Conjugated porous polymers (CPPs) have recently emerged as prospective materials for photocatalytic hydrogen evolution. In the design of CPP photocatalysts, one of the challenges is to find ways to inhibit backward charge recombination and promote forward charge transfer/separation. Conjugated donor–acceptor polymers are capable of favoring forward intramolecular charge separation; however, they often suffer from backward charge recombination simultaneously, which causes a decrease of the quantum efficiency for solar-energy conversion. Herein, a photoinduced electron-transfer system via constructing D–A1–A2 conjugated polymers for photocatalytic hydrogen evolution is developed. Such a D–A1–A2 system can not only boost charge separation but also suppress charge recombination owing to the cascade energy levels of the comprised units and large charge delocalization structures. Therefore, an apparent quantum yield up to 22.8% at 420 nm is achieved, and the highest hydrogen evolution rate can be up to 966 μmol h–1 (19.3 mmol g–1 h–1) under visible light irradiation. These values are comparable to the state-of-the-art CPPs as well as part of inorganic photocatalysts. This work provides an alternative strategy and insight for the design of CPP photocatalytic systems for photocatalytic applications in high efficiency.

Engineering heteroatoms that precisely positioned in covalent triazine frameworks (CTFs) can dramatically enhance the photocatalytic hydrogen evolution rate of CTFs and is thus an effective strategy to improve the photocatalysis performance for porous organic polymers (POPs).

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The structural characteristics of hyper-cross-linked polymers (HCPs) make them interesting for a wide variety of applications.

The development of cost-effective, functional materials that can be efficiently used for sustainable energy generation is highly desirable. Herein, a new molecular precursor of bismuth (tris(selenobenzoato)bismuth(III), [Bi(SeOCPh) 3 ]), has been used to prepare selectively Bi or Bi 2 Se 3 nanosheets via a colloidal route by the judicious control of the reaction parameters. The Bi formation mechanism was investigated, and it was observed that the trioctylphosphine (TOP) plays a crucial role in the formation of Bi. Employing the vapor deposition method resulted in the formation of exclusively Bi 2 Se 3 films at different temperatures. The synthesized nanomaterials and films were characterized by p-XRD, TEM, Raman, SEM, EDX, AFM, XPS, and UV–vis spectroscopy. A minimum sheet thickness of 3.6 nm (i.e., a thickness of 8–9 layers) was observed for bismuth, whereas a thickness of 4 nm (i.e., a thickness of 4 layers) was observed for Bi 2 Se 3 nanosheets. XPS showed surface oxidation of both materials and indicated an uncapped surface of Bi, whereas Bi 2 Se 3 had a capping layer of oleylamine, resulting in reduced surface oxidation. The potential of Bi and Bi 2 Se 3 nanosheets was tested for overall water-splitting application. The OER and HER catalytic performances of Bi 2 Se 3 indicate overpotentials of 385 mV at 10 mA cm –2 and 220 mV, with Tafel slopes of 122 and 178 mV dec –1 , respectively. In comparison, Bi showed a much lower OER activity (506 mV at 10 mA cm –2 ) but a slightly better HER (214 mV at 10 mA cm –2 ) performance. Similarly, Bi 2 Se 3 nanosheets were observed to exhibit cathodic photocurrent in photoelectrocatalytic activity, which indicated their p-type behavior.

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Porous carbon materials prepared from the porous organic polymers are currently the subject of extensive investigation. On the basis of their interesting applications, it is highly desirable to develop new synthetic methodologies to obtain carbon materials with controllable pore size and morphology. Herein, a facile synthesis of hollow microporous carbon spheres (HCSs) from hollow microporous organic capsules (HMOCs) with a good control over the pore morphology, hollow cavity, and the shell thickness is reported. The highly porous hollow carbon spheres are prepared by the pyrolysis of HMOCs-based microporous polymers. The synthetic parameters, such as hypercrosslinking and pyrolysis conditions, are optimized to modify the porous structures and the properties. The morphology and porosity as well as energy storage applications of the microporous structures HCSs, derived through a combination of divinylbenzene-crosslinking and micropore-generating hypercrosslinking, are discussed. These findings provide a new benchmark for fabricating well-defined HCSs with great promise for various applications.

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