监督人工智能和深度神经网络来评估高合金作为水性环境中的还原催化剂
Rafael B Araujo1, Tomas Edvinsson1,2
1Department of Materials Science and Engineering, Solid State Physics, Uppsala University, Box 35, 75103 Uppsala, Sweden.
概括
深度神经网络加速研究用于氨合成的高合金. 仅仅是催化剂设计是不够的;氧气/排斥策略对于有效的降低至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 电化学 电化学 电化学
背景情况:
- 建模电化学反应需要理解表面吸附能.
- 密度函数理论 (DFT) 对复杂系统来说是计算密集型的.
- 高合金 (HEAs) 显示出作为电催化剂的前景.
研究的目的:
- 开发一种新的方法来量化复杂的催化表面上的竞争性吸附.
- 研究用于电化学氨基合成的高合金.
- 为了确定目前用于降低的催化剂设计的局限性.
主要方法:
- 利用量子力学引导的深度神经网络 (DNN).
- 应用了研究Mo-Cr-Mn-Fe-Co-Ni-Cu-Zn高合金的方法.
- 分析了氨合成的吸附能量和反应途径.
主要成果:
- 对于复杂的系统,DNN为DFT提供了一个计算效率高的替代方案.
- 确定了特定的HEA组合物作为潜在的电催化剂.
- 即使在有利的条件下, (N2) 覆盖率仍然很低,这表明固化的程度有限.
结论:
- 仅仅是催化剂的优化不足以实现高效的电化学缩.
- 需要采用氧气和排斥策略的系统设计.
- 高压溶液也可以增强水性的减少.
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