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Designing the optimum cathode configuration for lithium−sulfur (Li−S) batteries has held tremendous scientific momentum to achieve high energy density, fast reaction kinetics, and superior cycle retention. Herein, a self-standing and flexible PPy@rGO/CNTs (PCG) paper as sulfur host is constructed by integrating multiwalled carbon nanotubes into polypyrrole@reduced graphene oxide hybrid structure, rooted from in situ redox reaction and spontaneous assembly of pyrrole and graphene oxide. The three-dimensional (3D) corrugated papery frameworks with carbon nanotube (CNT) pillars deliver a highly conducting pathway for electron and ion transfer. Theoretical calculations indicate that ample nitrogen-and oxygen-containing functional groups can form strong polar−polar interaction with lithium polysulfides. Thus, the assembled lightweight PCG-S electrode exhibits a high gravimetric capacity of 1201.9 mA h g −1 and retains 727.8 mA h g −1 at 0.2 C after 450 cycles, remarkable rate performance, and excellent cyclic stability with an ultralow decay rate of 0.044% per cycle during 200 cycles at 1 C. Delightedly, thanks to its unique structure, the volumetric sulfur loading amount in the flexible electrode can reach ca. 0.82 g cm −3 , which endows the cathode with an ultrahigh volumetric capacity of 975 A h L −1 at 0.2 C simultaneously. This dense monolithic paper appears to be a scalable potential for developing high-performance cathodes in emerging flexible devices.

For lithium–sulfur (Li–S) batteries, a promising candidate for future high-energy storage devices, several prominent problems still need to be solved urgently, such as limited rate capability and poor cycle life caused by the insulating nature of sulfur and the shuttle of soluble polysulfides produced during battery operation. In this work, a facile vacuum filtration method is employed to graft polyethyleneimine to reduced graphene oxide (rGO) in a “hand-in-hand” way using the amino and catechol groups from polydopamine. The resulting polymer-reinforced rGO (PPG) film is applied as a free-standing auxiliary functional layer for Li–S batteries. It has been confirmed by both theoretical calculations and experimental methods that, benefiting from the rich amine groups and oxygen-containing functional groups, the as-prepared PPG composite film shows great ability to capture polysulfides. Moreover, its high conductivity enables itself to function as a polysulfide reservoir, thus facilitating the successive reutilization of the trapped active materials and improving sulfur utilization. For this reason, the PPG film can also be regarded as a cathode material, serving as a novel “SPPG cathode” together with the pure sulfur cathode. The cell assembled with the pure sulfur cathode and the PPG auxiliary functional layer displays high reversible capacity, excellent Coulombic efficiency, and good cycling stability, suggesting that the rational auxiliary functional layer design ensures a good match with pure sulfur cathodes and shows the potential to achieve energy-dense Li–S batteries.

ObjectiveSeptoplasty has been the definitive treatment for nasal septum deviation, but its postoperative procedure may affect patients’ quality of life. While new procedures in general surgery, such as enhanced recovery after surgery (ERAS), can speed up postoperative rehabilitations to improve quality of life, it is rarely applied in the ear–nose–throat field. This study therefore aims to evaluate the application of ERAS in patients with nasal septum deviation as a means of improving perioperative outcomes.Materials and methodsFifty patients with nasal septum deviation undergoing septoplasty were randomized as ERAS or control group (25 patients in both groups). Patients were investigated for outcomes including length of stay, operating time, bleeding volume, total cost, complications, and Self-Rating Anxiety Scale (SAS) and visual analog symptom score of nasal obstruction, sleep disturbance, and head facial pain.ResultsThe preoperative anxiety in ERAS group (SAS 35.4±6.2) was lower than the control group (SAS 43.6±8.6). The anxiety levels in ERAS group (SAS 31.6±5.4) was also reduced compared to the control group (SAS 38.1±10.4) in the 3 days postsurgery, but showed no significant difference thereafter at 7 days postsurgery. In addition, the length of stay and total cost were significantly lower for the ERAS group as well. The visual analog symptom score of nasal obstruction, sleep disturbance, and head facial pain in ERAS group were all also found to be lower than the control group. The only outcomes with no significant differences were the operation time, blood volume, and complications between the groups.ConclusionOur study indicated ERAS application can reduce hospital charges and postoperative pain in septoplasty, thereby improving patient quality of life and hospital expenses at the same time.

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