Photoexcitation of Fe 3 O Nodes in MOF Drives Water Oxidation at pH=1 When Ru Catalyst Is Present
Photoexcitation of Fe 3 O Nodes in MOF Drives Water Oxidation at pH=1 When Ru Catalyst Is Present
复制标题
当 Ru 催化剂存在时，MOF 中 Fe 3 O 节点的光激发在 pH=1 时驱动水氧化
DOI：
10.1002/cssc.202202124
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发表时间：
2023
期刊：
影响因子：
8.4
通讯作者：
Pushkar, Yulia
中科院分区：
文献类型：
--
作者：
Ezhov, Roman;Ravari, Alireza K.;Palenik, Mark;Loomis, Alexander;Meira, Debora M.;Savikhin, Sergei;Pushkar, Yulia
人工光合作用致力于将阳光的能量转化为可持续的、生态友好的太阳能燃料。然而，在pH=1下具有光驱动水氧化反应（WOR）的系统是罕见的。广泛使用的[Ru（bpy）3]2+（bpy= 2，2 '-bipyridine）光敏剂具有固定的+1.23 V电位，这不足以在酸中驱动大多数水氧化催化剂（WOCs），而Fe 2 O3具有高氧化性空穴，在低pH下不稳定。 Fe-MIL-126和Fe M0 F-dcbpy结构由4，4 '-联苯基二羧酸酯（bpdc）、2，2'-联吡啶-5，5 '-二羧酸酯（dcbpy）连接体及其混合物形成。dcbpy连接体的存在允许金属基催化剂通过配位到2，2 '-联吡啶片段的整合。用Ru基前体掺杂Fe基M0 F以获得具有[Ru（bpy）（dcbpy）（H2O）2]2+WOC的高活性M0 F。采用X射线衍射（XRD）、扫描电子显微镜（SEM）、傅里叶变换红外（FTIR）光谱、共振拉曼、X射线吸收光谱、fs光泵浦-探测、电子顺磁共振（EPR）、漫反射和电导率测量对材料进行分析，并通过能带结构计算进行建模。结果表明，在反应条件下，存在FeIII和RuIII氧化态，表明MOF中的速率限制电子转移。Fe 3 O节点作为光敏剂出现，能够驱动酸中长时间的O2释放。进一步的发展是可能的，通过MOF的连接体修饰增强光吸收，导电性，降低MOF在酸中的溶解度，Ru-WOC修饰更快的WOC催化，或Ru-WOC取代3d金属基系统。这些发现为基于地球丰富金属的光驱动水分解系统的开发提供了进一步的见解。
Artificial photosynthesis strives to convert the energy of sunlight into sustainable, eco‐friendly solar fuels. However, systems with light‐driven water oxidation reaction (WOR) at pH=1 are rare. Broadly used [Ru(bpy)3]2+(bpy=2,2’‐bipyridine) photosensitizer has a fixed +1.23 V potential which is insufficient to drive most water oxidation catalysts (WOCs) in acid, while Fe2O3, featuring the highly oxidizing holes, is not stable at low pH. Here, the key examples of Fe‐based metal–organic framework (MOF) water oxidation photoelectrocatalysts active at pH=1 are presented. Fe‐MIL‐126 and Fe MOF‐dcbpy structures were formed with 4,4’‐biphenyl dicarboxylate (bpdc), 2,2’‐bipyridine‐5,5’‐dicarboxylate (dcbpy) linkers and their mixtures. Presence of dcbpy linkers allows integration of metal‐based catalysts via coordination to 2,2’‐bipyridine fragments. Fe‐based MOFs were doped with Ru‐based precursors to achieve highly active MOFs bearing [Ru(bpy)(dcbpy)(H2O)2]2+WOC. Materials were analyzed with X‐ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra‐red (FTIR) spectroscopy, resonance Raman, X‐ray absorption spectroscopy, fs optical pump‐probe, electron paramagnetic resonance (EPR), diffuse reflectance and electric conductivity measurements and were modeled by band structure calculations. It is shown that under reaction conditions, FeIIIand RuIIIoxidation states are present, indicating rate‐limiting electron transfer in MOF. Fe3O nodes emerge as photosensitizers able to drive prolonged O2evolution in acid. Further developments are possible via MOF's linker modification for enhanced light absorption, electrical conductivity, reduced MOF solubility in acid, Ru‐WOC modification for faster WOC catalysis, or Ru‐WOC substitution to 3d metal‐based systems. The findings give further insight for development of light‐driven water splitting systems based on Earth‐abundant metals.