Perovskite-fullerene hybrid materials suppress hysteresis in planar diodes.

Solution-processed planar perovskite devices are highly desirable in a wide variety of optoelectronic applications; however, they are prone to hysteresis and current instabilities. Here we report the first perovskite-PCBM hybrid solid with significantly reduced hysteresis and recombination loss achieved in a single step. This new material displays an efficient electrically coupled microstructure: PCBM is homogeneously distributed throughout the film at perovskite grain boundaries.

Perovskite thin films via atomic layer deposition.

A new method to deposit perovskite thin films that benefit from the thickness control and conformality of atomic layer deposition (ALD) is detailed. A seed layer of ALD PbS is place-exchanged with PbI2 and subsequently CH3 NH3 PbI3 perovskite. These films show promising optical properties, with gain coefficients of 3200 ± 830 cm(-1) .

Synthesis and application of photolithographically patternable deep blue emitting poly(3,6-dimethoxy-9,9-dialkylsilafluorene)s.

Poly(silafluorene)s (PSFs) are promising light-emitting materials with brilliant solid-state blue luminescence, high quantum efficiency, excellent solubility, and improved thermal and chemical stability. PSFs are reported to have high electron affinity and conductivity originating from σ*-π* conjugation between the σ*-antibonding orbital of the exocyclic Si-C bond and the π* antibonding orbital of the butadiene fragment, a promising characteristic for improved charge carrier balance in OLEDs. In this paper, we present a protocol for photopatterning derivatives of poly(3,6-dimethoxy-9,9-dialkylsilafluorenes) with resolutions exceeding 10 μm.

Electroactuation of alkoxysilane-functionalized polyferrocenylsilane microfibers.

Cross-linked conductive polymer networks that mediate chemical, electronic, optical, and mechanical signals are enticing materials from which to construct actuators and sensors as well as more complex polymer-fiber-based structures capable of emulating natural cytoskeletal stress fibers such as actin. In this work we have synthesized and characterized a novel class of high molecular weight electroactive polyferrocenylsilane (PFS) that has been functionalized with pendant alkoxysilane groups and which can be conveniently gelled by sulfonic acid catalyzed condensation of the cross-linkable alkoxysilanes. These PFS electroactive gels are capable of converting an electrical signal to mechanical stress and strain as a result of a change in dimension in response to electrochemical oxidation or reduction coupled with transport of charge balancing ions and solvent molecules in PFS.