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The diffusion of stubborn oils and organic pigments has become a severe environmental pollution problem. Promisingly, the combination of superhydrophobicity and photocatalysis is expected to provide an efficient, economical and simple solution. In this paper, a kind of superhydrophobic and super-lipophilicity polyurethane (PU)-based sponge was reported by a strategy of undergoing ferric tetroxide loading (Fe3O4@PU), polydopamine fixation (PDA-Fe3O4@PU), octadecylamine grafting (ODA-Fe3O4@PU) and molybdenum disulfide loading (MoS2-ODA-Fe3O4@PU) successively. The results show that the MoS2-ODA-Fe3O4@PU sponge exhibits outstanding superhydrophobicity (with maximum water contact angle of 161.64°), excellent oil absorption capacity (60–109 wt/wt), robust stability in extreme environments and great oil/water separation ability. In addition, the MoS2-loaded sponge demonstrates desirable outcomes in decomposing methyl orange and methylene blue under light source, and a dual-functional purification system with a heterogeneous polyurethane-based sponge (the upper part is MoS2-ODA-Fe3O4@PU and the bottom part is MoS2@PU) endowed with superhydrophobicity and photocatalysis can purify water by separating oils and decomposing methylene blue simultaneously.

Organophosphorus flame retardants (OPFRs) have been detected ubiquitously in the air and water worldwide, but no study has focused on their air-water exchange process. Here, we investigated the concentrations, distributions, and seasonal variations of OPFRs in the coastal air and water of Dalian, China. The total concentrations of 10 OPFRs in the air based on passive air sampling ranged from 0.50 to 20.0 ng/m3, while the concentrations of OPFRs in the water dissolved phase ranged from 48.3 to 681 ng/L. Relatively high concentrations were mainly discovered near the industry areas or river estuaries, suggesting that point sources along the coastline may significantly influence the local OPFR concentrations. Tris(2-chloroisopropyl) phosphate (TCIPP) was the most dominant congener followed by tris(2-chloroethyl) phosphate (TCEP), which was consistent with their high production and persistence. The air-water gaseous exchanges of OPFRs were estimated for the first time according to their concentrations in gaseous and dissolved phases. Generally, the gaseous exchange fluxes varied with sampling site and period. TCIPP showed the highest gaseous deposition flux of −395 ± 1211 ng/(m2 d), while TCEP showed the highest emission flux of 1414 ± 2093 ng/(m2 d). The dry deposition fluxes of OPFRs (0.05–822 ng/(m2 d)) were also calculated based on their particle fractions in the air. The result suggested that both gaseous exchange and particle deposition processes significantly influenced the air-water transport of OPFRs in this area.

In this study, polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), and dechlorane plus (DPs) were analyzed in seven categories of building and decoration materials. The total concentrations of analyzed FRs ranged from 1.19 ng/g (diatomite powder) to 9532 ng/g (expanded polystyrene panel). Relatively high concentrations were detected in foam samples and PVC materials, followed by sealing materials, boards, wallpaper, paints, and wall decoration powders. BDE209 was the most detected compound with the highest concentrations in almost all materials, followed by decabromodiphenyl ethane (DBDPE), which was consistent with their productions and consumptions in China. The estimated PBDE concentrations in air and dust based on material concentration and emission rate were comparable with those detected in real samples. Adult and infant exposures via inhalation and dust ingestion were assessed. The estimated exposures to BDE209 via dust ingestion were 1.36 and 0.12 ng/(kg bw d), which were 19- and 4-fold higher than those via inhalation for infants and adults, respectively. This suggested that dust ingestion was a significant pathway of human BDE209 exposure, especially for infants. For the other PBDE congeners (∑7PBDEs), the estimated exposures via inhalation were 2.60 and 1.32 ng/(kg bw d) for infants and adults, respectively. Despite the low estimated human exposures to PBDEs compared to the oral reference doses, the exposure associated with building and decoration materials still requires more attention because of the potential risks from other exposure pathways and undetected FRs in those materials.

Three-dimensional porous sponge has been demonstrated as an outstanding candidate in oil/water separation due to its hydrophobicity and oleophilicity that originates from the synergistic effect of rough structure and low surface energy, but the separation process has not been illuminated clearly. This paper presents the study of the synthesis of oil/water separation sponge, mechanism of separation process and establishment of kinetic model, via the combination among dopamine chemistry, covalent modification, theoretical analysis, experimental results and mathematical model. Results show that both the dopamine deposition time and the octadecyltrimethoxysilane hydrolysis system significantly affect the hydrophobicity of the modified-melamine sponge and that the oil/water separation process is composed of six scenarios with different physical state. Furthermore, with the experimental results, established iso-potential separation model and the height-quantized model, we conclude that the time-dependent separation patterns and kinetics are subjected to the modulation of the viscosity of the separated substance and the immersion depth of the sponge.

Studying the reaction mechanism of materials in the process of lithiation/delithiation is important to understand and optimize the electrode materials. In this work, the petal-like CoSe is prepared by a simple hydrothermal method, and its lithium storage mechanism is studied. During the charge/discharge cycles, the capacity of the CoSe decreases first and then increases. In the initial stage, the volume of CoSe expands due to the intercalation of lithium ions, which results in the amorphousness of CoSe and reduces the specific capacity. The subsequent increase in capacity is due to the recrystallization of the material and the formation of a conductive SEI film. The petal-like CoSe displays a specific capacity of 450 mA h g−1 at the current density of 100 mA g−1 after 300 cycles. To improve the lithium storage performance, a CoSe/rGO composite is prepared. The addition of GO during the preparation of CoSe changes the morphology of CoSe from a larger petal shape to a smaller rod shape, which weakens the effect of volume change during lithium ion intercalation and shortens the lithium ion diffusion distance, so improves the reduction of specific capacity. At a current density of 100 mA g−1, the specific capacity of CoSe/rGO composite can be as high as 730 mA h g−1 after 200 cycles. Even under a large current density of 1000 mA g−1, the specific capacity of the CoSe/rGO composite can still reach 570 mA h g−1 after 1000 cycles.

A microscale soot-particulate sensor using interdigitated platinum-gallium nitride (Pt-GaN) Schottky interfaces was developed to monitor fine soot particles within high-temperature environments (e.g., combustion exhausts and flues). Upon exposure to soot particles (30 to 50 nm in diameter) from an experimental chimney, an increased current (∼43.6%) is observed through the back-to-back Schottky contact to n-type GaN. This is attributed to a reduction in the effective Schottky barrier height (SBH) of ∼10 meV due to the electric field from the charged soot particles in the depletion region and exposed GaN surface. Furthermore, the microfabricated sensor was shown to recover sensitivity and regenerate the sensing response (∼11 meV SBH reduction) after exposure to temperature as high as 550 °C. This study supports the feasibility of a simple and reliable soot sensor to meet the increasing market demand for particulate matter sensing in harsh environments.