Inorganic porous materials are prevailing in energy storage, environment remediation, and catalysis; however, it is attractive to control the spatial arrangement of heterometals in these materials with atomic accuracy. Here, we report the precise positioning of metals with identical valence, coordination number, and similar size, such as Zn (II) and Co (II), to generate an alternating sequence in a multivariate (MTV) metal-organic framework (MOF), ZnCo-MTV-MOF-699, with a rare sheet secondary building unit. This is achieved by precoding their coordination number in a parent MOF, ZnCo-MOF-69C, followed by single-crystal-to-single-crystal transformation, where the entire process is monitored in situ by time-resolved small-angle X-ray scattering. Coordination number precoding of other metal pairs, Zn-Ni and Zn-Cu, in MTV-MOFs is also obtained. The sequence-coded MTV-MOF exhibits a much lower overpotential than that of the non-coded counterpart in oxygen evolution reaction, unveiling the power of metal sequence control.

无机多孔材料在储能、环境修复、催化等领域占主导地位；然而，以原子精度控制这些材料中异质金属的空间排列是有吸引力的。在这里，我们报告了具有相同化合价、配位数和相似尺寸的金属（例如 Zn (II) 和 Co (II)）的精确定位，以在多元 (MTV) 金属有机框架 (MOF) 中生成交替序列，ZnCo-MTV-MOF-699，具有稀有片材二次建筑单元。这是通过在母体 MOF 中预编码它们的配位数 ZnCo-MOF-69C 来实现的，然后进行单晶到单晶的转变，在原位监控整个过程通过时间分辨小角 X 射线散射。还获得了 MTV-MOF 中其他金属对 Zn-Ni 和 Zn-Cu 的配位数预编码。序列编码的 MTV-MOF 在析氧反应中表现出比非编码对应物低得多的过电位，揭示了金属序列控制的能力。