Wan Gang, Freeland John W, Kloppenburg Jan, Petretto Guido, Nelson Jocienne N, Kuo Ding-Yuan, Sun Cheng-Jun, Wen Jianguo, Diulus J Trey, Herman Gregory S, Dong Yongqi, Kou Ronghui, Sun Jingying, Chen Shuo, Shen Kyle M, Schlom Darrell G, Rignanese Gian-Marco, Hautier Geoffroy, Fong Dillon D, Feng Zhenxing, Zhou Hua, Suntivich Jin
Materials Science Division, Argonne National Laboratory, Lemont, IL 60439, USA.
X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA.
Sci Adv. 2021 Jan 8;7(2). doi: 10.1126/sciadv.abc7323. Print 2021 Jan.
The use of renewable electricity to prepare materials and fuels from abundant molecules offers a tantalizing opportunity to address concerns over energy and materials sustainability. The oxygen evolution reaction (OER) is integral to nearly all material and fuel electrosyntheses. However, very little is known about the structural evolution of the OER electrocatalyst, especially the amorphous layer that forms from the crystalline structure. Here, we investigate the interfacial transformation of the SrIrO OER electrocatalyst. The SrIrO amorphization is initiated by the lattice oxygen redox, a step that allows Sr to diffuse and O to reorganize the SrIrO structure. This activation turns SrIrO into a highly disordered Ir octahedral network with Ir square-planar motif. The final Sr IrO exhibits a greater degree of disorder than IrO made from other processing methods. Our results demonstrate that the structural reorganization facilitated by coupled ionic diffusions is essential to the disordered structure of the SrIrO electrocatalyst.
利用可再生电力从丰富的分子制备材料和燃料，为解决能源和材料可持续性问题提供了一个诱人的机会。析氧反应（OER）几乎是所有材料和燃料电合成过程中不可或缺的一部分。然而，对于OER电催化剂的结构演变，尤其是从晶体结构形成的非晶层，人们了解甚少。在此，我们研究了SrIrO OER电催化剂的界面转变。SrIrO的非晶化是由晶格氧氧化还原引发的，这一步骤使得Sr能够扩散，O能够重组SrIrO结构。这种活化将SrIrO转变为具有Ir方形平面 motif的高度无序的Ir八面体网络。最终的SrIrO比通过其他加工方法制备的IrO表现出更大程度的无序。我们的结果表明，由耦合离子扩散促进的结构重组对于SrIrO电催化剂的无序结构至关重要。
