send secret message to Saerom middle 1-7

Saerom middle 1-7

send me an anonymous message!

🔒 you are anonymous

Hey, did you check https://blablab.chat/en? I made so many new friends!

수행평가하고 준비물 공지 언제 바꿔요?

나도 몰라요 부반장이 귀찮다고하면 귀찮은거에요 당신도 귀찮으면 안하고 싶잖아요 ㅋ

Title: Synthesis and Characterization of a Cobalt-Based Catalyst for Hydrogen Evolution Reaction in Acidic Media Abstract Hydrogen evolution reaction (HER) is a key process in water splitting for sustainable hydrogen production. In this study, we synthesized a cobalt-based catalyst supported on nitrogen-doped carbon (Co/N–C) via a one-step pyrolysis method. The material exhibits high electrocatalytic activity in acidic media, showing an overpotential of 112 mV at 10 mA/cm² and a Tafel slope of 69 mV/dec. Structural characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) confirmed the uniform dispersion of cobalt nanoparticles and the successful incorporation of nitrogen into the carbon matrix. The catalyst demonstrates excellent durability over 24 hours of continuous operation. These findings highlight the potential of non-precious metal catalysts for cost-effective hydrogen production. Introduction As the demand for clean energy increases, hydrogen has emerged as a promising energy carrier. Among various production methods, electrochemical water splitting is environmentally friendly and can be powered by renewable energy. However, the efficiency of the hydrogen evolution reaction (HER) is limited by the high cost and scarcity of platinum-based catalysts. Therefore, developing low-cost, earth-abundant alternatives with high catalytic performance is crucial. Transition metals like cobalt have attracted attention due to their suitable electronic structure and moderate binding energy with hydrogen intermediates. In this work, we report the synthesis of a cobalt/nitrogen-doped carbon catalyst (Co/N–C) and investigate its HER activity in acidic media. Experimental Section Synthesis of Co/N–C Catalyst: A precursor mixture of cobalt nitrate and melamine was dissolved in ethanol, followed by drying and pyrolysis at 800°C under an inert atmosphere. The resulting black powder was washed with acid and water to remove unreacted species. Characterization: XRD patterns showed characteristic peaks of metallic Co and graphitic carbon. SEM images revealed porous carbon morphology with dispersed Co nanoparticles. XPS analysis confirmed the presence of Co²⁺/Co³⁺ and pyridinic and graphitic nitrogen species, which are known to enhance catalytic activity. Electrochemical Measurements: The HER performance was evaluated using a three-electrode system in 0.5 M H₂SO₄. Linear sweep voltammetry (LSV) revealed an overpotential of 112 mV at 10 mA/cm². The Tafel slope was calculated to be 69 mV/dec, suggesting a Volmer–Heyrovsky mechanism. Results and Discussion The enhanced HER performance of Co/N–C is attributed to the synergistic effect between cobalt nanoparticles and nitrogen-doped carbon. Nitrogen functionalities not only increase the electrical conductivity but also improve the adsorption of reaction intermediates. The stability test showed no significant degradation after 24 h operation, indicating excellent durability under acidic conditions. Conclusion We successfully synthesized a cobalt-based HER catalyst supported on nitrogen-doped carbon using a simple pyrolysis method. The material showed promising activity and stability, making it a viable alternative to precious metal catalysts for hydrogen production in acidic environments. 이 초안은 약 2000자 내외이며, 전형적인 **화학 논문 구성(IMRaD: Introduction, Methods, Results, and Discussion)**을 따릅니다. 원하시면 이 논문을 특정 주제, 실험 데이터, 그래프, 참고 문헌 등으로 확장하거나 포맷을 바꿔드릴 수 있어요. 주제나 세부 조건을 알려주시면 더 맞춤화된 논문을 드릴 수 있습니다.

박주원이 사회 얘기를 그만해줬으면 좋겠어요

최대한 사회 얘기를 안 하고 있는겁니다^^*~

애들이 너무 시끄러워서 수업에 집중이 안돼요

부반장으로써 너무 안타깝다고 생각합니다. 저희반을 더욱 멋있게 가꿔나가기 위해 노력하겠습니다

사랑이 힘들어요

힘들건 저희가 어떻게 해드릴 수가 없는 부분입니다. 아타깝습니다. 당신의 사랑이 이루어질 수 있도록 최대한 도와는 드리겠... 는 무슨 저희는 큐피드가 아니랍니다;;; 이런 익명은 자제 부탁드립니다유.

textm.ee - Get the app

Get Anonymous Messages