It is challenging for polymer photocatalysts to achieve high photocatalytic performance under visible light due to their weak light absorption in visible light region. Herein, a universal strategy for boosting the photocatalytic activity of donor-acceptor (D-A) conjugated polymer photocatalysts upon visible light irradiation by inserting a π-spacer of thiophene unit between the electron donors and acceptors to form a D-π-A molecular structure is reported. The introduction of thiophene unit with narrow band gap can enhance the conjugation degree of the polymer chains and extend the light absorption range. Meanwhile, the introduction of thiophene spacer through ternary copolymerization also enables the controllability on the chemical structure of the resulting D-π-A polymers by altering the feed ratio between the electron donors and acceptors. The optimized D-π-A copolymer photocatalyst shows an impressive hydrogen evolution rate (HER) of 78.4 mmol h -1 g -1 under visible light irradiation, and the HER could be further improved to 127.9 mmol h -1 g -1 under UV-vis light irradiation by loading 1 wt% Pt co-catalyst. More importantly, this strategy can also be extended to other polymeric photocatalysts with different donor and acceptor units, demonstrating the universality for enhancing the photocatalytic activity of polymeric photocatalysts.

electronic structure. [3][4][5] Nevertheless, most inorganic photocatalysts suffer from low activity under visible light, complexity in the preparation, and the limited natural resources. Recent studies demonstrated that organic semiconductors could be a promising class of photocatalysts for hydrogen evolution because of their diverse structures, various synthetic strategies, and tunable electronic properties. [6][7][8] To date, various organic polymers with conjugated skeletons have been developed as photocatalysts for hydrogen evolution. [9][10][11] In particular, significant advances in the preparation of conjugated microporous polymer (CMP) photocatalysts with high photocatalytic activity have been achieved. [12][13][14] Many studies revealed that designing a donor-acceptor (D-A) molecular structure is an efficient strategy to boost the photocatalytic activity of conjugated polymer photocatalysts, [15][16][17][18] since the intrinsic electron push-pull effect in a D-A conjugated polymer could promote the separation of light-induced hole/ electron. The nature of electron donor and acceptor units plays a key point in the charges transfer and separation, which affect significantly the photocatalytic activity. Therefore, the selection of electron donor and acceptor is of great importance for constructing organic polymer photocatalysts with high photocatalytic activity. In general, aromatic heterocyclic compounds with narrow band gap are commonly used as electron acceptors, and aromatic hydrocarbons with delocalized π-electron are employed as electron donors to build D-A type polymer photocatalysts. Based on the developed D-A polymer photo catalysts to date, [15,[19][20][21][22] dibenzo[b,d]thiophene-S,S-dioxide (BTDO) might be the most effective acceptor unit due to its strong electronwithdrawing capability and high hydrophilicity, [23][24][25] and pyrene with planar molecular structure and large delocalized π-electron system is the most effective electron donor to prepare high performance polymer photocatalysts. [26,27] Although there have been significant advances in the photo catalytic activity of polymer photocatalysts by structure optimization, [28,29] the limited scope of high efficient electron donors and acceptors hinders the further development of organic polymer photo catalysts. To further improve the photocatalytic activity and enrich the D-A) molecular structure show high photocatalytic activity for hydrogen evolution due to the efficient light-induced electron/hole separation, which is mostly determined by the nature of electron donor and acceptor units. Therefore, the selection of electron donor and acceptor holds the key point to construct high performance polymer photocatalysts. Herein, two dibenzo[b,d]thiophene-S,Sdioxide (BTDO) containing CMP photocatalysts using tetraphenylethylene (TPE) or dibenzo[g,p]chrysene (DBC) as the electron donor to investigate the influence of the geometry of electron donor on the photocatalytic activity are design and synthesized. Compared with the twisted TPE donor,...

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