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Graphitic carbon nitride (g-C 3 N 4 ) nanotubes were produced by using salicylic acid-mediated melamine successfully. The obtained long g-C 3 N 4 nanotube possesses a large specific surface area and a parallel channel structure. Salicylic acid and its decomposition products present in g-C 3 N 4 influenced its formation process and inhibited the crystal growth of g-C 3 N 4 . A possible mechanism is proposed: Salicylic acid and its decomposition products facilitated the formation of g-C 3 N 4 nanosheet, and then the nanosheet coiled to form a nanotube. The tube-like structure facilitates the increase in photocatalytic activities, which are 6.7 and 2.4 times that of pristine g-C 3 N 4 in 2-propanol decomposition and CO 2 photoreduction, respectively. The enhanced photocatalytic performance was contributed by the large specific surface area, better photogenerated charge carrier transmission, and the porous nanotube structure. This research provides an easy synthetic method for the large-scale production of g-C 3 N 4 nanotubes applied in the photocatalytic field.

Due to the COVID-19 outbreak, an online inorganic chemistry course for engineering students was set up at Zhejiang University for the 2020 spring semester. In this study, we will be using this course as an example of how to offer efficient methods for online teaching in chemistry. Applications such as DingTalk, WeChat, and the Learning@ZJU Web site were combined to establish a network platform to smoothly carry out this course. Personal insights on high-quality online teaching for inorganic chemistry are also discussed. Taken into consideration for online teaching and learning attributes, special screening background, scientific story and history, research frontiers, and interesting activities were incorporated to attract the attention of students in class. Study has found that these students performed very well in their two examinations, which confirmed that our established online platform and strategies are highly effective for teaching and learning.

Due to their ease of preparation, low cost and environmentally-friendly characteristics, zinc-type photocatalysts have attracted a lot of interest with regards to the photocatalytic degradation of organic pollutants. In this study, K+ doped ZnO (KZO) microcrystals were prepared from zinc acetate dehydrate and potassium hydroxide. X-ray diffraction analysis revealed the structure of the hexagonal wurtzite and the substitution of potassium ions in zinc oxide. A scanning electron microscope image showed the nanorod microstructure of prepared KZO crystallites. UV–visible analysis showed that the light absorption of KZO crystals expanded to the visible region and possessed a narrower band gap. In addition, the photocatalytic performance of KZO nanoparticles was evaluated. The results show that KZO possesses enhanced activity which is 3.45 times that of pure ZnO. This high performance in the photocatalytic degradation of organic pollutants can be ascribed to the band gap reduction, large surface area and improved transmission of charge carriers.

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Effectively reducing the concentration of CO 2 in ambient air is essential to mitigate global warming. Existing carbon capture and storage technology can only slow down the carbon emissions of large point sources but cannot treat the already accumulated CO 2 in the environment. Herein, we demonstrated a simple direct CO 2 capture method from air via reactive crystallization with a new trichelating iminoguanidine ligand (BTIG). It could strongly bind CO 2 to form insoluble carbonate crystals that could be easily isolated. In the crystal, CO 2 was transformed to CO 3 2– and trapped in a dense hydrogen bonding network in terms of carbonate–water clusters. This capture process was reversible, and the BTIG ligand could be regenerated by heating the BTIG–CO 2 crystal at a mild temperature, which was much lower than the decomposition temperature of CaCO 3 (∼900 °C). Thermodynamic and kinetics analyses indicate that the crystallization process was exothermic with an enthalpy of −292 kJ/mol, and the decomposition energy consumption was 169 kJ per mol CO 2 . In addition, BTIG could also be employed for CO 2 capture from flue gas with a capacity of 1.46 mol/mol, which was superior to that of most of the reported sorbents.