ABSTRACT
The realization of high-performance optoelectronic devices requires excellent charge-transporting layers and efficient carrier recombination. Herein, we synthesized cesium tungsten bronze (Cs0.32WO3) nanocrystals and utilized them as the hole-transporting material to fabricate all-inorganic perovskite light-emitting diodes (PeLEDs). Due to the excellent carrier balance characteristics via comparison between the hole-only device and electron-only device, the all-inorganic PeLEDs with CsPbBr3 as the light-emitting layer present the maximum current efficiency of 31.51 cd/A and external quantum efficiency (EQE) of 8.48%, which are self-evidently enhanced compared with the PEDOT:PSS (14.78 cd/A, 4.03%) and WO3 (24.75 cd/A, 6.18%) based devices. Considering the remarkably improved device performance, the proposed HTL of Cs0.32WO3 is promising, acting as a favorable building block for high-efficiency light-emitting devices.
ABSTRACT
In the Forestry Experimental Station of Shandong Agricultural University, we determined the photosynthetic physiological and biochemical indexes including photosynthetic parameters, chlorophyll fluorescence, and chlorophyll content of one-year-old poplar seedlings under different doses (0.17, 0.33, 0.67, 1.00, 1.33 and 1.67 g·kg-1) of Chaetomium globosmn ND35 fungus fertilizer treatment to study the effects of fungus fertilizer on photosynthesis of poplar in replanted soil. The results showed that with the increase of fungus fertilizer dose, the chlorophyll content of poplar lea-ves (Chl) showed an increasing trend, while the physiological indexes such as electron transport rate (ETR), net photosynthetic rate (Pn), quantum efficiency (Φ), nitrate reductase (NR) activity and root vigor showed an increasing first and then decreasing trend. Meanwhile, the heat dissipation that depended on xanthophyll cycle decreased and non-photochemical quenching (NPQ) increased first and then decreased. When the dose of C. globosmn ND35 fungus fertilizer was 0.67 g·kg-1 or 1.00 g·kg-1, excess light energy of photosynthetic apparatus was reduced, and photosynthetic apparatus distributed more light energy to the direction of photochemical reactions, which improved the energy use efficiency. Applying an appropriate amount (0.67-1.00 g·kg-1) of C. globosmn ND35 fungus fertilizer could improve root physiological activity and light use ability of poplar leaves, which was conducive to the improvement of operating states of photosynthetic apparatus, and then increased the photosynthetic efficiency of the poplar leaves.
