Hydrogen production through solar energy is one of the most important pathways to meet the growing demand of renewable energy, and photocatalyst participation in solar hydrolytic hydrogen production has received great attention in recent years in terms of low cost, high efficiency, and flexible design. Particularly, g-C 3 N 4 (Graphiticlike carbon nitride material), as a unique material, can catalyze the hydrogen production process by completing the separation and transmission of charge. The easily adjustable pore structure/surface area, dimension, band-gap modulation and defect have shown great potential for hydrogen production from water cracking. In this review, the most recent advance of g-C 3 N 4 including the doping of metal and non-metal elements, and the formation of semiconductor heterojunction is highlighted. The main modification strategies and approaches for the design of g-C 3 N 4 for hydrogen production, as well as the influence of various materials on hydrogen evolution regarding the photocatalysis mechanism and advantages brought by theoretical calculations are specially and briefly illustrated. Potential design pathways and strategies of g-C 3 N 4 are discussed. In addition, current challenges of hydrogen production from g-C 3 N 4 water splitting are summarized and can be expected.

The cardanol-based phthalonitrile (PN) monomer was successfully produced via the nucleophilic substitution reaction of cardanol with 4-nitrophthalonitrile in potassium carbonate media. The conventional methods were employed to predict the chemical structure. The influence of long alkyl chains of cardanol was observed on the thermomechanical properties, recorded values were much below than the poly(Baph) standards. However, the thermal stabilities were recorded in good agreement to PN resin values. Furthermore, the 100 kGy dose of Co 60 irradiation does not show any remarkable changes in the studied properties. The copolymers from P-a benzoxazine and cardanol-based PN (CPN) on the different wt % blending were prepared. The curing behavior and mechanism of the monomer blends were analyzed. The curing of CPN was improved in the presence of active hydrogen produced from the P-a polymerization. The T g and thermal properties of the copolymer were much better than the neat poly(P-a).

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In the current study, three different curing kinetics models were used to analyze the curing kinetics of hyperbranched benzoxazine (HB‐PED230) and monofunctional benzoxazine (P‐a) modified cyanate ester (CE) resin by non‐isothermal differential scanning calorimeter. Moreover, the effects of two benzoxazines on the copolymerization behavior, thermal stability, and mechanical properties of CE resin were studied. Compared with the P‐a modified CE resin, HB‐PED230 greatly reduces the curing temperature of the copolymer, while improving the bending strength and impact strength. The curing temperature of HB‐PED230 modified CE resin was 79°C lower than neat CE resin, while the CE/P‐a blended resin only reduce 48°C. As the amount of HB‐PED230 increased, the flexural strength and flexural modulus of the copolymers were improved. Surprisingly, when 7 wt% of HB‐PED230 was added, the impact strength of the copolymer was increased by 177.6%, implying that the toughness of CE resin had been greatly improved. Moreover, the fracture morphology of the copolymers was observed by scanning electron microscope. In summary, a small amount of HB‐PED230 blending can effectively improve the overall performance of CE resin.

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With the increase of global proportion of soil pollution and the number of areas at risk, researchers have sought to develop various pathways to repair or relieve the pollutants in soil. Among them, biochar represents one multidimensional soil amendment which has got great deal of attention on its physicochemical properties towards the removal or mitigation of contaminants in soil. A variety of agricultural wastes like straw and manure prepared from different torrefaction process have been employed as feedstock for the production of biochar, which can be applied to the contaminated soil to facilitate the growing environment for crops, and to improve soil fertility and microbial environment. In addition, the utilization of biochar for soil remediation is also considered as a process of carbon sequestration. The purpose of this review is to summarize the latest research progress in torrefaction processes and mechanism of agricultural waste, the effects of different torrefaction methods on the formation and properties of biochar were explained, coupled with the effects of process parameters. Especially, the conversion and mechanisms of biochar prepared from agricultural wastes composed mainly with lignocellulosic material were discussed, and the characteristics of biochar prepared for improving soil physical and chemical characteristics, microbial community characteristics, nutrients, and the stability and relief of soil pollutants, especially heavy metals, are compared. Finally, this work discussed the application and future technical challenges of soil remediation based on agricultural waste derived biochar.