Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China.
National Synchrotron Radiation Research Center, Hsinchu, Taiwan, ROC.
Nat Commun. 2023 Apr 13;14(1):2112. doi: 10.1038/s41467-023-37775-4.
Designing efficient catalyst for the oxygen evolution reaction (OER) is of importance for energy conversion devices. The anionic redox allows formation of O-O bonds and offers higher OER activity than the conventional metal sites. Here, we successfully prepare LiNiO with a dominant 3dL configuration (L is a hole at O 2p) under high oxygen pressure, and achieve a double ligand holes 3dL under OER since one electron removal occurs at O 2p orbitals for Ni oxides. LiNiO exhibits super-efficient OER activity among LiMO, RMO (M = transition metal, R = rare earth) and other unary 3d catalysts. Multiple in situ/operando spectroscopies reveal Ni→Ni transition together with Li-removal during OER. Our theory indicates that Ni (3dL) leads to direct O-O coupling between lattice oxygen and *O intermediates accelerating the OER activity. These findings highlight a new way to design the lattice oxygen redox with enough ligand holes created in OER process.
设计高效的氧气析出反应 (OER) 催化剂对于能量转换设备至关重要。阴离子氧化还原作用允许形成 O-O 键，并且比传统的金属位点具有更高的 OER 活性。在这里，我们在高氧压下成功制备了具有主导 3dL 构型的 LiNiO（L 是 O 2p 轨道上的空穴），并且由于 Ni 氧化物的 O 2p 轨道上发生了一个电子的去除，因此在 OER 下实现了双配体空穴 3dL。LiNiO 在 LiMO、RMO（M=过渡金属，R=稀土）和其他单价 3d 催化剂中表现出超高的 OER 活性。多种原位/操作光谱揭示了在 OER 过程中 Ni→Ni 转变伴随着 Li 的去除。我们的理论表明，Ni（3dL）导致晶格氧和 *O 中间体之间的直接 O-O 偶联，从而加速了 OER 活性。这些发现突出了一种新的设计具有足够配体空穴的晶格氧氧化还原的方法，这些空穴是在 OER 过程中产生的。
