High Efficiency Blue Phosphorescent Organic Lighting-emitting Diodes with Novel Anode Structure

High-efficiency blue electrophosphorescent organic light-emitting devices employing MoO3 used as hole injection layer （HIL） and MoO3 doped N,N-dicarbazoly-3,5-benzene （mCP） as hole transport layer （HTL） were demonstrated. The blue OLED with the novel anode structure and TAPC used as electron blocking layer show a low turn-on voltage of 2.4 V, a maximum power efficiency of 33.6 lm/W at 3.1 V and 25 lrn/W with 1 000 cd/m2 at 3.8 V. It is also found that the efficiency of the devices is dependent on the different EBL materials. This is may because of relationship with the charge mobility and the triplet energy level of EBL materials. The device efficiency is determined by the charge balance which plays an important role.

Achieving blue water-dispersed room-temperature phosphorescence of carbonized polymer dots through nano-compositing with mesoporous silica

Stabilizing triplet excited states is important for room temperature phosphorescence(RTP)materials to achieve multifunctional applications in humid environment.However,due to the lack of preparation strategies,the realization of RTP materials in water still faces challenges.Herein,a new design strategy was presented to achieve RTP in water by confining carbonized polymer dots(CPDs)in amino functional mesoporous silica(MSNs-NH_(2)).The as-prepared MSNs-CPDs aqueous dispersion exhibited blue afterglow,lasting more than 3 s to naked eyes.The triplet excited states were protected from non-radiative deactivation by the double-confinement effect including covalent bonding fixation and mesoporous structure confinement.The MSNs-CPDs inherited the structure of MSNs-NH_(2),so the stability of morphology and properties were superior to CPDs and even most of silica-based CPDs RTP materials.A water-related encryption technique demonstrated the promising application of MSNs-CPDs as smart materials in the field of information security.Besides,the possibility of potential application in ion detection was also explored.

DNA detection based on Mn-doped ZnS quantum dots/methylene blue nanohybrids

Nanohybrids were formed from 3-mercaptopropionic acid （MPA）-coated Mn-doped ZnS quantum dots （QDs） and methylene blue （MB） via electrostatic interaction, and then used in the detection of trace DNA. The principle of detection is as follows： MB binds with Mn-doped ZnS QDs via electrostatic interaction, and then quenches the room temperature phosphorescence （RTP） of the QDs through photoinduced electron-transfer （PIET）. After the addition of DNA, MB binds with DNA through intercalation and electrostatic interaction, and desorbs from the surfaces of Mn-doped ZnS QDs, which recovers the RTP of the QDs. On this basis, a DNA detection method based on the properties of RTP was set up. This method shows a detection range of 0.2-20 mg/L, and a detection limit of 0.113 mg/L. Since this method is based on the RTP of QDs, it is not interfered by the background fluorescence or scattering light in vivo, and thus, avoids complex sample pretreatment. Thus, this method is very feasible for detection of trace DNA in biofluids.