Growing interests have been devoted to the design of polymer acceptors as potential replacement for fullerene derivatives for high-performance all polymer solar cells (all-PSCs). One key factor that is limiting the efficiency of all-PSCs is the low fill factor (FF) (normally <0.65), which is strongly correlated with the mobility and film morphology of polymer:polymer blends. In this work, we find a facile method to modulate the crystallinity of the well-known naphthalene diimide (NDI) based polymer N2200, by replacing a certain amount of bithiophene (2T) units in the N2200 backbone by single thiophene (T) units and synthesizing a series of random polymers PNDI-Tx, where x is the percentage of the single T. The acceptor PNDI-T10 is properly miscible with the low band gap donor polymer PTB7-Th, and the nanostructured blend promotes efficient exciton dissociation and charge transport. Solvent annealing (SA) enables higher hole and electron mobilities, and further suppresses the bimolecular recombination. As expected, the PTB7-Th:PNDI-T10 solar cells attain a high PCE of 7.6%, which is a 2-fold increase compared to that of PTB7-Th:N2200 solar cells. The FF of 0.71 reaches the highest value among all-PSCs to date. Our work demonstrates a rational design for fine-tuned crystallinity of polymer acceptors, and reveals the high potential of all-PSCs through structure and morphology engineering of semicrystalline polymer:polymer blends.

Cesium‐based all‐inorganic perovskite solar cells (PSCs), especially for CsPbI2Br component‐based devices, have attracted increasing attention due to its advantage of superior thermal and phase stability. Since the pioneering study reported in 2016, more than 30 papers have been published, reporting the rapid boost in the power conversion efficiency (PCE) of PSCs to 14.81%. The CsPbI2Br PSC is one of the most remarkable research hotspots in the field of perovskite photovoltaics. In this progress report, the recent advances in CsPbI2Br PSCs are systematically reviewed, which in turn introduces the basic property and stability of active layers, and the performance improvements in these devices. The challenges as well as the possible solutions toward better‐performing CsPbI2Br PSCs are also discussed. The theoretical calculation results point out that there is much room for further device performance enhancement, particularly in open‐circuit voltages. This progress report focuses on CsPbI2Br material properties and summarizes recent strategies to improve the corresponding device's PCE, in order to open new perspectives toward commercial utility of PSCs.

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The aim of this study was to improve the water resistance of a soybean meal-based adhesive with a low-cost lignin-based resin (LR).

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An ideal gene carrier is required both in safety and efficiency for transfection. Polyethylenimine (PEI), a well-studied cationic polymer, has been proved with high transfection efficiency, but is reported as toxicity in many cell lines. In this study, PEI was coupled with polyethylene glycol (PEG) to reduce its cytotoxicity. PEG-PEI copolymers were synthesized with isoporon diisocyanate (IPDI) in two steps. A set of PEG-PEI with different PEG molecular weights (MWs) and amounts of PEG were synthesized. The molecular structure of the resulting copolymers was evaluated by nuclear magnetic resonance spectroscopy ((1)H NMR), infrared spectroscopy (IR), and gel permeation chromatography (GPC), all of which had successfully verified formation of the copolymers. The particle size and zeta potential of polymer/DNA complexes were measured, and their cytotoxicity and transfection efficiency in Hela cells were evaluated. We found that the copolymer block structure significantly influenced not only the physicochemical properties of complexes, but also their cytotoxicity and transfection efficiency. PEG (5 kDa) significantly reduced the diameter of the spherical complexes. The zeta potential of complexes was reduced with increasing amount of PEG grafting. Cytotoxicity was dependent not on PEG MW but on the amount of PEG grafting. Copolymer PEG-PEI (2-25-1) with 1.89 PEG (2 kDa) was proved to be more efficient for in vitro gene transfer. In conclusion, PEG MW and the degree of PEGylation were found to significantly influence the biological activity of PEG-PEI/DNA complexes. These results provide new sights into the studies using block copolymer as gene delivery systems.

Lactose reduced dairy products are more prone to Maillard reactions due to the presence of reactive monosaccharides. Conventional β-galactosidases, which are used for lactose hydrolysis in lactose-reduced dairy products, will lead to conversion of lactose into glucose and galactose, where especially galactose is very reactive during Maillard reactions. Some β-galactosidases have transgalactosylating activity and will thus convert lactose into galacto-oligosaccharides (GOS) and hereby limit the release of galactose. The aim of this study was to investigate the extent of participation of GOS in Maillard reactions in comparison to lactose, a 50:50 mixture of glucose and galactose, and galactose exclusively in sodium caseinate-based milk-like model systems heated at 130 and 75 °C at pH 6.8. The GOS system exhibited reduced loss of free amino groups; accumulated less furosine and less of the following advanced glycation end products (AGEs): Nε-carboxyethyl lysine, methylglyoxal-derived hydroimidazolone isomers, glyoxal-derived lysine dimer, and methylglyoxal-derived lysine dimer; and also developed less browning compared to monosaccharide models. However, the GOS–caseinate system accumulated more 3-deoxyglucosone and 3-deoxygalactosone, which resulted in higher concentrations of 5-(hydroxymethyl)­furfural and pyrraline. The results indicated that GOS overall participate less readily in Maillard reactions than the monosaccharides investigated but were more prone to degradation to C6 α-dicarbonyls species. Finally, relationship analysis indicated that C6 α-dicarbonyls seemed to primarily increase concentrations of 5-(hydroxymethyl)­furfural instead of AGEs. Our results suggest that conversion of lactose into GOS instead of monosaccharides in milk by transgalactosylating β-galactosidases could be a useful strategy for production of lactose-free milk for people with lactose intolerance.