NSF-DFG Echem: Electrochemically enhanced low-temperature catalytic ammonia synthesis

NSF-DFG Echem：电化学增强低温催化氨合成

• 批准号: 2140971
• 负责人: Robert Kee
• 金额: $ 37.56万
• 依托单位: Colorado School of Mines
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2140971&HistoricalAwards=false
• 关键词: NSF; DFG; Echem; Electrochemically; enhanced

As the nation and the world move toward carbon-free energy economies, ammonia will likely play significant roles as a hydrogen carrier. Today, essentially all ammonia is produced in high pressure Haber-Bosch plants at very large scale. There is a growing need for smaller scale, geographically distributed, ammonia synthesis using renewable resources. However, because of inherent thermodynamic and kinetic limitations, typical catalyst-based thermal processes (e.g., Haber-Bosch) are not economic at smaller scale. The present project seeks to enable distributed ammonia synthesis using electrochemical interactions that significantly reduce activation barriers. The research relies on the combined, complementary, and unique expertise of the partners in the context of materials synthesis, characterization and process demonstration (KIT) and physically based modeling of the electrochemistry, charged-defect transport, and catalysis (CSM).This joint project addresses significant scientific challenges in transitioning to environmentally friendly ammonia production as an energy carrier and commodity chemical. The project’s objective is to develop and demonstrate electrochemical enhancement that enables low-temperature and low-pressure ammonia synthesis. Nanophase Ru is dispersed on a proton-conducting BCZY support (BaCe1-x-yZrxYyO3-δ). Directly polarizing the catalyst structure with an electric field decreases the kinetically limiting barrier for N2 activation. Although the proposed research is scientifically fundamental, it has excellent technology potential for cost-effective distributed production of ammonia. The research focuses on postulating, modeling, and validating proposed chemical behaviors. The electrical field is expected to reduce rate-limiting N2 dissociation barriers via two synergistic mechanisms:1. Electrical fields affect the proton-conducting BCZY support, enabling H2 dissociation to form protons that can activate gas-phase N2, directly forming desired surface adsorbates such as NH on the BCZY support.2. Fields in the range of 0.1 to1.0 V/Å on dispersed nano-Ru also reduce the nitrogen activation barrier. The energy barrier for nitrogen activation Ru varies between 30-42 kJ mol-1. Based on our validated reaction mechanisms for Ba-promoted Ru/YSZ, simulations show that reducing the N2 dissociation energy by 10 kJ mol-1 will increase the ammonia formation rate by an order of magnitude.This research was funded under the NSF-DFG Lead Agency Activity in Electrosynthesis and Electrocatalysis (NSF-DFG EChem) opportunity NSF 20-578.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

随着国家和世界走向无碳能源经济，氨可能会作为氢载体发挥重要作用，今天，基本上所有氨都是在哈伯-博世高压工厂大规模生产的，对氨的需求不断增长。然而，由于固有的热力学和动力学限制，典型的基于催化剂的热工艺（例如哈伯-博世）在较小规模下并不经济。该研究依赖于合作伙伴在材料合成、显着表征和过程演示 (KIT) 以及电化学、带电物理建模方面的综合、互补和独特的专业知识。缺陷传输和催化（CSM）。该联合项目解决了向环境友好型氨生产过渡作为能源载体和商品化学品的重大科学挑战。该项目的目标是开发和演示能够实现低温和大宗化学品的电化学增强。低压氨合成。纳米相 Ru 分散在质子传导 BCZY 载体 (BaCe1-x-yZrxYyO3-δ) 上，用电场直接极化催化剂结构会降低 N2 活化的动力学限制势垒。从科学的角度来看，它具有经济高效的分布式氨生产的巨大技术潜力。该研究的重点是假设、建模和验证所提出的化学行为。通过两种协同机制减少 N2 解离速率限制：电场影响质子传导 BCZY 载体，使 H2 解离形成可以激活气相 N2 的质子，直接在 BCZY 载体上形成所需的表面吸附物，例如 NH。 .2. 分散的纳米 Ru 上 0.1 至 1.0 V/Å 范围内的场也降低了氮活化势垒。 30-42 kJ mol-1。基于我们验证的 Ba 促进的 Ru/YSZ 反应机制，模拟表明，将 N2 解离能降低 10 kJ mol-1 将使氨的形成速率提高一个数量级。这项研究获得 NSF-DFG 电合成和电催化牵头机构活动 (NSF-DFG EChem) 机会 NSF 20-578 的资助。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。