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Based on a new designed acyl hydrazone gelator (G2), we developed an efficient energy transfer supramolecular organogel in glycol with two different hydrophobic fluorescent dyes rhodamine B (RhB) and acridine...

Although excellent photocatalytic activity of donor–acceptor (D–A) polymers has been widely proved, different D/A ratios in the polymer skeleton affect their electronic properties and microstructure, which may limit their photocatalytic activity. To understand the relationship between the D/A ratio and photocatalytic activity, in this paper, a series of random conjugated polymers were synthesized by adjusting the molar ratio of D/A using pyrene as the electron D unit and dibenzothiophene sulfone as the electron A unit and applied to the study of photocatalytic hydrogen evolution from water reduction. When the molar ratio of D/A was 1:20, the PySO-2 polymer showed the highest photocatalytic hydrogen production activity of 23.3 mmol g–1 h–1, which was probably caused by the increase of the photo-induced carrier separation efficiency, indicating that the photocatalytic performance depended on the molar ratio of D/A in the skeleton. In addition, the hydrogen evolution rate (HER) of PySO-2 was nearly two times higher than that of PySO-6 under the same reaction conditions, suggesting that the photocatalytic performance relies on the molar ratio of D/A in the skeleton. All results indicate that adjusting the molar ratio of D/A in the polymer skeleton can influence the separation and migration efficiency of photogenerated charge carriers, which in turn accelerates the performance of photocatalytic hydrogen production.

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The presence of humic acid (HA) in water poses environmental problems because it enhances the transport of several contaminants. A series of column experiments was conducted toward studying HA transport in different porous media under various pH, ionic strength, and flow rate conditions. The results showed that decreasing pH and increasing ionic strength increased adsorption and therefore delayed the transport of HA in porous media. However, increasing flow rate accelerated the transport of HA in porous media. The effects of pH, ionic strength, and flow rate varied with the solid matrix and were more evident in sands of smaller average particle diameter than in those with larger ones. These factors must be considered when predicting the environmental fate of HA. The results also suggested that HA adsorption was an important process controlling HA transport and should be considered in studies of HA behavior in porous media.