They were grown using DC-magnetron sputtering in the presence of an N 2 plasma atmosphere at the experimental station of the soft XAS beamline BL01 (Indus-2, RRCAT, India). XANES measurements were performed at the N K -edge in all three cases. It was found that the N K -edge ...
总之,本研究通过快速焦耳热合成方法将钌(Ru)单原子嵌入到Ni3FeN的次表面晶格中,制备了Ni3FeN-Ruburied催化剂,以实现高效的碱性甲醇转化为甲酸。通过X射线吸收光谱(XAS)和密度泛函理论(DFT)计算,明确了嵌入的Ru原子的配位环境,揭示了...
考虑到微孔主要提供催化活性位点,介孔结构可以改善传质,选择具有理想微/介孔分布的 N/SGr-1作为支持Cu原子的首选载体。用SEM,HRTEM,XRD,HAADF-STEM,XAS等对催化剂g-Cu-SACs做了表征,文章里有详细介绍,这里不多做赘述,主要证明了g-C...
然而,电感耦合等离子体(ICP)光学发射光谱测量(表S2,支持信息)显示,每种催化剂的Cu负载约为3-4 wt%,表明很大一部分Cu被限制在碳结构中。 为了阐明催化剂中Cu的配位结构,我们采用了x射线吸收光谱(XAS)在Cu的k边。催化剂的x射线吸收近边结构(XANES)光谱(图1h,i)彼此相似,与其他具有相似Cu-N4配位的化合物相似,...
(c)Co4N和Co3CuN的N K-edge光谱。(d)Co4N(左)和Co3CuN(右)的电荷分布较差。(e)Co4N和Co3CuN的Co L-edge XAS光谱。(f)Co4N和Co3CuN中Co-3d的d轨道的部分态密度(PDOS)。(g)Co4N和Co3CuN的能带示意图。(h)Co4N和Co3CuN的XPS价带谱。
考虑到微孔主要提供催化活性位点,介孔结构可以改善传质,选择具有理想微/介孔分布的 N/SGr-1作为支持Cu原子的首选载体。用SEM,HRTEM,XRD,HAADF-STEM,XAS等对催化剂g-Cu-SACs做了表征,文章里有详细介绍,这里不多做赘述,主要证明了g-Cu-SACs中孤立分散的单原子位点及周围的化学配位结构与环境(图3,图4)。
最后,采用原位同步辐射吸收光谱(In situXAS)对反应过程中e-OD-Cu催化剂的价态和配位环境进行监测,数据表明其基本能够维持稳定。同时,用OCP和DFT计算对Cu空位的作用进行了深入分析,研究表明其能增强硝酸盐的吸附并抑制CH2=NH的氢化,抑制副产物(甲胺、二甲胺、三甲胺)生成。
(c-d)这两种催化剂的X射线吸收光谱(XAS)分析:R空间中的傅里叶变换EXAFS和Fe K- edge XANES光谱; (e-f)通过AST在O2饱和0.5 M H2SO4中循环电位,两种催化剂的初始活性和稳定性结果。 图三、Fe-AC和Fe-AC-CVD阴极催化剂的MEA性能© 2022 Springer Nature Limited ...
Ni K-edge XAS data is consistent with Ni(II) ligated by five N/O based ligands (three N/O ligands at 2.01(2) Angstrom and two at 1.855(2) Angstrom). We were also able to locate a Ni-Ni vector at 3.1(1) Angstrom, which suggests the two Ni(II) centers are contained in a bis...
Ni K-edge XAS data is consistent with NiII ligated by five N/O based ligands (three N/O ligands at 2.01(2) Å and two at 1.855(2) Å). We were also able to locate a Ni–Ni vector at 3.1(1) Å, which suggests the two NiII centers are contained in a bis-μ-hydroxo ...