Shape-persistent phthalocyanine cages
Yiming Hu, Shaoda Huang, Lacey J. Wayment, Jingyi Wu, Qiucheng Xu, Tieyan Chang, Ying‐Pin Chen, Xiao‐Nian Li, Babak Andi, Hongxuan Chen, Yinghua Jin, Han Zhu, Mingliang Du, Shuanglong Lu, Wei Zhang
Abstract
Phthalocyanine (Pc), an electro-redox active moiety, has many attractive properties stemming from its large aromatic system and ability to act as a catalyst in electrochemical reactions, such as the CO2 reduction reaction (CO2RR). However, due to the synthetic challenge related to geometric requirements and poor solubility (strong aggregation), discrete shape-persistent cages consisting of site-isolated, readily accessible Pc moieties have not been available. Here, we report the synthesis of Zn- and Ni-metallated Pc-based molecular cages via one-step dynamic spiroborate linkage formation in high yields. The ZnPc cage structure is unambiguously elucidated at the atomic level by single-crystal X-ray diffraction. Moreover, owing to the site-isolated redox-active metal centers, readily accessible intrinsic cavity, and shape-persistent backbone, the Ni-metallated Pc (NiPc) cage exhibits high catalytic efficiency, selectivity, and stability, superior to the non-caged control molecules in electrocatalytic CO2RR.