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Biomimetic optical cellulose nanocrystal (CNC) materials have shown great potential for application in colorimetric sensing, anticounterfeiting, and decorative coatings because of simple recognitio...

In this work, a succession of Keggin-type polyoxometalate (POM)-based metal–bis(pyridyl-tetrazole) complexes, {Cu₂(3-bptzp)₃(H₂O)₄[SiW₁₂O₄₀]}·H₂O (1), {Cu₂(3-bptzpe)₂(H₂O)₈[SiW₁₂O₄₀]}·4H₂O (2), and {Cu₂(3-bptzh)₃(H₂O)₆[SiW₁₂O₄₀]} (3) (3-bptzp = 1,4-bis(5-(3-pyridyl)tetrazolyl)-butane; 3-bptzpe = 1,4-bis(5-(3-pyridyl)tetrazolyl)-pentane; 3-bptzh = 1,4-bis(5-(3-pyridyl)tetrazolyl)-hexane), were prepared and structurally characterized, which exhibited different architectures. The title complexes were used directly as electrocatalysts for hydrogen evolution reaction in alkaline and acidic media. The electrocatalytic activity for generating hydrogen was reinforced by the introduction of POMs. Complex 1 possesses the highest electrocatalytic activity for hydrogen evolution reaction with a low overpotential of 59.4 mV, achieving the current density of 10 mA·cm–² in 0.1 M KOH. The different structures of the title complexes showed effects on the hydrogen evolution performance. For 1, the insertion of POMs between the ordered 2D metal–organic layers induced the enhancement of electrocatalytic activity.

As one of the most important biobased and biodegradable polymers with a promising commercial prospect, polylactic acid (PLA) has gained increasing interest. Nevertheless, its high mechanical streng...

Silicon (Si) anodes display high specific capacity but mostly suffer from poor cycling ability owing to their dramatic volume expansion during the discharge/charge process. An effort was devoted to...

As one of the most efficient and environmentally benign strategies to treat organic dye pollution, TiO2 photocatalytic technology has attracted increasing and wide interests in environmental governance, for which dominantly exposed (001) facets and high porosity are of great importance for catalytic performance. To date, however, how to synergistically regulate the dominant growth of (001) facets and the formation of hierarchical pore structures still remains challenging. Here, we report a limited growth strategy mediated by the self-assembly of cellulose nanocrystal (CNC) to prepare anatase TiO2 nanocatalyst with dominantly exposed (001) reactive facets. Notably, crystal growth in the confined space of layered CNC structures favors exposing (001) facets, and the easy removal of the soft biotemplate facilitates creating hierarchical pores. Furthermore, the (001) facet percentage, pore size, and porosity can be easily modulated by controlling the CNC concentration. After introducing an up-conversion quantu...

Water collection from moisture and fog has been of particular interest to arid areas. To mimic the water-collecting capacity of Namib desert beetles, herein, we exploit a facile and low-cost approa...

For improving the thermal stability, glass transition temperature (Tg), stiffness, and hydrophilicity of poly(e-caprolactone) (PCL), two glucose-based bicyclic rigid structures, namely 1,4:3,6-dianhydrohexitols-D-glucidol (isosorbide, Is) and dimethyl 2,4:3,5-di-O-methylene-D-glucarate (glu-diester) have been introduced into PCL via chain extension. The two series of multiblock copolyesters obtained, PCL-b-PIS and PCL-b-PBG, have high number-average molecular weights in the range of 9.6 × 104 to 12.4 × 104 g mol–1 and small PDI values. The thermal and crystallization behaviors, hydrophilicity, as well as the mechanical properties of PCL-b-PIS and PCL-b-PBG have been well investigated. In comparison, the improved effect on thermal stability and Tg of PCL is more pronounced for PCL-b-PBG than for PCL-b-PIS. Both glucose-based units retard the crystallinity of PCL. However, the crystal structure and melting temperature of PCL remain unchanged. The rigidness of PCL is enhanced when glucose-based bicyclic unit...

Presently, flexible electromechanical sensors are of particular interest to next generation mobile applications. To enrich the flexible encapsulants, herein, a fully biobased film is developed by cross-linking soy protein isolate (SPI) with nanocross-linker, aldehyde-bearing, cellulose nanocrystals (CNC). Thanks to the enhanced interfacial interaction between SPI and CNC resulting from the Maillard reaction, the protein-rich phase becomes more homogeneous with smaller domain size. Compared with neat SPI film, the resultant composite films exhibit an obviously improved mechanical property and water resistance. In particular, the heat-sealing property of such films is well maintained, which guarantees their application as encapsulation layers to construct flexible electromechanical sensors. These results indicate that green composite films hold promising applications as universal encapsulation materials for integrating flexible movement-monitoring electronics.

The mesoporous structure and high exposure of the (001) facet are of great importance to the photocatalytic performance of TiO2. In this Letter, we report using cellulose nanocrystal (CNC) as a sacrificial template to develop mesoporous TiO2 with dominantly exposed (001) facets, for which CNC can provide confined space for the controlled crystal growth of TiO2 and create mesopores after being removed. Owing to the photoluminescence up-conversion, furthermore, carbon quantum dot (C-dot) is introduced to realize visible light catalytic property of TiO2. In particular, the TiO2/C-dot composite with an extremely low content of carbon dot exhibits high catalytic performance, for which the mechanism is discussed. These results indicate such biotemplating method offers the potential to develop more mesoporous nanomaterials with desirable structures.

In order to develop superhydrophobic and self-cleaning materials based on biomass, a simple and moderate method was used herein to grow Cu3(PO4)2·3H2O nanoflowers on the surface of soy protein isolate (SPI) film. Relying on the controllably hierarchical micro/nano-structures of the nanoflowers, the wetting behavior of resultant film can be tuned. The stability of the nanoflowers on an SPI surface was excellent because of the coordination interaction between SPI and copper ions. In particular, the superhydrophobic surface can resist moderate acid and base without losing the antiwetting property. Furthermore, a self-cleaning function was achieved for the SPI film fully covered with the nanoflowers. Such biobased film will be of great interest to biomedical and industrial applications.

Construction of novel multishape memory materials from biobased polymers is of particular interest in recent years. Herein, a series of linear poly(lactic acid) (PLA)-based copolymers containing a smectic liquid crystal in the main-chain are designed and synthesized, of which the molecular structures are confirmed by NMR and GPC analyses. By introducing the liquid crystal, poly[4,4′-bis(6-hydroxyhexyloxy) biphenyl phenylsuccinate] (PBDPS), the brittleness of PLA is overcome, and flexible materials are successfully prepared. Relying on the crystallization of PLA as well as the π–π interaction that originated from PBDPS, the copolymers exhibit excellent thermoinduced triple- and quadruple-shape memory behaviors with high shape fixation and recovery ratios. Taking advantage of these features, the multishape memory polymers can bring more chances for versatile applications.

In order to improve the mechanical and oxygen barrier properties of poly(butylene succinate) (PBS), two series of sugar-containing PBS copolyesters with different molecular stiffness were synthesized and comparatively investigated, in which a cyclic alditol, isosorbide (Is) or 2,3-O-isopropylidene-l-threitol (ITh) was, respectively, used as a comonomer. Both cyclic alditols were easily available from biomass feedstock, such that Is is a bicyclic compound derived from d-glucose, and ITh is a monocyclic acetalized compound coming from naturally occurring l-tartaric acid. All these copolyesters containing up to 30 mol % of sugar-based units had satisfactory number-average molecular weights in the 16 000–83 000 g mol–1 range, and presented a random microstructure together with excellent thermal stability. The sugar-containing copolyesters were all semicrystalline and still possessed the monoclinic crystal structure of PBS. The incorporation of either Is or ITh units with rigid cyclic structure into PBS chain ...