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In this study, we investigate the influence of molecular geometry of the donor polymers and the perylene diimide dimers (di‐PDIs) on the bulk heterojunction (BHJ) morphology in the nonfullerene polymer solar cells (PSCs). The results reveal that the pseudo 2D conjugated poly[4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b;4,5‐b′]dithiophene‐2,6‐diyl‐alt‐(4‐(2‐ethylhexyl)‐3‐fluorothieno[3,4‐b]thiophene‐)‐2‐carboxylate‐2‐6‐diyl)] (PTB7‐Th) has better miscibility with both bay‐linked di‐PDI (B‐di‐PDI) and hydrazine‐linked di‐PDI (H‐di‐PDI) compared to its 1D analog, poly[[4,8‐bis[(2‐ethylhexyl)oxy]benzo[1,2‐b:4,5‐b′]dithiophene‐2,6‐diyl][3‐fluoro‐2‐[(2‐ethylhexyl)carbonyl]thieno[3,4‐b]thiophenediyl]] (PTB7), to facilitate more efficient exciton dissociation in the BHJ films. However, the face‐on oriented π–π stacking of PTB7‐Th is severely disrupted by the B‐di‐PDI due to its more flexible structure. On the contrary, the face‐on oriented π–π stacking is only slightly disrupted by the H‐di‐PDI, which has a more rigid structure to provide suitable percolation pathways for charge transport. As a result, a very high power conversion efficiency (PCE) of 6.41% is achieved in the PTB7‐Th:H‐di‐PDI derived device. This study shows that it is critical to pair suitable polymer donor and di‐PDI‐based acceptor to obtain proper BHJ morphology for achieving high PCE in the nonfullerene PSCs.

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Reduction of Cr(VI) is often deemed necessary to detoxify chromium contaminants; however, few investigations utilized this reaction for the purpose of treating other industrial wastewaters. Here a widely used Cr(VI)-sulfite reaction system was upgraded to simultaneously transform multiple pollutants, namely, the reduction of Cr(VI) and oxidation of sulfite and other organic/inorganic pollutants in an acidic solution. As(III) was selected as a probe pollutant to examine the oxidation capacity of a Cr(VI)-sulfite system. Both (•)OH and SO4(•-) were considered as the primary oxidants for As(III) oxidation, based on the results of electron spin resonance, fluorescence spectroscopy, and specific radicals quenching. As(III)-scavenging, oxidative radicals greatly accelerated Cr(VI) reduction and simultaneously consumed less sulfite. In comparison with a Cr(VI)-H2O2 system with 50 μM Cr(VI), Cr(VI), the sulfite system had excellent performance for both As(III) oxidation and Cr(VI) reduction at pH 3.5. Moreover, in this escalated process, less sulfite was required to reduce Cr(VI) than the traditional Cr(VI) reduction by sulfite process. This effectively improves the environmental compatibility of this Cr(VI) detoxification process, alleviating the potential for SO2 release and sulfate ion production in water. Generally, this study provides an excellent example of a "waste control by waste" strategy for the detoxification of multiple industrial pollutants.

Arsenic and chromium are often abundant constituents of acid mine drainage (AMD) and are most harmful as arsenite (As(III)) and hexavalent (Cr(VI)). To simultaneously change their oxidation state from As(III) to As(V), and Cr(VI) to Cr(III), is a potentially effective and attractive strategy for environmental remediation. The coabundance of As(III) and Cr(VI) in natural environments indicates their negligible direct interaction. The addition of H2O2 enables and greatly accelerates the simultaneous oxidation of As(III) and reduction of Cr(VI). These reactions are further enhanced at acidic pH and higher concentrations of Cr(VI). However, the presence of ligands (i.e., oxalate, citrate, pyrophosphate) greatly retards the oxidation of As(III), even though it enhances the reduction of Cr(VI). To explain these results we propose a reaction mechanism where Cr(VI) is primarily reduced to Cr(III) by H2O2, via the intermediate tetraperoxochromate Cr(V). Cr(V) is then involved in the formation of (•)OH radicals. In the presence of ligands, the capacity of Cr(V) to form (•)OH radicals, which are primarily responsible for As(III) oxidation, is practically inhibited. Our findings demonstrate the feasibility for the coconversion of As(III) and Cr(VI) in AMD and real-world constraints to this strategy for environmental remediation.

An efficient and green advanced oxidation process (i.e., photo-sulfite reaction) for the simultaneous oxidation of sulfite and organic pollutants in water is reported. The photo-sulfite system (UV-Fe(III)-sulfite) is based on the Fe-catalyzed sulfite oxidation and photochemistry of Fe(III) species. SO4(•-) and (•)OH radicals were identified in the photo-sulfite system with radical scavenging experiments using specific alcohols. This novel technology was consistently proven to be more favorable than the alternative Fe(III)-sulfite systems for the degradation of 2,4,6-trichlorophenol (2,4,6-TCP) and other organic pollutants at all conditions tested. The reactivity of photo-sulfite system was sustained due to the spontaneous switch of photoactive species from Fe(III)-sulfito to Fe(III)-hydroxo complexes with the depletion of sulfite and the decrease in pH. In contrast, in the absence of light the performance of the Fe(III)-sulfite system was greatly diminished after the consumption of sulfite. The formation of the Fe(III)-sulfito complex is a necessary step for initiating the photo-sulfite reaction. Inhibition of the oxidation of 2,4,6-TCP and methyl orange (MO) was observed in the presence of ligands that can stabilize one or more of the reactants: Fe(III), Fe(II), or sulfite. Our study provides a new facile route for the generation of SO4(•-) and simultaneous removal of organic and inorganic pollutants.

The aim of the present study was to prepare and evaluate a paclitaxel nanocrystal-based formulation stabilized by serum protein transferrin in a non-covalent manner. The pure paclitaxel nanocrystals were first prepared using an antisolvent precipitation method augmented by sonication. The serum protein transferrin was selected for use after evaluating the stabilizing effect of several serum proteins including albumin and immunoglobulin G. The formulation contained approximately 55~60% drug and was stable for at least 3 months at 4 °C. In vivo antitumor efficacy studies using mice inoculated with KB cells demonstrate significantly higher tumor inhibition rate of 45.1% for paclitaxel-transferrin formulation compared to 28.8% for paclitaxel nanosuspension treatment alone. Interestingly, the Taxol® formulation showed higher antitumor activity than the paclitaxel-transferrin formulation, achieving a 93.3% tumor inhibition rate 12 days post initial dosing. However, the paclitaxel-transferrin formulation showed a lower level of toxicity, which is indicated by steady increase in body weight of mice over the treatment period. In comparison, treatment with Taxol® resulted in toxicity issues as body weight decreased. These results suggest the potential benefit of using a serum protein in a non-covalent manner in conjunction with paclitaxel nanocrystals as a promising drug delivery model for anticancer therapy.