3의 최종 탈착까지 이론적으로 완전한 반응 경로를 설명했다.

Electrochemical ammonia production using catalysts offers a promising alternative to the conventional

Haber-Bosch process, allowing for ambient temperature and pressure conditions, environmentally friendly operations,

and high-purity ammonia production. In this study, we focus on the nitrogen reduction reactions occurring on the

surfaces of ruthenium catalysts, employing first-principles calculations. By modeling reaction pathways for nitrogen

reduction on the (0001) and (1000) surfaces of ruthenium, we optimized the reaction structures and predicted favorable

pathways for each step. We found that the adsorption configuration of N2 on each surface significantly influenced

subsequent reaction activities. On the (0001) surface of ruthenium, the end-on configuration, where nitrogen molecules

adsorb perpendicularly to the surface, exhibited the most favorable N2 adsorption energy. Similarly, on the (1000)

surface, the end-on configuration showed the most stable adsorption energy values. Subsequently, through optimized

hydrogen adsorption in both distal and alternating configurations, we theoretically elucidated the complete reaction

pathways required for the final desorption of NH3.

Ammonia, Ruthenium catalyst, Nitrogen reduction reactions, First-principles calculation

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