The significant drawbacks and lack of success associated with current methods to treat critically sized nerve defects have led to increased interest in neural tissue engineering. Conducting polymers show great promise due to their electrical properties, and in the case of polypyrrole (PPY), its cell compatibility as well. Thus, the goal of this study is to synthesize a conducting composite nerve conduit with PPY and poly(D, L-lactic acid) (PDLLA), assess its ability to support the differentiation of rat pheochromocytoma 12 (PC12) cells in vitro, and determine its ability to promote nerve regeneration in vivo. Different amounts of PPY (5%, 10%, and 15%) are used to synthesize the conduits resulting in different conductivities (5.65, 10.40, and 15.56 ms/cm, respectively). When PC12 cells are seeded on these conduits and stimulated with 100 mV for 2 h, there is a marked increase in both the percentage of neurite-bearing cells and the median neurite length as the content of PPY increased. More importantly, when the PPY/PDLLA nerve conduit was used to repair a rat sciatic nerve defect it performed similarly to the gold standard autologous graft. These promising results illustrate the potential that this PPY/PDLLA conducting composite conduit has for neural tissue engineering.

Transformation of carbon dioxide to high value‐added chemicals becomes a significant challenge for clean energy studies. Here a stable and conductive covalent organic framework was developed for electrocatalytic carbon dioxide reduction to carbon monoxide in aqueous solution. The cobalt(II) phthalocyanine catalysts are topologically connected via robust phenazine linkage into a two‐dimensional tetragonal framework that is stable under boiling water, acid, or base conditions. The 2D lattice enables full π conjugation along x and y directions as well as π conduction along the z axis across the π columns. With these structural features, the electrocatalytic framework exhibits a faradaic efficiency of 96 %, an exceptional turnover number up to 320 000, and a long‐term turnover frequency of 11 412 hour−1, which is a 32‐fold improvement over molecular catalyst. The combination of catalytic activity, selectivity, efficiency, and durability is desirable for clean energy production.

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A new kind of piperazine-linked covalent organic framework (COF) was synthesized through the nucleophilic substitution reaction between octaminophthalocyanines and hexadecafluorophthalocyanines. The two-dimensional (2D) frameworks are in tetragonally shaped polygon sheets, which stack in an AA stacking mode to constitute periodically ordered metallophthalocyanine columns and one-dimensional (1D) microporous channels. The piperazine-linked COFs exhibit excellent chemical stability and permanent porosity. By virtue of the neatly arrayed phthalocyanine columns and inbuilt cationic radicals, the piperazine-linked frameworks are highly conductive. The conductivity values of NiPc-NH-CoPcF8 COF reached up to 2.72 and 12.7 S m–1 for pellet and film samples, respectively. Moreover, this p-type conductive COF exhibited a high carrier mobility of 35.4 cm2 V–1 s–1. Both the electric conductivity and carrier mobility set new records for conductive COFs.

The development of highly stable covalent organic frameworks (COFs) is extremely compelling for their implementation in practical application. In this work, we rationally designed and synthesized new kinds of ultrastable bimetallic polyphthalocyanine COFs, which are constructed with the dioxin linkage through the nucleophilic aromatic substitution between octahydroxyl­phthalocyanine and hexadecafluoro­phthalocyanine. The resulting bimetallic CuPcF8-CoPc-COF and CuPcF8-CoNPc-COF exhibited strong robustness under harsh conditions. The eclipsed stacking mode of metallo­phthalocyanine units supplies a high-speed pathway for electron transfer. With these structural advantages, both COFs displayed considerable activity, selectivity, and stability toward electrocatalytic CO2 reduction in an aqueous system. Notably, CuPcF8-CoNPc-COF showed a faradaic efficiency of 97% and an exceptionally high turnover frequency of 2.87 s–1, which is superior to most COF-based electrocatalysts. Furthermore, the catalytic mechanism was well demonstrated by using a theoretical calculation. This work not only expanded the variety of dioxin-linked COFs, but also constituted a new step toward their practical use in carbon cycle.

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Lignocellulosic biomass is considered as one of the most promising feedstocks for producing fuel ethanol because of its global availability and environmental benefits of its use. In this paper, the process of lignocellulosic ethanol production was investigated at its present state of development. The experimental data from the East China University of Science and Technology were used to develop a process model and evaluate the performance of the whole process design. For the process simulation, all relevant information about the process streams, physical properties, and mass and energy balances were also considered. Energy integration is investigated to identify the best ways to supply heat to the process, realizing also combined heat and power production from wastewater and residue treatment. The sensitivity on ethanol yield and the overall system performance are also investigated.

A facile and bioinspired synthesis of ZnO hierarchical architectures, including prismlike and flowerlike structures and crytalline and noncrystalline hollow microspheres, has been developed using the amino acid histidine as the directing and assembling agent. The histidine molecules play different roles in the formation of ZnO hierarchical architectures due to the competitive coordination between histidine and OHto Zn 2+ when the reactant molar ratios are adjusted. The resulting architectures are characterized using field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectoscopy, and thermogravimetric analysis (TGA). Morphology-and phase-dependent photoluminescence of the ZnO architectures has been shown. In particularly, a novel photocatalytic activity of the ZnO hierarchical architectures for the reaction of the formaldehyde and carbon dioxide has been demonstrated, probably through mechanisms involving an oxidative coupling reaction and hydrolyzation process.