Giant Molecule Acceptor Enables Highly Efficient Organic Solar Cells Processed Using Non-halogenated Solvent.

High efficiency organic solar cells (OSCs) based on A-DA'D-A type small molecule acceptors (SMAs) were mostly fabricated by toxic halogenated solvent processing, and power conversion efficiency (PCE) of the non-halogenated solvent processed OSCs is mainly restricted by the excessive aggregation of the SMAs. To address this issue, we developed two vinyl π-spacer linking-site isomerized giant molecule acceptors (GMAs) with the π-spacer linking on the inner carbon (EV-i) or out carbon (EV-o) of benzene end group of the SMA with longer alkyl side chains (ECOD) for the capability of non-halogenated solvent-processing. Interestingly, EV-i possesses a twisted molecular structure but enhanced conjugation, while EV-o shows a better planar molecular structure but weakened conjugation. The OSC with EV-i as acceptor processed by the non-halogenated solvent o-xylene (o-XY) demonstrated a higher PCE of 18.27 % than that of the devices based on the acceptor of ECOD (16.40 %) or EV-o (2.50 %). 18.27 % is one of the highest PCEs among the OSCs fabricated from non-halogenated solvents so far, benefitted from the suitable twisted structure, stronger absorbance and high charge carrier mobility of EV-i. The results indicate that the GMAs with suitable linking site would be the excellent candidates for fabricating high performance OSCs processed by non-halogenated solvents.

Biodegradation of polybutylene adipate-co-terephthalate by Priestia megaterium, Pseudomonas mendocina, and Pseudomonas pseudoalcaligenes following incubation in the soil.

Soil that contained polybutylene adipate-co-terephthalate (PBAT) was incubated with Priestia megaterium, Pseudomonas mendocina, and Pseudomonas pseudoalcaligenes to improve the biodegradative process of this polymer. The mixture of Pr. megaterium and Ps. mendocina was highly effective at biodegrading the PBAT, and after eight weeks of soil incubation, approximately 84% of the PBAT film weight was lost. Mixtures of the other two species also positively affected the synergistic degradation of PBAT film in the soil, but the mixture of three species had a negative effect. The residual PBAT film microstructure clearly demonstrated the degradation of PBAT, and the degree of degradation was related to the different species. Cleavage of the PBAT film ester bond after soil microbial action affected its properties. The incubation of PBAT in soil that contained these species affected soil dehydrogenase and soil lipase in particular. The secretion of lipase by these species could play an important role in the degradation of PBAT in the soil.

Structural versatility and luminescent properties in d(10) metal ion polymers with 1,4-naphthalenedicarboxylate acid and 4,4'-dipyridyl N,N'-dioxide.

Hydrothermal reactions of d(10) metal ions (Cd(2+) and Zn(2+)) with 1,4-naphthalenedicarboxylate acid (1,4-H2NDC) and 4,4'-dipyridyl N,N'-dioxide (4,4'-dpdo) form two three-dimensional grid-like coordination polymers [Cd2(1,4-NDC)2(4,4'-dpdo)]·H2O 1 and [Zn4(µ3-OH)2(1,4-NDC)3(H2O)2](4,4'-dpdo)·2H2O 2. Both coordination polymers were characterized by single crystal X-ray diffraction, IR spectroscopy, XRPD, thermogravimetric and elemental analyses. Polymer 1 exhibits rare alternating arranged 1,4-NDC(2)(-) and 4,4'-dpdo spacers between adjacent 1D zigzag chains containing Cd-octahedral coordination geometries. Polymer 2 is constructed from infrequent chair-like [Zn4(µ3-OH)2](6+) inorganic SBUs with four- and six-coordination geometries and only 1,4-NDC(2)(-) as "single-bridge" and "double-bridges" to form a 3D framework. Both polymers give strong luminescent emissions in the solid state at room temperature.