All‐Conjugated Microporous Polymer Heterojunction with Hierarchical Hollow Sphere Architecture for Photocatalytic H 2 O 2 Production

Abstract Conjugated microporous polymers (CMPs) have emerged as a class of promising organic photocatalysts due to their tailorable polymer monomers, tunable molecular orbitals, diverse synthesis strategies, etc. However, as with most single photocatalysts, even finely designed CMPs are still subject to the recombination of photogenerated carriers, making it difficult to perform photocatalysis effectively. Herein, two types of CMPs containing pyrazine and benzothiadiazole units (labeled as PzTP and BTTP, respectively) are purposely designed and successfully assembled them into hierarchical hollow spheres (PzTP@BTTP) by sequential polymerization on sacrificial templates. It is demonstrated that these two CMPs with matched orbital energy level structures effectively form a Z‐scheme heterojunction with photoelectronic properties superior to those of a single CMP. Particularly, the PzTP@BTTP hollow heterojunction CMP is capable of generating H 2 O 2 as high as 8.19 mmol g −1 h −1 in pure water under blue light irradiation, and even 20.49 mmol g −1 h −1 using benzyl alcohol as a hole sacrificial agent, exhibiting great competitiveness in this field. This work suggests that it is feasible to construct efficient heterojunction photocatalysts by rationally combining CMPs with different energy level structures, which opens up new avenues for expanding the research of CMP‐involved organic semiconductors in the photocatalysis area.