Disposal and recycling of the large scale biomass waste is of great concern. Themochemically converting the waste biomass to functional carbon nanomaterials and bio-oil is an environmentally friendly apporach by reducing greenhouse gas emissions and air pollution caused by open burning. In this work, we reported a scalable, "green" method for the synthesis of the nanofibers/mesoporous carbon composites through pyrolysis of the Fe(III)-preloaded biomass, which is controllable by adjustment of temperature and additive of catalyst. It is found that the coupled catalytic action of both Fe and Cl species is able to effectively catalyze the growth of the carbon nanofibers on the mesoporous carbon and form magnetic nanofibers/mesoporous carbon composites (M-NMCCs). The mechanism for the growth of the nanofibers is proposed as an in situ vapor deposition process, and confirmed by the XRD and SEM results. M-NMCCs can be directly used as electrode materials for electrochemical energy storage without further separation, and exhibit favorable energy storage performance with high EDLC capacitance, good retention capability, and excellent stability and durability (more than 98% capacitance retention after 10,000 cycles). Considering that biomass is a naturally abundant and renewable resource (over billions tons biomass produced every year globally) and pyrolysis is a proven technique, M-NMCCs can be easily produced at large scale and become a sustainable and reliable resource for clean energy storage.

Circularly polarized luminescence (CPL) has gained considerable attention in various systems and has rapidly developed into an emerging research field. To meet the needs of actual applications in diverse fields, a high luminescence dissymmetry factor (g lum ) and tunable optical performance of CPL would be the most urgent pursuit for researchers. Accordingly, many emerging CPL materials and various strategies have been developed to address these critical issues. Emissive cholesteric liquid crystals (CLCs), that is, luminescent self-organized helical superstructures, are considered to be ideal candidates for constructing CPL-active materials, as they not only exhibit high g lum values, but also enable flexible optical control of CPL. This review mainly summarizes the characteristics of CPL based on CLCs as the bulk phase doped with different emitters, including aggregated induced emission molecules, conventional organic small molecules, polymer emitters, metal-organic complex emitters, and luminescent nanoparticles. In addition, the recent significant progress in stimulus-responsive CPL based on emissive CLCs in terms of several types of stimuli, including light, electricity, temperature, mechanical force, and multiple stimuli is presented. Finally, a short perspective on the opportunities and challenges associated with CPL-active materials based on the CLC field is provided. This review is anticipated to offer new insights and guidelines for developing CLC-based CPL-active materials for broader applications.

In this work, we investigated the anaerobic decolorization of methyl orange (MO), a typical azo dye, by Shewanella oneidensis MR-1, which can use various organic and inorganic substances as its electron acceptor in natural and engineered environments. S. oneidensis MR-1 was found to be able to obtain energy for growth through anaerobic respiration accompanied with dissimilatory azo-reduction of MO. Chemical analysis shows that MO reduction occurred via the cleavage of azo bond. Block of Mtr respiratory pathway, a transmembrane electron transport chain, resulted in a reduction of decolorization rate by 80%, compared to the wild type. Knockout of cymA resulted in a substantial loss of its azo-reduction ability, indicating that CymA is a key c-type cytochrome in the electron transfer chain to MO. Thus, the MtrA-MtrB-MtrC respiratory pathway is proposed to be mainly responsible for the anaerobic decolorization of azo dyes such as MO by S. oneidensis.

Two light‐driven chiral fluorescent molecular switches, (R,S,R)‐switch 1 and (R,S,R)‐switch 2, are prepared by means of hydrogen‐bonded (H‐bonded) assembly of a photoresponsive (S) chiral fluorescent molecule, respectively with a cyano substitution at different positions as an H‐bond acceptor and an opposite (R) chiral molecule as an H‐bond donor. The resulting two switches exhibit tunable and reversible Z/E photoisomerization irradiated with 450 nm blue and 365 nm UV light. When doped into an achiral liquid crystal, both switches are found to be able to form a CPL tunable luminescent helical superstructure. In contrast to the tunable CPL characteristics of the system incorporating switch 2, exposure of the system incorporating switch 1 to 365 nm and 450 nm radiation can lead to controllable different photostationary CPL behavior, including switching‐off and polarization inversion. In addition, optical information coding is demonstrated using the system containing switch 1.

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Advanced encryption/decryption strategies are of great significance for information protection and data security. It is highly desirable yet quite challenging to develop functional materials for encrypting/decrypting information more effectively. Herein, a novel emissive liquid crystal elastomer (LCE) for multidimensional and multistage encryption is proposed for the first time, through synergistic utilization of phototunable fluorescence and the photoprogrammable shape. The fluorescent LCE is fabricated by incorporating an aggregation-induced-emission α-cyanodiarylethene-based hydrogen-bonded complex and azobenzene derivative into the LCE networks through covalent bonding. Because of the photoisomerization of both these two photosensitive derivatives under the same exciting light, the consequent LCE films exhibit photoinduced reversible fluorescence changes and shape deformations that are suitable for data storage and encryption. On this basis, the collaborative usage of photolithography-based 2D fluorescent images and photoprogramming 3D shape configurations can lead to multidimensional and multistage encryption. Moreover, this encryption strategy is reprogrammable, allowing for repeatable encoding and decrypting. The results demonstrated here reveal that the reversible phototunable fluorescent LCE materials exhibit promising applications in data storage and encryption.

The efficiency of a microbial fuel cell (MFC) generally suffers from its poor cathode performance. To improve this, a novel cathode material was prepared by growing vertically aligned nitrogen-doped carbon nanotubes on carbon cloth, offering an efficient, metal-free, and low-cost alternative to Pt/C.