Disclosed are a QLED display panel and a preparation method thereof and a display apparatus. The QLED display panel includes: a first and second substrates oppositely disposed; a first electrode, a hole injection layer, a hole transport layer, a quantum dot luminescent layer, an electron transport layer and a second electrode formed between the first and second substrates and disposed sequentially along a direction from the first substrate to the second substrate; and a first ionic coordination compound layer formed on a side facing quantum dot luminescent layer, of hole transport layer. The first ionic coordination compound layer includes a first positive and a first negative ion portions; the first positive ion portion is on a side close to hole transport layer, of first ionic coordination compound layer, and the first negative ion portion is on a side close to quantum dot luminescent layer, of first ionic coordination compound layer.

The dye-sensitized solar cell comprises a first electrode including a porous semiconductor layer supporting a dye; and a second electrode serving as a counter electrode of the first electrode. The second electrode includes a counter electrode conductive layer containing an absorbent supporting a dye that is the same as or different from the dye supported by the porous semiconductor layer.

Light emitting electrochemical cell devices comprising chiral liquid crystalline materials. The chiral liquid crystalline material mixtures of the devices function as both electrolytes and as light emitting materials. The chiral liquid crystalline material mixtures also form photonic crystal structures creating a photonic stop band. The presence of the photonic stop band enables the light emitting electrochemical cell devices to emit light with improved energy efficiency.

An organic electroluminescence device according to an embodiment of the present disclosure includes a first electrode, a second electrode, and an emission layer. The emission layer includes host compounds and dopant compounds. The hot compounds include a first host compound represented by Formula 1, and a second host compound represented by Formula 2, and the dopant compounds include an assistant dopant compound represented by Formula 3, and a light-emitting dopant compound represented by Formula 4:

##STR00001##

Accordingly, the organic electroluminescence device according to an embodiment may achieve high efficiency and long life.

This invention discloses a novel multicomponent system or a single compound that is capable of performing triplet-triplet annihilation up conversion process. (TTA-UC) A solution or solid film that comprises this TTA-UC system or compound is provided. This system or compound can be used in an optical or optoelectronic device.

Forward and back electron transfer at molecule oxide interfaces are pivotal events in dye-sensitized solar cells, dye-sensitized photoelectrosynthesis cells and other applications. Disclosed herein are self-assembled multilayers as a strategy for manipulating electron transfer dynamics at these interfaces. The multilayer films are achieved by stepwise layering of bridging molecules, linking ions, and active molecule on an oxide surface. The formation of the proposed architecture is supported by ATR-IR and UV-Vis spectroscopy. Time-resolved emission and transient absorption establishes that the films exhibit an exponential decrease in electron transfer rate with increasing bridge length. The findings indicate that self-assembled multilayers offer a simple, straight forward and modular method for manipulating electron transfer dynamics at dye-oxide interfaces.

A compound comprising a first ligand L.sub.A having the formula

##STR00001##

Formula I, is disclosed. In Formula I, ring A is a five- or six-membered carbocyclic or heterocyclic ring; Y.sup.1 is selected from carbon and nitrogen; each of X.sup.1 to X.sup.4 is C or N; at least two adjacent R.sup.2s of ring B form a fused structure having the following formula:

##STR00002##

ring C is fused to ring B and the wavy lines are bonds attached to ring B; ring D and ring E are either a 5-membered aromatic ring or a 6-membered aromatic ring; each R.sup.1, R.sup.2, R.sup.3, R.sup.A, R.sup.B, R.sup.C, and R.sup.D is independently selected from a variety of substituents; ligand L.sub.A is coordinated to a metal M and, optionally, linked with other ligands; and M is optionally coordinated to other ligands. Organic light emitting devices and consumer products containing the compounds are also disclosed.

There are provided a photoelectric conversion element and a photoelectric conversion element module including the photoelectric conversion element, the photoelectric conversion element including a transparent substrate, a first and second transparent conductive layer arranged on the transparent substrate, a photoelectric conversion layer arranged on the first transparent conductive layer, a porous insulating layer covering the photoelectric conversion layer, a reflective layer arranged on the porous insulating layer, and a counter conductive layer that are arranged on the reflective layer, in which the photoelectric conversion layer contains a porous semiconductor, a carrier-transport material, and a photosensitizer, and in which an area of the orthogonal projection of the porous insulating layer onto the transparent substrate and an area of the orthogonal projection of the reflective layer onto the transparent substrate are each larger than an area of the orthogonal projection of the photoelectric conversion layer onto the transparent substrate.

The present invention includes novel hexadentate metal complexes. The complexes hexadentate ligands of the present invention may be useful as improved emitters in an OLED device.

A light emitting device contains an anode, cathode, and two organic layers provided therebetween. One organic layer contains a phosphorescent compound, the second organic layer contains a block copolymer containing an end group, a block that binds to the end group and/or a block that does not bind to the end group, and a crosslinked product of the block copolymer. The non-terminal block contains a non-crosslinkable unit represented by the formula (X) and/or a non-crosslinkable unit represented by the formula (Z). At least one of X.sub.I>X.sub.II; Z.sub.I>Z.sub.II; X.sub.I+Z.sub.I>X.sub.II+Z.sub.II is satisfied when the total number of units having formula (X) and the total number of units having formula (Z) in the non-terminal block are X.sub.I and Z.sub.I, respectively, and the total number of units having formula (X) and the total number of units having formula (Z) in the terminal block are X.sub.II and Z.sub.II, respectively.