Electrochemical reconstruction of non-noble metal-based heterostructure nanorod arrays electrodes for highly stable anion exchange membrane seawater electrolysis

Direct seawater electrolysis for hydrogen production has been regarded as a viable route to utilize surplus renewable energy and address the climate crisis.However,the harsh electrochemical environment of seawater,particularly the presence of aggressive Cl^(-),has been proven to be prone to parasitic chloride ion oxidation and corrosion reactions,thus restricting seawater electrolyzer lifetime.Herein,hierarchical structure(Ni,Fe)O(OH)@NiCoS nanorod arrays(NAs)catalysts with heterointerfaces and localized oxygen vacancies were synthesized at nickel foam substrates via the combination of hydrothermal and annealing methods to boost seawater dissociation.The hiera rchical nanostructure of NiCoS NAs enhanced electrode charge transfer rate and active surface area to accelerate oxygen evolution reaction(OER)and generated sulfate gradient layers to repulsive aggressive Cl^(-).The fabricated heterostructure and vacancies of(Ni,Fe)O(OH)tuned catalyst electronic structure into an electrophilic state to enhance the binding affinity of hydroxyl intermediates and facilitate the structural transformation into amorphousγ-NiFeOOH for promoting OER.Furthermore,through operando electrochemistry techniques,we found that theγ-NiFeOOH possessing an unsaturated coordination environment and lattice-oxygen-participated OER mechanism can minimize electrode Cl^(-)corrosion enabled by stabilizing the adsorption of OH*intermediates,making it one of the best OER catalysts in the seawater medium reported to date.Consequently,these catalysts can deliver current densities of 100 and 500 mA cm-2for boosting OER at minimal overpotentials of 245and 316 mV,respectively,and thus prevent chloride ion oxidation simultaneously.Impressively,a highly stable anion exchange membrane(AEM)seawater electrolyzer based on the non-noble metal heterostructure electrodes reached a record low degradation rate under 100μV h-1at constant industrial current densities of 400 and 600 mA cm-2over 300 h,which exhibits a promising future for the nonprecious and stable AEMWE in the direct seawater electrolysis industry.

Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode

High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.

Rare and lacking typical clinical symptoms of liver tumors:Four case reports

BACKGROUND Rare liver tumors(RLTs)have an extremely low likelihood of forming,and some have been recorded only in isolated cases.The lack of normal clinical symptoms in RLTs makes preoperative diagnosis extremely challenging,which results in frequent misinterpretation.The present case report helps enhance our ability to recognize and treat uncommon liver tumor disorders.CASE SUMMARY We describe four distinct examples of rare liver tumor diseases.These cases were all true cases with no conventional clinical signs or imaging findings.In all patients,hepatic occupancy was discovered on physical examination,which raised the preoperative suspicion of hepatic cancer.All tumors were surgically removed,and postoperative histology and immunohistochemistry were performed to confirm the diagnosis.The first patient had primary hepatic fibrosarcoma.The second case involved a primary hepatic neuroendocrine tumors.These two patients had malignant liver tumors,and both had extremely satisfactory surgical outcomes.The third case involved focal hepatic steatosis,and the fourth case involved a single necrotic nodule in the liver.These two patients had benign liver tumors,but they had already undergone surgery and did not require any postoperative care.CONCLUSION The number of patients with RLTs is small,and the clinical and imaging results are vague.Preoperative diagnosis is challenging,and patients are sometimes mistakenly diagnosed with liver cancer,which leads to unnecessary surgical therapy in certain individuals.

Call for knowledge systematization:An example from lithium ion batteries recycling

Scientific research is one of the primary ways to drive human civilization forward.Countless research institutions and researchers worldwide are dedicated to exploring the unknown,resulting in a flood of research findings[1].For instance,Web of Science alone collects over 10,000 academic papers on a daily basis.While each research field typically has around 10%of review articles,these mainly focus on a limited portion of the subject,failing to provide a comprehensive and real-time updated overview.As a result,researchers or students in a particular field may spend several months,or even longer,comprehending the state of research that has developed over just a few years.The lack of systematic background often leads to redundant or similar studies,which is highly detrimental to the progress of science and technology.

Stackelberg Game-Based Optimal Dispatch for PEDF Park and Power Grid Interaction under Multiple Incentive Mechanisms

The integration of photovoltaic,energy storage,direct current,and flexible load(PEDF)technologies in building power systems is an importantmeans to address the energy crisis and promote the development of green buildings.The friendly interaction between the PEDF systems and the power grid can promote the utilization of renewable energy and enhance the stability of the power grid.For this purpose,this work introduces a framework of multiple incentive mechanisms for a PEDF park,a building energy system that implements PEDF technologies.The incentive mechanisms proposed in this paper include both economic and noneconomic aspects,which is the most significant innovation of this paper.By modeling the relationship between a PEDF park and the power grid into a Stackelberg game,we demonstrate the effectiveness of these incentive measures in promoting the friendly interaction between the two entities.In this game model,the power grid determines on the prices of electricity trading and incentive subsidy,aiming to maximize its revenue while reducing the peak load of the PEDF park.On the other hand,the PEDF park make its dispatch plan according to the prices established by the grid,in order to reduce electricity consumption expense,improve electricity utility,and enhance the penetration rate of renewable energy.The results show that the proposed incentive mechanisms for the PEDF park can help to optimize energy consumption and promote sustainable energy practices.

Considerations of advanced aqueous batteries recycling:A perspective

1.Introduction Battery technology,serving as a basis for a rechargeable society,has developed rapidly over a century[1].The progress can be roughly divided into three stages,with the initial two mainly focusing on aqueous battery systems.Prior to 1859,research primarily focused on the conceptualization of batteries and the development of primary(non-rechargeable)cells[2].In the subsequent150 years,rechargeable battery technology emerged。

改良LIFT治疗复杂性肛瘘的临床疗效研究

目的比较改良经括约肌间瘘管结扎术(LIFT)和切开挂线术治疗复杂性肛瘘的临床疗效。方法将80例复杂性肛瘘患者随机分为治疗组和对照组,治疗组采用改良LIFT,对照组采用切开挂线术。对两组疗效、复发率及并发症等进行对比观察。结果两组患者在手术时间、愈合时间、术中出血量、术后创面面积、术后疼痛时间、住院时间、总有效率、术后尿潴留、术后感染、术后3个月复发、术后第7、14天疼痛和首次排便疼痛视觉模拟评分法(VAS)评分及术后肛门失禁Wexner评分比较,差异有统计学意义(P<0.05);但在术后第1天视觉VAS疼痛评分及术前肛门失禁Wexner评分比较,差异无统计学意义(P>0.05)。结论改良LIFT较传统切开挂线术治愈率高,是治疗复杂性肛瘘的有效术式。

眼眶肿瘤及瘤样病变患者699例的临床组织病理学构成分析

目的:分析眼眶肿瘤及瘤样病变的临床组织病理学构成情况。方法:回顾性系列病例研究。连续收集2010-01/2020-12天津市眼科医院眼眶病眼整形科收治的眼眶肿瘤及瘤样病变患者699例707眼的临床组织病理学资料,参考美国癌症联合会第8版眼肿瘤分期标准和WHO2018版眼部肿瘤分类标准,将诊断结果分为良性、交界性及恶性三类。将全部患者按照年龄划分为0~17、18~39、40~59和60岁及以上共4组。对各组组织病理学诊断构成情况进行分析。结果:纳入699例患者707眼中男311例316眼,女388例391眼。就诊年龄为1~84(平均39.9±2.2)岁。右侧眼眶307例,左侧眼眶384例,双侧8例。良性肿瘤及瘤样病变598例604眼(85.6%),交界性肿瘤7例7眼(1.0%),恶性肿瘤94例96眼(13.4%)。在良性肿瘤及瘤样病变中,位于前5位的依次为海绵状血管瘤(110例,15.7%),皮样囊肿(96例,13.7%),多形性腺瘤(54例,7.7%),炎性假瘤(38例,5.4%),神经鞘瘤(29例,4.1%);交界性及恶性肿瘤中,位于前5位的依次为非霍奇金淋巴瘤(42例,41.6%),孤立性纤维性肿瘤(12例,11.9%),腺样囊性癌(11例,10.9%),转移癌(9例,8.9%),横纹肌肉瘤(8例,7.9%)。在常见的眼眶良性肿瘤及瘤样病变中,海绵状血管瘤和多形性腺瘤中女性患者明显多于男性。在常见的眼眶交界性和恶性肿瘤中,非霍奇金淋巴瘤和间叶性软骨肉瘤中男性患者多于女性。0~17岁患者中最常见的良、恶性肿瘤分别是皮样囊肿和横纹肌肉瘤,18~39岁中最常见的良、恶性肿瘤分别为皮样囊肿和孤立性纤维性肿瘤,40~59岁中最常见的良、恶性肿瘤分别为海绵状血管瘤和非霍奇金淋巴瘤,60岁以上最常见的良、恶性肿瘤分别为海绵状血管瘤和非霍奇金淋巴瘤。结论:眼眶肿瘤及瘤样病变中多数为良性。其中良性肿物以海绵状血管瘤和皮样囊肿多见。恶性肿瘤以非霍奇金淋巴瘤多见。

电刺激在视网膜退行性疾病治疗中的研究进展

视网膜病变和视神经损伤导致视觉信息无法正常传递到视觉中枢,对患者的视觉功能以及生活质量产生严重影响。临床工作中常见的眼部疾病如青光眼、外伤性视神经病变、视网膜色素变性等均伴有视网膜神经元和/或视神经的退行性病变,而目前临床上常用的神经保护疗法疗效非常有限。近年研究表明,电刺激对视网膜和视神经具有神经保护和促进再生的作用。本文通过对电刺激在眼科应用的进展进行综述,总结电刺激治疗的相关机制,推动电刺激在眼科疾病研究和应用中的发展。

A review of lithium-ion battery safety concerns:The issues,strategies,and testing standards

Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fires and explosions limit their further and more widespread applications.This review summarizes aspects of LIB safety and discusses the related issues,strategies,and testing standards.Specifically,it begins with a brief introduction to LIB working principles and cell structures,and then provides an overview of the notorious thermal runaway,with an emphasis on the effects of mechanical,electrical,and thermal abuse.The following sections examine strategies for improving cell safety,including approaches through cell chemistry,cooling,and balancing,afterwards describing current safety standards and corresponding tests.The review concludes with insights into potential future developments and the prospects for safer LIBs.

Rational Construction of Hierarchically Porous Fe–Co/N-Doped Carbon/rGO Composites for Broadband Microwave Absorption

Developing lightweight and broadband microwave absorbers for dealing with serious electromagnetic radiation pollution is a great challenge.Here,a novel Fe-Co/N-doped carbon/reduced graphene oxide(Fe-Co/NC/rGO)composite with hierarchically porous structure was designed and synthetized by in situ growth of Fe-doped Cobased metal organic frameworks(Co-MOF)on the sheets of porous cocoon-like rGO followed by calcination.The Fe-Co/NC composites are homogeneously distributed on the sheets of porous rGO.The Fe-Co/NC/rGO composite with multiple components(Fe/Co/NC/rGO)causes magnetic loss,dielectric loss,resistance loss,interfacial polarization,and good impedance matching.The hierarchically porous structure of the Fe-Co/NC/rGO enhances the multiple reflections and scattering of microwaves.Compared with the Co/NC and Fe-Co/NC,the hierarchically porous Fe-Co/NC/rGO composite exhibits much better microwave absorption performances due to the rational composition and porous structural design.Its minimum reflection loss(RLmin)reaches?43.26 dB at 11.28 GHz with a thickness of 2.5 mm,and the effective absorption frequency(RL≤?10 dB)is up to 9.12 GHz(8.88-18 GHz)with the same thickness of 2.5 mm.Moreover,the widest effective bandwidth of 9.29 GHz occurs at a thickness of 2.63 mm.This work provides a lightweight and broadband microwave absorbing material while offering a new idea to design excellent microwave absorbers with multicomponent and hierarchically porous structures.

Enhancing hydrothermal stability of nano-sized HZSM-5 zeolite by phosphorus modification for olefin catalytic cracking of full-range FCC gasoline

In this study, phosphorus modification by trimethyl phosphate impregnation was employed to enhance the hydrothermal stability of nano‐sized HZSM‐5 zeolites. A parallel modification was studied by ammonium dihydrogen phosphate impregnation. The modified zeolites were subjected to steam treatment at 800 °C for 4 h (100% steam) and employed as catalysts for olefin catalyticcracking (OCC) of full‐range fluid catalytic cracking (FCC) gasoline. X‐ray diffraction, N2 physicaladsorption and NH3 temperature‐programmed desorption analysis indicated that, although significantimprovements to the hydrothermal stability of nano‐sized HZSM‐5 zeolites can be observedwhen adopting both phosphorus modification strategies, impregnation with trimethyl phosphatedisplays further enhancement of the hydrothermal stability. This is because higher structural crystallinityis retained, larger specific surface areas/micropore volumes form, and there are greaternumbers of surface acid sites. Reaction experiments conducted using a fixed‐bed micro‐reactor(catalyst/oil ratio = 4, time on stream = 4 s) showed OCC of full‐range FCC gasoline-under a fluidized‐bed reaction mode configuration-to be a viable solution for the olefin problem of FCC gasoline.This reaction significantly decreased the olefin content in the full‐range FCC gasoline feed, andspecifically heavy‐end olefins, by converting the olefins into value‐added C2–C4 olefins and aromatics.At the same time, sulfide content of the gasoline decreased via a non‐hydrodesulfurization process.Nano‐sized HZSM‐5 zeolites modified with trimethyl phosphate exhibited enhanced catalytic performance for OCC of full‐range FCC gasoline.

Role of autophagy in acute myeloid leukemia therapy

Despite its dual role in determining cell fate in a wide array of solid cancer cell lines, autophagy has been robustly shown to suppress or kill acute myeloid leukemia cells via degradation of the oncogenic fusion protein that drives leukemogenesis. However, autophagy also induces the demise of acute leukemia cells that do not express the known fusion protein, though the molecular mechanism remains elusive. Nevertheless, since it can induce cooperation with apoptosis and differentiation in response to autophagic signals, autophagy can be manipulated for a better therapy on acute myeloid leukemia.

Comparison of α particle detectors based on single-crystal diamond films grown in two types of gas atmospheres by microwave plasma-assisted chemical vapor deposition

Chemical vapor deposition(CVD)-grown diamond films have been developed as irradiation-resistant materials to replace or upgrade current detectors for use in extreme radiation environments. However, their sensitivity in practical applications has been inhibited by space charge stability issues caused by defects and impurities in pure diamond crystal materials. In this study, two high-quality CVD-grown single-crystal diamond(SCD) detectors with low content of nitrogen impurities were fabricated and characterized. The intrinsic properties of the SCD samples were characterized using Raman spectroscopy, stereomicroscopy, and X-ray diffraction with the rocking curve mode, cathode luminescence(CL), and infrared and ultraviolet-visible-near infrared spectroscopies. After packaging the detectors, the dark current and energy resolution under α particle irradiation were investigated. Dark currents of less than 5 pA at 100 V were obtained after annealing the electrodes, which is comparable with the optimal value previously reported. The detector that uses a diamond film with higher nitrogen content showed poor energy resolution, whereas the detector with more dislocations showed poor charge collection efficiency(CCE). This demonstrates that the nitrogen content in diamond has a significant effect on the energy resolution of detectors, while the dislocations in diamond largely contribute to the poor CCE of detectors.

A retrospective study of 2228 cases with eyelid tumors

AIM： To describe the histopathologic and clinical features of eyelid tumor cases from Tianjin Eye Hospital during 2002 to 2015. METHODS： In this retrospective study, a total of 2228 cases of eyelid tumors with pathologic diagnoses were enrolled. The eyelid tumors were classified into three groups according to tumor origin： epidermal, adnexal and miscellaneous, including melanocytic, neural and vascular lesions. Inflammatory tumor-like lesions were excluded. The clinical characteristics of the eyelid tumors were analyzed, including age, gender and lesion location. RESULTS： Most eyelid tumors were epidermal in origin（1080, 48.5%）, followed by miscellaneous（885, 39.7%） and adnexal tumors（263, 11.8%）. Among all the tumors, 292（13.1%） were malignant lesions, 1910（85.7%） benign and 26（1.1%） premalignant lesions. Most malignant tumors originated from epidermal cells（60.0%）, followed by adnexal cells（34.6%）. The most common malignant tumors were basal cell carcinomas（56.5%） followed by sebaceous carcinoma（34.6%）, squamous cell carcinomas（3.8%） and lymphoma/plasmocytoma（1.7%）. The benign and premalignant eyelid lesions mostly originated from epidermal cells（46.4%） followed by miscellaneous cell sources（45.2%）, including melanocytic nevus（33.8%）, seborrheic keratosis（13.7%）, squamous cell papilloma（13.0%） and epidermal cysts（11.5%）. CONCLUSION： Eyelid tumors are mostly epithelial in origin. Benign tumors are significantly more common than malignant tumors with an obvious female predominance, and the most frequent malignant tumor are basal cell carcinoma, sebaceous carcinoma and squamous cell carcinomas. The tumor clinical features varied among the different subtypes.

Effectiveness of Dinoprostone and Cook's Balloon for Labor Induction in Primipara Women at Term

Labor induction is commonly used for achieving successful vaginal delivery.This study aimed to compare the effectiveness of dinoprostone and Cook's balloon as labor-inducing agents in primipara women at term.A retrospective cohort study among primipara women was conducted in Hubei Maternity and Child Health Hospital.Basic clinical characteristics were collected.The main outcomes were vaginal delivery rate,cesarean section rate and forceps delivery rate.Obstetric and perinatal outcomes were also compared.Univariate and multivariate analyses were further performed to evaluate the predictors for vaginal delivery within 24 h.A total of 845 eligible primipara women undergoing labor induction were recruited.Of them,141 women were induced with dinoprostone(dinoprostone group,DG),and 704 with Cook's balloon(Cook's balloon group,CG).Groups were homogeneous except more women with premature rupture of membranes in DG,with gestational hypertension in CG(P<0.05).The vaginal delivery rate within 12 h was 1.98%and 16.52%in CG and DG respectively(P=0.0001).Besides,the vaginal delivery rate within 24 h was 37.62%and 52.26%in CG and DG respectively(P=0.0079).DG showed the lower rate of oxytocin augmentation,artificial rupture of membrane and postpartum hemorrhage and the shorter interval from insertion to active labor than CG(P<0.05).Multivariate regression analysis revealed that abortion history,oxytocin augmentation,artificial rupture of membrane,and obstric analgesia were independent predictors for vaginal delivery within 24 h.In conclusion,dinoprostone was more effective than Cook's balloon to induce labor and achieve vaginal birth in the sample of primipara women at term.

Mechanism of micro-wetting of highly hydrophobic coal dust in underground mining and new wetting agent development

The internal mechanism of the high hydrophobicity of the coal samples from the Pingdingshan mining area was studied through industrial,element,and surface functional group analysis.Laboratory testing and molecular dynamics simulations were employed to study the impact of three types of surfactants on the surface adsorption properties and wettability of highly hydrophobic bituminous coal.The results show that the surface of highly hydrophobic bituminous coal is compact,rich in inorganic minerals,and poorly wettable and that coal molecules are dominated by hydrophobic functional groups of aromatic rings and aliphatic structures.The wetting performance of surfactants as the intermediate carrier to connect coal and water molecules is largely determined by the interaction force between surfactants and coal(Fs-c)and the interaction force between surfactants and water(Fs-w),which effectively improve the wettability of modified coal dust via modifying its surface electrical properties and surface energy.A new type of wetting agent with a dust removal rate of 89%has been developed through discovery of a compound wetting agent solution with optimal wetting and settling performance.This paper provides theoretical and technical support for removing highly hydrophobic bituminous coal dust in underground mining.

Effect of China's Universal Two-child Policy on the Rate of Cesarean Delivery: A Case Study of a Big Childbirth Center in China

China's universal two child policy was released in October of 2015.How would this new policy influence the rate of overall cesarcan delivery(CD)in China?The objective of this paper is to investigate the trend of overall CD rate with the increase of number of multiparous women based on a big childbirth center of China(a tertiary hospital)in 2016.In this study,22530 cases from the medical record department of a big childbirth center of China from January 1 to December 31 in 2016 were entolled as research objects.Electronic health records of these selected objects were retrieved.According t0 the history of childbirth,the selected cases were divided into primiparous group containing 16340 cases and multiparous group containing 6190 cases.Chi-square test was carried out to compare the rate of CD,neuraxial labor analgesia,maternity insurance between the two groups;1-test was performed to compare the in-hospital days and gestational age at birth between the two groups.Pearson corrclation coefficient was used to evaluate the rclationship among observed monthly rate of multiparas,overall CD rate,and Elective Repeat Cesarean Delivery(ERCD)rate.The results showed that the CD rate in multiparous group was 55.46%,which was higher than that in primiparous group(34.66%,P<0.05).The rate of neuraxial labor analgesia in multiparas group was 9.29%,which was lower than that in primiparas group(35.94%,P<0.05).However,the rate of maternity insurance was higher in multiparas group(57.00%)than that in primiparas group(41.08%,P<0.05).The hospital cost and in-hospital days in multiparas group were higher,and the gcstational age at birth in multiparas group was lower than in primiparas group(P<0.05).The overall CD rate slightly dropped in the first 4 months of the year(P<0.05),then increased from 36.27%(April)to 43.21%(Dcember)(P<0.05).The rate of multiparas women and ERCD had the same trend(P<0.05).There were linear correlations among the rate of overall CD,the rate of multiparas women and the rate of ERCD rate(P<0.05).With the opening of China's two-child policy,the increasing rate of overall CD is directly related with the high rate of ERCD.Trials of Labor After Cesarean Section(TOLAC)in safe mode to reduce overall CD rate are warranted in the future.

Robust Position Anti-Interference Control for PMSM Servo System With Uncertain Disturbance

Aiming to suppress the influence of uncertain disturbances in the drive control of permanent magnet synchronous machines(PMSM),such as the parameter uncertainties and load disturbance,a robust anti-interference control for the angular position tracking control of a PMSM servo system has been proposed in this paper.During the position tracking,uncertain system disturbances being regarded as a lumped unknown term will be online observed by a nonlinear disturbance observer(NDOB),of which the influence will consequently be counteracted by a robust backstepping compensator(RBC).The asymptotical stability of proposed control scheme is analyzed and designed according to the Lyapunov stability criterion,and its convergence against the system uncertain disturbance is verified on a prototype PMSM servo platform and shows good performance in rotor angular position tracking and anti-interference.

An integrated approach to improve the performance of lean–electrolyte lithium–sulfur batteries

While the sulfur conversion reaction kinetics in Li–S batteries is nowadays improved by the use of appropriate electrocatalysts,it remains a challenge for the batteries to perform well under the lean electrolyte condition where polysulfide shuttle,electrode passivation and the loss of electrolyte due to side reactions,are aggravated.These challenges are addressed in this study by the tandem use of a polysulfide conversion catalyst and a redox–targeting mediator in a gel sulfur cathode.Specifically,the gel cathode reduces the polysulfide mobility and hence the polysulfide shuttle and the passivation of the lithium anode by the crossover polysulfides.The redox mediator restrains the deposition of inactive sulfur species in the cathode thereby enabling the Fe–N and Co–N co–doped carbon catalyst to prolong its catalytic activity.Consequently,the integrated catalytic system is able to increase the discharge capacity of high–loading (6.8 mg cm^(-2)) lean–electrolyte (4.0μL mg^(-1)) Li–S batteries from~630 to~1316 m Ah g^(-1),concurrently with an improvement of the cycle life (600 cycles with 46%capacity retention at 1.0 m A cm^(-2)).Redox mediator assisted catalysis in a gel cathode is therefore an effective strategy to extend the application of the sulfur conversion catalyst in lean electrolyte Li–S batteries.