It is a challenge to regulate charge flow synergistically at the atomic level to modulate gradient hydrogen migration (H migration) for boosting photocatalytic hydrogen evolution. Herein, a self-adapting S vacancy (Vs) induced with atomic Cu introduction into ZnIn 2 S 4 nanosheets was fabricated elaborately, which can tune charge separation and construct a gradient channel for H migration. Detailed experimental results and theoretical simulations uncover the behavior mechanism of Vs generation with Cu introduction after substituting a Zn atom tendentiously. Cu−S bond shrinkage and Zn−S bond distortion are presented around Vs areas. Besides, Vs induced by Cu introduction lowers the internal electric field to restrain electron transmission between layers, which are enriched on the Vs area because of the lower surface electrostatic potential. Atomic Cu and Vs show a synergistic effect for regulating regional charge separation due to the Cu dopant being a hole trap and Vs being an electron trap. The channels for H migration with gradient ΔG H 0 are constructed by different S atom sites, which are modulated by Vs. Gradient H migration driven by a photothermal effect occurs on an identical surface without striding across a heterogeneous interface, which is a valid pathway with lower resistance for boosting H 2 release. Ultimately, 5 mol % Cu confined in ZnIn 2 S 4 nanosheets achieves an optimum photocatalytic hydrogen evolution activity of 9.8647 mmol g −1 h −1 , which is 14.8 times higher than 0.6640 mmol g −1 h −1 for ZnIn 2 S 4 , and apparent quantum efficiency reaches 37.11% at 420 nm. This work demonstrates the behavior mechanism of atomic substitution and provides cognition for hydrogen evolution mechanism deeply.

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Despite the existence of numerous photocatalyst heterostructures, their separation efficiency and charge flow precision remain low due to the poor study on interfacial properties. The photocatalysts with confined defects can effectively control the photogenerated carrier migration, but the metastability of such defects considerably decreases the photocatalyst stability. Meanwhile, the introduction of defective region can increase the coordinative unsaturation and delocalize local electrons to promote their interactions with the molecules/ions in that region. The selective growth of modulated heterogeneous interface by defect‐induced strategy may not only increase the stability of defective structures, but also enhance the migration of interfacial charges. Using this method, photocatalytic heterostructures with low contact resistances and intimate interfaces are constructed to achieve the optimal charge migration in terms of efficiency and accuracy. In this work, the point, linear, and planar heterogeneous interfaces and related defect engineering techniques are discussed. Particularly, it is focused on the external, defect‐induced interfacial heterogeneities with various spatial and dimensional configurations, which exhibit modulated and controllable interfacial properties. Furthermore, the main aspects of fabricating photocatalyst heterostructures by the defect‐induced strategy, including the i) controllable generation of defects, ii) advanced characterization methods, and iii) elaborate construction of the minimal interface, are described.

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Carbon quantum dots/CdS quantum dots/g-C3N4 (CDs/CdS/GCN) photocatalysts have been designed and prepared. Systematic characterization such as XRD, SEM, TEM, UV, and XPS, were done to confirm the composite catalysts of CDs/CdS/GCN. The simultaneous photocatalytic production of hydrogen coupled with degradation of organic contaminants (p-chlorophenol, bisphenol A, and tetracycline, called 4-NP, BPA, and TTC, respectively) was efficiently realized over the resultant CDs/CdS/GCN composites. The as-prepared 3%CDs/10%CdS/GCN exhibits high efficiency of photocatalytic hydrogen evolution from water splitting and photodegradation rates of organic pollutants in aqueous solutions of 4-NP, BPA, and TTC under visible-light illumination since the formation of interfaces between CdS quantum dots and GCN nanosheets leads to an efficient charge separation efficiency. Furthermore, as compared to that in a pure water system, the photocatalytic evolution rate of H2 over the 3%CDs/10%CdS/GCN catalyst in the presence of 4-NP solution is decreased, while the H2 evolution rates increase when BPA or TTC solution were used instead of 4-NP solution under visible-light irradiation. Consequently, 4-NP shows higher photodegradation efficiency than do BPA and TTC in the simultaneous photocatalytic oxidation and reduction system. Aiming at making clear the relationship between the photocatalytic H2 production and the photocatalytic pollutants degradation, density functional theory (DFT) calculations, and liquid chromatography mass spectrometry (LC-MS) were used for a systematic investigation. The present work reports a plausible mechanism of photodegradation of different organic contaminants with synchronous photocatalytic H2 evolution from water and the photocatalytic enhancement of the CDs/10%CdS/GCN catalysts.

Hydroxyl ionic liquid grafted onto cross-linked divinylbenzene polymer (PDVB-HEIMBr) was fabricated and evaluated as a catalyst for the synthesis of cyclic carbonates from CO 2 and epoxides without the use of any cocatalyst and organic solvent. The catalyst shows good performance across a wide range of epoxides, giving almost quantitative yield of carbonates (140°C, 2.0 MPa of initial CO 2 , and B4 h). The effects of reaction temperature, time and initial CO 2 pressure on product yield were investigated. It is suggested that the synergetic effect between the bromide ions and the hydroxyl groups facilitates the coupling reaction. Furthermore, the PDVBHEIMBr catalyst shows excellent stability and reusability. From the viewpoint of industrial application, the catalyst is very attractive because of its simplicity, activity, stability, and reusability.

The adsorption of iodine by porous organic polymers is an active research topic. Here, we synthesized three porous organic polymers, TTDP-1, TTDP-2, and TTDP-3, to study the adsorption of iodine. A suitable configuration for iodine adsorption was identified by flexibly adjusting the stacking degree of aldehyde monomers to change the porosity of the porous organic polymer. The adsorption power of TTDP-1, TTDP-2, and TTDP-3 to iodine can reach 536, 470, and 425 wt %, respectively. All exhibit good adsorption capacity. By studying the thermogravimetric and infrared spectra of the TTDP-X material before and after iodine adsorption, we proved that iodine can form a charge transfer complex between the aromatic skeleton connected by the imine bond. This combination can increase iodine adsorption.