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To evade the hurdles of dendrite growth and low Coulombic efficiency resulting from lithium metal anodes, integrating lithiated silicon anodes with sulfur cathodes to configure a lithiated silicon-sulfur (Si-S) full cell is a promising strategy to develop high-energy and high-safety rechargeable lithium batteries. Nevertheless, Si-S full cells always suffer accelerated capacity decay, even when excellent electrochemical performance of Li-S and Li-Si half cells is achieved. Herein, we report a comprehensive investigation of the capacity fade mechanism of Si-S full cells. It is revealed that cyclable lithium loss plays a key role in the accelerated capacity fade of Si-S full cells. In addition, cyclable lithium loss in Si-S full cells is mainly divided into irreversible lithium loss by forming inactive lithium compounds due to polysulfide shuttling and other side reactions, and restricted lithium because the Si/C anode cannot be fully delithiated when the Si-S full cell reaches the discharge cutoff voltage. From the 1st cycle to the 100th cycle, the irreversible lithium loss is determined to have increased from 21.7 to 54.5%, whereas the restricted lithium decreased from 24.6 to 16.7%, respectively. The high specific surface area of a Si/C anode leads to a remarkable irreversible lithium loss due to serious polysulfide shuttling in Si-S full cells. This work will help advance the practical application of Li-S batteries.

A solution-processed molybdenum oxide (MoOx) as the hole injection layer (HIL) by doctor-blade coating was developed to improve the efficiency and lifetime of red-emitting quantum-dot light-emitting diodes (QD-LEDs). It has been demonstrated that by adding isopropyl alcohol into the MoOx precursor during the doctor-blade coating process, the morphology, composition, and the surface electronic structure of the MoOx HIL could be tailored. A high-quality MoOx film with optimized charge injection was obtained, based on which all-solution-processed highly efficient red-emitting QD-LEDs were realized by using a low-cost doctor-blade coating technique under ambient conditions. The red QD-LEDs exhibited the maximum current efficiency and external quantum efficiency of 16 cd/A and 15.1%, respectively. Moreover, the lifetime of red devices initializing at 100 cd/m2 was 3236 h under ambient conditions, which is about twice as long as those with a conventional poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) H...