Haiqing Yao

Bio: Haiqing Yao is an academic researcher from Texas A&M University. The author has contributed to research in topics: Graphene & Epoxy. The author has an hindex of 13, co-authored 20 publications receiving 563 citations. Previous affiliations of Haiqing Yao include Wuhan University & Nankai University.

Tunable Lyotropic Photonic Liquid Crystal Based on Graphene Oxide

Abstract: A direct colloidal self-assembly approach was utilized to prepare photonic crystals based on exfoliated graphene oxide (GO) in aqueous solution. The GO sheets form ordered photonic structure spontaneously without the need for multiple processing steps. The wavelength of light reflected by the GO photonic crystal dispersion can be controlled over the entire visible light spectrum simply by varying the GO concentration. The aspect ratio of the GO sheets and mediation of the intersheet forces are found to be the key factors influencing the stability of photonic crystal formation. The usefulness and limitations of the GO photonic crystals prepared in this study are discussed.

Organic host materials for phosphorescent organic light-emitting diodes

Abstract: Phosphorescent organic light-emitting diodes (PhOLEDs) unfurl a bright future for the next generation of flat-panel displays and lighting sources due to their merit of high quantum efficiency compared with fluorescent OLEDs. This critical review focuses on small-molecular organic host materials as triplet guest emitters in PhOLEDs. At first, some typical hole and electron transport materials used in OLEDs are briefly introduced. Then the hole transport-type, electron transport-type, bipolar transport host materials and the pure-hydrocarbon compounds are comprehensively presented. The molecular design concept, molecular structures and physical properties such as triplet energy, HOMO/LUMO energy levels, thermal and morphological stabilities, and the applications of host materials in PhOLEDs are reviewed (152 references).

Novel organic electroluminescent compounds and organic electroluminescent device using the same

Abstract: The present invention relates to novel organic electroluminescent compounds exhibiting high luminous efficiency, and organic electroluminescent devices comprising the same. The organic electroluminescent compounds according to the invention are represented by Chemical Formula (1):

Blue fluorescent emitters: design tactics and applications in organic light-emitting diodes

Abstract: Organic light-emitting diodes (OLEDs) are competitive candidates for the next generation flat-panel displays and solid state lighting sources. Efficient blue-emitting materials have been one of the most important prerequisites to kick off the commercialization of OLEDs. This tutorial review focuses on the design of blue fluorescent emitters and their applications in OLEDs. At first, some typical blue fluorescent materials as dopants are briefly introduced. Then nondoped blue emitters of hydrocarbon compounds are presented. Finally, the nondoped blue emitters endowed with hole-, electron- and bipolar-transporting abilities are comprehensively reviewed. The key issues on suppressing close-packing, achieving pure blue chromaticity, improving thermal and morphological stabilities, manipulating charge transporting abilities, simplifying device structures and the applications in panchromatic OLEDs are discussed.

Harnessing the chemistry of graphene oxide

Abstract: Our understanding of the fundamental structure and bonding of graphene oxide (GO) as well as the scope of its utility have grown tremendously over the past decade. As a result, the pace of research efforts directed toward this carbon material continues to increase. Contemporary application now intersects a variety of disciplines and includes heterogeneous catalysis, flow reactor technologies, biomedicine and biotechnology, polymer composites, energy storage, and chemical sensors. Advances in these areas have been buoyed by improvements in the methods used to synthesize and characterize GO, as well as functionalized derivatives thereof. While the diverse uses of GO have been reviewed previously, herein we provide an overview of some of the most recent and significant developments in the field. A brief overview of GO's synthesis and characterization is also provided as well as several recently proposed structural models. The inherent reactivity of GO is described in the context of catalysis, and the utilization of GO's reactive oxygen groups and carbon framework to prepare functionalized derivatives is also discussed. Finally, we provide an outlook of potential areas where GO, its derivatives, and related materials may be expected to find utility or opportunity for further growth and study.

Materials for organic electroluminescent devices

Abstract: The present invention relates to compounds of the formula (1) which are suitable for use in electronic devices, in particular organic electroluminescent devices, and to electronic devices which contain these compounds.