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Herein, a low‐temperature sublimation‐based vapor deposition (SVD) method is developed to synthesize hexagonal crystal plates of cyanuric acid‐melamine (CAM) with outstanding crystallinity. Through meticulous design of the reaction apparatus and careful selection of source materials, substrate‐confined SVD in a tube furnace is explored to grow single crystals of CAM in hexagonal shapes. Additionally, the orientation preference of the (202) facet is revealed, corresponding to the 2D arrangement of the H‐bonded network, of single‐crystalline plates on surfaces using selected area electron diffraction and X‐ray diffraction techniques. By employing atomic force microscopy and scanning electron microscopy for topography characterization, a mechanism of three‐stage step‐growth crystallization is proposed, including nucleation, in‐plane expansion, and out‐of‐plane growth. Furthermore, it is found that the interactions among melamine molecules in CAM synthesized via SVD are more intense compared to those in CAM synthesized via water‐based methods, as evidenced by infrared and photoluminescent spectra studies. Subsequent nanoindentation tests on the (202) facet of CAM single‐crystalline plates reveals a reduced modulus and hardness of 12.8 and 0.82 GPa, respectively. This methodology addresses the longstanding challenge of synthesizing hexagonal CAM single crystals and provides valuable insights for the fabrication of functional organic crystalline materials. [ABSTRACT FROM AUTHOR]

Biomass with abundant reproducible carbon resource holds great promise as an intriguing substitute for fossil fuels in the manufacture of high‐value‐added chemicals and fuels. Photocatalytic biomass valorization using inexhaustible solar energy enables to accurately break desired chemical bonds or selectively functionalize particular groups, thus emerging as an extremely creative and low carbon cost strategy for relieving the dilemma of the global energy. Quantum dots (QDs) are an outstandingly dynamic class of semiconductor photocatalysts because of their unique properties, which have achieved significant successes in various photocatalytic applications including biomass valorization. In this review, the current development rational design for QDs photocatalytic biomass valorization effectively is highlighted, focusing on the principles of tuning their particle size, structure, and surface properties, with special emphasis on the effect of the ligands for selectively broken chemical bonds (C─O, C─C) of biomass. Finally, the present issues and possibilities within that exciting field are described. [ABSTRACT FROM AUTHOR]

With the increase in water consumption and pollution resulting from the rising world population and industrial development, severe fresh water shortage has been regarded as one of the critical problems facing the world. Solar‐driven water purification is an environment friendly and promising technology to address the problem. However, low photothermal conversion efficiency impedes its practical application. Herein, a natural spruce wood‐based solar evaporator functionalized with zeolitic imidazolate framework (ZIF‐8) nanoparticles and polydopamine (PDA) layers is designed, which significantly reduces the equivalent evaporation enthalpy and substantially boosts solar evaporation efficiency. The evaporation rate of the optimized wood‐based evaporator reached 2.28 kg m−2 h−1 with a high evaporation efficiency of 87.5% under 1.0 sun. Furthermore, the integrated spruce wood/ZIF‐8/PDA hybrids can remove organic pollutants after solar evaporation. Notably, the constructed multifunctional solar evaporator takes advantage of sustainable solar energy, low‐cost biomass, and ZIF‐8/PDA nanostructures to acquire desirable performance in water evaporation and sewage purification. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are regarded as one of the most prominent future‐oriented energy battery systems due to their high theoretical energy density (2600 Wh kg−1). However, the shuttle effect of polysulfides and short cycle life have critically hindered their commercialization. Herein, a stepped porous heterostructured membrane of carbon‐multilayer graphene (MG)@Fe3C/Fe3N is developed by a facile phase inversion method and applied as a current collector to replace Al foil. The special heterostructured membrane with MG can further boost the charge/Li+ ion transfer speed while accommodating the volume expansion in the charge/discharge cycle. The shuttle effect of polysulfides is inhibited by the heterostructure phase of the Fe3C/Fe3N catalytic effect and chemisorption. This synergistic effect is confirmed by density function theory (DFT) calculations. As a result, the C‐MG@Fe3C/Fe3N membranes delivers distinguished discharge capacity and cycling stability of 508.92 mAh g−1 (693.47 mAh g−1) at a large discharge of current of 2 C (at 0.5 C) after 400 cycles (300 cycles) with only 0.36% capacity attenuation per cycle. [ABSTRACT FROM AUTHOR]

Solar-driven chemical processes are promising alternatives to conventional chemical production, especially considering the global challenges faced by humans, such as energy shortage, environmental pollution and global warming. Designing and constructing high-performance semiconductor photocatalysts with broad light absorption, matching band positions, fast carrier transfer, and sufficient active sites are highly desired but also challenging. Since bulk photocatalytic materials generally suffer from rapid carrier recombination due to their large physical dimensions, fabricating nanometer-sized photocatalytic materials is regarded as an effective strategy to shorten the carrier migration distance, thereby encouraging more carriers to be involved in photocatalytic reactions before recombination. 2D ultrathin materials are an important family of photocatalysts due to their large lateral dimension/thickness ratio. The goal of this review is to summarize the latest progress in 2D ultrathin materials from a green synthesis perspective, involving specific synthetic strategies and approaches. The discussed 2D materials include bismuth oxyhalides (BixOyXz), carbon nitrides (C3N4), conjugated covalent organic frameworks (COFs), and metal–organic frameworks (MOFs). [ABSTRACT FROM AUTHOR]