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Lithium sulfur batteries (LSBs) are regarded as one of the most promising energy storage devices because of their ultrahigh theoretical energy densities (2500 Wh kg-1), low cost, and environmental friendliness. Nevertheless, several detrimental drawbacks, including shuttling effects caused by soluble lithium polysulfides (LiPS), sluggish conversion kinetics between LiPS, and poor conductivities of sulfur, prevent commercialization of LSBs. To takle the above issues, MOF-derived cobalt disulfide/nitrogen-doped carbon (NC) composite polyhedrons linked with multi-walled carbon nanotubes (MWCNTs), CoS2@NC/MWCNT, were developed as an effective sulfur host for LSBs. It was fabricated through first in-situ growth of nanoporous ZIF-67 on surface treated MWCNTs, followed by carbonization and sulfurization. CoS2@NC/MWCNT combines the advantages of outstanding conductivities of MWCNTs, excellent chemical adsorption of NC and CoS2 toward LiPS, and high catalytic efficiency of CoS2 toward LiPS conversion, effectively addressing the shuttling, sluggish conversion, and low conductivity issues. The CoS2@NC/MWCNT electrode delivered a high specific capacity of 1133 mAh g-1 at 0.1 C and maintained a decent specific capacity of 607 mAh g-1 at 2.0 C. Its cycling stability is excellent, with a capacity retention rate of 77% after 300 cycles at 1.0 C, i.e., an average capacity decay rate of 0.078% per cycle. The cycling stability was further improved through increasing N-doping levels of the carbons for enhanced chemical adsorption toward LiPS and through incorporation of inter-linked reduced graphene oxide sheets as a physical barrier to reduce the diffusion loss of LiPS, achieving even smaller capacity decay rates of 0.066 and 0.064 % per cycle, respectively.

In this study, the graphene was successfully prepared via the reduction of graphene oxide (GO) used thiourea dioxide as a new reductant. The graphene oxide after reduction with thiourea dioxide has been characterized by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Raman photoelectron spectroscopy and transmission electron microscopy (TEM). The factors affecting reduction degree of graphene were discussed in the process of reduction, such as reduction time, temperature and the amount of reducing agent. The result shows that reduction degree of graphene is mainly controlled by temperature and reaction time. Finally, it is founded that the stronger reduction capacity of thiourea dioxide was attributed to the synergistic effect of its hydrolysis products, such as HSO3− and catalyze the ring-opening reaction.

Magnetic core–shell MnFe2O4@C and MnFe2O4@C-NH2 nanoparticles were successfully prepared by hydrothermal synthesis and well characterized by a variety of characterization methods. The carbon layers with a uniform thickness of about 2 nm could be clearly seen on the MnFe2O4 surface. The catalytic activity of these heterogeneous catalysts was estimated by the degradation of antibiotics. Ofloxacin (OFX), amoxicillin (AMX) and tetracycline (TC) were used as representative antibiotics. It was found that TC was the most refractory compound among the studied antibiotics. Compared to MnFe2O4, MnFe2O4@C and MnFe2O4@C-NH2 presented higher catalytic activity in the antibiotics and TOC removal. The enhanced catalytic activity of MnFe2O4@C-NH2 was ascribed to the carbon shell and the introduction of –NH2. The carbon shell enlarged the specific surface area, reduced the aggregation of magnetic nanoparticles and prevented the leaching of metal. The introduction of –NH2 enhanced the electron density of carbon shell and more electrons are transferred from carbon to the metal oxide, and thus more Mn2+ and Fe2+ species are produced. Based on the results of XPS and ESR spectra, a plausible mechanism for the generation of active species was proposed. MnFe2O4@C-NH2 was evaluated in the treatment of the mixed antibiotics solution. The results showed that the COD removal efficiency after 180 min of reaction was 63.8% and the corresponding BOD5/COD increased from 0.012 to 0.36. Finally, MnFe2O4@C-NH2 showed a high stability in the heterogeneous Fenton oxidation of the mixed antibiotics solution.

An adaptive dynamic covalent network with UV blocking and fluorescence is prepared by crosslinking hyperbranched polyglycerol (HPG) with itaconic anhydride (IA) via esterification. The abundant hydroxyl groups and ester linkages in the resulting polymer (HPG/IA) afford the dynamic transesterification at elevated temperatures and enable adaptive behaviors such as stress relaxation and reparability. Because the double bonds of IA are purposely reserved in the crosslinked network, the HPG/IA exhibits excellent UV blocking due to the strong UV absorption of the double bonds. HPG/IA also exhibits strong glass adherence. With a OH/anhydride ratio of 4/1, HPG/IA displays an adhesion shear strength to glass of ~30 kPa, which is explained by the flexible structure that ensures a good contact of the polymer film with glass and the high dielectric constant that favors accumulation of electrostatic charges. Interestingly, HPG/IA exhibits strong fluorescence (FL) under UV light, and the FL of HPG/IA exhibits strong selective quenching with respect to Fe3+. These unique properties make HPG/IA a promising functional material for UV blocking glass film and fluorescent Fe3+ sensor.

Phenol-laden saline wastewaters can adversely affect water, groundwater, soil, organisms and ecosystems. Given that frequently-used biodegradation process is generally inhibited by salinity, this work aims to solve the problem through a novel configuration of external extractive membrane bioreactor (EMBR) for the objective of simultaneous phenol permeation, salt rejection and biodegradation. Contact angles of 160.9 ± 2.2° (water) and 0.0° (phenol) were observed on the electrospun polydimethylsiloxane/polymethyl methacrylate (PDMS/PMMA) membrane, suggesting this superhydrophobic/superorganophilic membrane was suitable for separating phenol from water-soluble salt. Phenol ranging from 14.1 ± 2.7 to 290.7 ± 10.4 mg/L (stages 1 to 8) was continuously permeated and completely biodegraded in external EMBR under a hydraulic retention time (HRT) of 24 h, which corresponded with detoxification performance improving from 6.3% to 70.5%. After phenol exposure of 8 stages, Proteobacteria and Saccharibacteria became the main phyla for microorganisms. Enumeration of functional genes (phe, amoA, narG, nirS) confirmed that phenol was mainly consumed by denitrifiers and other heterotrophs as the sole carbon and energy source via oxidation and ring cleavage. As bacterial responses, these genes’ proliferation was promoted under low phenol concentrations but inhibited under high phenol concentrations. Meanwhile, results of extracellular polymeric substances revealed that protein was the key substance in toxicity resistance, phenol adsorption and transfer.