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Abstract: Owing to the recent advance of third‐generation synchrotron radiation (SR) sources, SR‐based X‐ray techniques have been widely applied to study lithium‐ion batteries, lithium–sulfur batteries, and lithium–oxygen batteries to solve material challenges. SR‐based techniques provide high chemical and physical sensitivity and a comprehensive picture of material structure and reaction mechanisms. An in‐depth understanding of batteries is imperative for the development of future energy storage devices with enhanced electrochemical performance to meet societies' growing need for devices with high energy density. Here, recent progress in the application of SR techniques for lithium secondary batteries with a focus on several techniques, including X‐ray absorption fine structure, synchrotron X‐ray diffraction, and synchrotron X‐ray microscopy techniques is reviewed. The working principle for all characterization techniques is introduced to provide context for how the technique is used in the field of energy storage. Through discussing the utilization of SR techniques in different directions of batteries, including electrodes, electrolytes, and interfaces, the practical application strategies of techniques in batteries are clarified. By summarizing and discussing the application of SR techniques in batteries, the aim is to highlight the crucial role of SR characterization in the development of advanced energy materials. [ABSTRACT FROM AUTHOR]

Composites consisting of graphene nanosheets (GNSs) decorated with amorphous TiO 2 thin films were synthesized by an atomic layer deposition (ALD) technique. It was revealed that the TiO 2 thin films were uniformly deposited onto the worm-like GNSs. When used as anode materials in lithium ion batteries (LIBs), the TiO 2 –GNS composites deliver a stable capacity of ~ 140 mAh g − 1 after 100 cycles at a specific current of 100 mA g − 1 as well as superior rate capability, accounting for a sustainable 95 mAh g − 1 capacity at a specific current of 1200 mA g − 1 . It is believed that the remarkable electrochemical performance lied in the unique features of the composites, i.e., the amorphous nature of the TiO 2 films and the large surface area of GNSs. The former rendered short Li + diffusion pathways in TiO 2 thin film, while the latter offered excellent electronic conductivity as well as a large intimate contact area between the electrolyte and TiO 2 . This work laid a venue for designing new electrodes for high-performance LIBs. [ABSTRACT FROM AUTHOR]

The electrochemical reaction kinetics of the porous core–shell structured Ni/NiO anode for Li ion battery application is systematically investigated by monitoring the electrochemical impedance evolution for the first time. The electrochemical impedance under prescribed condition is measured by using impedance spectroscopy in equilibrium conditions at various depths of discharge (DOD) during charge–discharge cycles. The Nyquist plots of the binder-free porous Ni/NiO electrode are interpreted with a selective equivalent circuit composed of solution resistance, solid electrolyte interphase (SEI) film, charge transfer and solid state diffusion. The impedance analysis shows that the change of charge transfer resistance is the main contribution to the total resistance change during discharge, and the surface configuration of the obtained electrode may experience significant change during the first two cycles. Meanwhile, the increase of internal resistance reduced the utilization efficiency of the active material may be another convincing factor to increase the irreversible capacity. In addition, the impedance evolution of the as-prepared electrode during charge–discharge cycles reveals that the slow growth of the SEI film is responsible for the capacity fading after long term cycling. As a result, several strategies are summarized to optimize the electrochemical performances of transition metal oxide anodes for lithium ion batteries. [ABSTRACT FROM AUTHOR]

A sol–gel method was employed to synthesize LiMn 2 O 4 cathode for lithium ion batteries. Calcination treatment with citric acid results in the reduction of external active materials of the cathode, finally a novel layer coating of MnO was proposed on the surface of LiMn 2 O 4 . The structures and morphologies of the as-prepared samples were characterized by XRD, Raman, SEM and HRTEM techniques. It was found that the reaction between LiMn 2 O 4 and citric acid derived carbon occurred during coating process, and the resultant layer was verified to be MnO uniformly coated onto the cathode. Electrochemical performances show that the amount of coating exhibits a significant effect on LiMn 2 O 4 performance, and the optimized MnO coating could exhibit improved battery performance of the LiMn 2 O 4 cathode. The obtained improvement is attributed to decreased Mn dissolution into electrolyte upon cycling resulting from the MnO coating. [ABSTRACT FROM AUTHOR]

Lithium phosphorus oxynitride (LiPON) solid state amorphous film electrolytes were synthesized by ion beam assisted deposition (IBAD) using Li 3 PO 4 target under nitrogen reactive plasma. IBAD presents an advantage of controllable nitrogen content of the films by adjusting N 2 and Ar flow ratio. X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), nanoindenter, and profiler were employed to characterize LiPON films. Our results indicate that the film at N 2 and Ar flow ratio of 1:8 showed the best surface morphology and mechanical properties. The highest N atomic percentage of 2.32% was also obtained at this synthesis circumstance, and the resultant LiPON film electrolyte showed higher ionic conductivity of 4.5 × 10 −6 S/cm at room temperature, as well as the highest hardness of 6.8 GPa and the lowest compressive stress of 147.2 MPa. It is believed that as-prepared LiPON solid state electrolyte film optimized can effectively prevent delamination from electrodes, showing some promising application in thin film lithium ion batteries. [ABSTRACT FROM AUTHOR]

Lithium phosphorus oxynitride (LiPON) solid-state electrolyte films were synthesized by ion beam assisted deposition (IBAD) system from Li 3 PO 4 target in nitrogen reactive plasma. Extensive measurements were taken to investigate the change in structural characteristics caused by beam current as well as the effects on mechanical properties of LiPON films. The existence of the triply coordinated nitrogen atoms in structure of LiPON films induced by ion beam bombardment was proved by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), which can produce the positive effects on Li + mobility. Analysis of nanoindentation indicated that the hardness and elastic modulus of LiPON solid-state electrolyte films varies with the beam current. The highest hardness of 5.8 GPa and the highest critical fracture load of 3.01 mN with lower compressive stress occurred at equal atomic percentage of nitrogen and phosphorus, i.e. N/P = 1 at the beam current of 18 mA. The higher hardness and lower stress are important parameters to prevent LiPON solid-state electrolyte films delamination from electrodes, which is crucial in evaluating the electrochemical performance of thin-film lithium ion battery. [ABSTRACT FROM AUTHOR]

A rutile and anatase mixed crystal phase of nano-rod TiO 2 and TiO 2 –reduced graphene oxide (TiO 2 –RGO) nanocomposites with small particle size were prepared via a facile hydrothermal approach with titanium tetrabutoxide and graphene oxide as the precursor. Hydrolysis of titanium tetrabutoxide and mild reduction of graphene oxide were simultaneously carried out. Compared with traditional multistep methods, a novel green synthetic route to produce TiO 2 –RGO without toxic solvents or reducing agents was employed. TiO 2 –RGO as anode of lithium ion batteries was characterized by extensive measurements. The nanocomposites exhibited notable improvement in lithium ion insertion/extraction behavior compared with TiO 2 , indicating an initial irreversible capacity and a reversible capacity of 295.4 and 112.3 mA h g −1 for TiO 2 –RGO after 100 cycles at a high charge rate of 10 C. The enhanced electrochemical performance is attributed to increased conductivity in presence of reduced graphene oxide in TiO 2 –RGO, a rutile and anatase mixed crystal phase of nano-rod TiO 2 /GNS composites, small size of TiO 2 particles in nanocomposites, and enlarged electrode–electrolyte contact area, leading to more electroactive sites in TiO 2 –RGO. [ABSTRACT FROM AUTHOR]

Amorphous solid‐state electrolytes (SSEs) play a pivotal role as fundamental components within all‐solid‐state lithium batteries, yet their understanding lags behind that of crystalline materials. In this work, a novel amorphous SSE 5Li2S‐3SiS2 (mol %) with a high ionic conductivity of 1.2 mS cm−1 is first reported. The silicon and sulfur atoms in the edge‐sharing Si2S64− are less attracted to lithium compared to the SiS44− anion, which is expected to facilitate the lithium ions conduction in SSEs. More importantly, the relationship between the material properties and local structure in the amorphous thiosilicate SSEs is revealed, particularly highlighting the desirable edge‐sharing local structure. The Si2S64− presents better stability with Li metal. This work offers an important guideline in the development of anion frameworks in amorphous sulfide SSEs for high‐performance all‐solid‐state lithium metal batteries. [ABSTRACT FROM AUTHOR]

NPSC represents CDDP and Bmi-1 siRNA co-loaded calcium phosphate nanoparticles with asymmetric lipid bilayer coating. The nanoparticles target tumor cells through EPR effect. The combination of CDDP and Bmi-1 siRNA in nano-delivery system inhibit cell proliferation and tumor growth in HepG2 xenograft tumor model. Bmi-1 is a gene related to malignant transformation in hepatocellular carcinoma (HCC). The liver cancer cells developed the ability to tolerate CDDP treatment with the elevation of Bmi-1. Bmi-1 is also an oncogene promoting malignance of tumor and an anti-cancer target in many studies. Herein, a biocompatible nanocarrier was designed in the study to deliver a chemotherapeutical agent CDDP and Bmi-1 siRNA to kill cancer cells and silence drug resistance related gene simultaneously. Calcium phosphate (CaP) was applied to coat both nanoplatin cores and siRNA as a shell for the purpose of delivering cargos to the cytosol of the tumor cells. Nanoplatin and siRNA co-loaded CaP nanoparticles (NPSC) enhanced cell uptake of CDDP and showed elevated drug accumulation in tumor. NPSC achieved considerable anti-cancer efficacy and counter-regulated drug tolerance, therefore, warranted a further investigation as a novel therapeutic nanosystem to improve cancer therapy. [ABSTRACT FROM AUTHOR]

Osteosarcoma is the bone tumor that most commonly affects children and teenagers with low survival rate because of metastatic relapse or recurrence. Cisplatin is a first-line chemotherapy for osteosarcoma. However, severe side effects limit its use in clinic. Selenium (Se) is an anticarcinogen that can protect normal tissues from side effects of chemotherapy. In this study, nanoparticles were used to co-deliver cisplatin and Se in a synergistic combination. Se-doped and lipid-coated calcium carbonate nanoparticles loaded with cisplatin (Pt/Se@CaCO 3 NPs) were prepared by a reverse microemulsion method. The NPs delivered cisplatin and Se to tumour cells at an optimal synergistic ratio of 1:1 (mol/mol) both in vitro and in an osteosarcoma xenograft model. These results demonstrate that Pt/Se@CaCO 3 NPs have great prospects for the osteosarcoma therapy. [ABSTRACT FROM AUTHOR]

This paper presents the reverse priority impedance control of manipulators with reference to redundant robots of a given task. The reverse priority kinematic control of redundant manipulators is first expressed in detail. The motion in the joint space is derived following the opposite order compared with the classical task priority–based solution. Then the Cartesian impedance control is combined with the reverse priority impedance control to solve the reverse hierarchical impedance controlled, so that the Cartesian impedance behavior can be divided into the primary priority impedance control and the secondary priority impedance control. Furthermore, the secondary impedance control task will not disturb the primary impedance control task. The motion in the joint space is affected following the opposite order and working in the corresponding projection operators. The primary impedance control tasks are implemented at the end, so as to avoid the possible deformations caused by the singularities occurring in the secondary impedance control tasks. Hence, the proposed reverse priority impedance control of manipulator can achieve the desired impedance control tasks with proper hierarchy. In this paper, the simulation experiments of the manipulator will verify the proposed reverse priority control algorithm. [ABSTRACT FROM AUTHOR]

Owing to the intriguing luminescence properties, Eu2+ is one of the most desirable activators for next‐generation lighting devices. Yet the application of Eu2+‐doped phosphors is limited because of the drawback of inferior luminescence efficiency. Understanding of this issue is generally from perspectives of frame structural rigidity and electronic band structure, while the lack of persuasiveness of this paradigm is frequently noticed. Herein, the analysis is conducted from a fresh view to investigate the outstanding luminescence properties of Eu2+‐doped SrMgP2O7 owning the narrow‐band emission and near‐unity quantum yield. The structural rigidity of materials is elaborately evaluated, and the influence of ionization on the luminescence efficiency of material is carefully discussed. Efforts are also made to assess the effect of vibronic coupling on 4f−5d transition of Eu2+ and clarify the excitation energy transfer route by using X‐ray spectroscopy. Based on these discussions, the synergy of weak electron−vibration interaction and inactive ionization causes the suppression of Eu2+ luminescence loss, which is associated with highly rigid local coordination and strong binding of Eu2+ to its valence electrons in the system, respectively. This work provides insight into the luminescence mechanism of Eu2+, which benefits the exploration of novel phosphors with superior luminescence features. [ABSTRACT FROM AUTHOR]

Numerous efforts are made to improve the reversible capacity and long‐term cycling stability of Li‐S cathodes. However, they are susceptible to irreversible capacity loss during cycling owing to shuttling effects and poor Li+ transport under high sulfur loading. Herein, a physically and chemically enhanced lithium sulfur cathode is proposed to address these challenges. Additive manufacturing is used to construct numerous microchannels within high sulfur loading cathodes, which enables desirable deposition mechanisms of lithium polysulfides and improves Li+ and e‐ transport. Concurrently, cobalt sulfide is incorporated into the cathode composition and demonstrates strong adsorption behavior toward lithium polysulfides during cycling. As a result, excellent electrochemical performance is obtained by the design of a physically and chemically enhanced lithium sulfur cathode. The reported electrode, with a sulfur loading of 8 mg cm‐2, delivers an initial capacity of 1118.8 mA h g‐1 and a reversible capacity of 771.7 mA h g‐1 after 150 cycles at a current density of 3 mA cm‐2. This work demonstrates that a chemically enhanced sulfur cathode, manufactured through additive manufacturing, is a viable pathway to achieve high‐performance Li‐S batteries. [ABSTRACT FROM AUTHOR]

Solid‐state electrolytes (SEs) with high anodic (oxidation) stability are essential for achieving all‐solid‐state Li‐ion batteries (ASSLIBs) operating at high voltages. Until now, halide‐based SEs have been one of the most promising candidates due to their compatibility with cathodes and high ionic conductivity. However, the developed chloride and bromide SEs still show limited electrochemical stability that is inadequate for ultrahigh voltage operations. Herein, this challenge is addressed by designing a dual‐halogen Li‐ion conductor: Li3InCl4.8F1.2. F is demonstrated to selectively occupy a specific lattice site in a solid superionic conductor (Li3InCl6) to form a new dual‐halogen solid electrolyte (DHSE). With the incorporation of F, the Li3InCl4.8F1.2 DHSE becomes dense and maintains a room‐temperature ionic conductivity over 10−4 S cm−1. Moreover, the Li3InCl4.8F1.2 DHSE exhibits a practical anodic limit over 6 V (vs Li/Li+), which can enable high‐voltage ASSLIBs with decent cycling. Spectroscopic, computational, and electrochemical characterizations are combined to identify a rich F‐containing passivating cathode‐electrolyte interface (CEI) generated in situ, thus expanding the electrochemical window of Li3InCl4.8F1.2 DHSE and preventing the detrimental interfacial reactions at the cathode. This work provides a new design strategy for the fast Li‐ion conductors with high oxidation stability and shows great potential to high‐voltage ASSLIBs. [ABSTRACT FROM AUTHOR]

Polymer binders that combine active materials with conductive agents have played a critical role in maintaining the structural integrity of phosphorus anodes with a huge volume change upon sodiation/desodiation. Herein, the role of binders on the structural/chemical stability of phosphorus/carbon anode is spectroscopically uncovered through unexpected mechanism. Surprisingly, the selection of different binders is found to determine the oxidation degree of active phosphorus in various electrodes, which correlate well with their electrochemical properties. At a high oxidation degree, the electrode applying a conventional poly(vinylidene difluoride) binder displays the worst electrochemical properties, while the electrode using a sodium alginate binder delivers the best electrochemical performance (a highly reversible capacity of 1064 mAh g−1 with a 90.1% capacity retention at 800 mA g−1 after 200 cycles and an outstanding rate capability of 401 mAh g−1 at 8000 mA g−1) for its negligible oxidation. Additionally, the emergence/decomposition of surface intermediates, including (PO2)3− and (PO4)3− species, are observed in the discharging/charging processes via the ex situ P K‐edge X‐ray absorption spectroscopies. This novel discovery of the unique role of binders in phosphorus anodes, not only provides an opportunity to ameliorate their electrochemical properties, but also enables their practical applications in high‐energy sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

The application of Li‐S batteries is hindered by low sulfur utilization and rapid capacity decay originating from slow electrochemical kinetics of polysulfide transformation to Li2S at the second discharge plateau around 2.1 V and harsh shuttling effects for high‐S‐loading cathodes. Herein, a cobalt‐doped SnS2 anchored on N‐doped carbon nanotube (NCNT@Co‐SnS2) substrate is rationally designed as both a polysulfide shield to mitigate the shuttling effects and an electrocatalyst to improve the interconversion kinetics from polysulfides to Li2S. As a result, high‐S‐loading cathodes are demonstrated to achieve good cycling stability with high sulfur utilization. It is shown that Co‐doping plays an important role in realizing high initial capacity and good capacity retention for Li‐S batteries. The S/NCNT@Co‐SnS2 cell (3 mg cm−2 sulfur loading) delivers a high initial specific capacity of 1337.1 mA h g−1 (excluding the Co‐SnS2 capacity contribution) and 1004.3 mA h g−1 after 100 cycles at a current density of 1.3 mA cm−2, while the counterpart cell (S/NCNT@SnS2) only shows an initial capacity of 1074.7 and 843 mA h g−1 at the 100th cycle. The synergy effect of polysulfide confinement and catalyzed polysulfide conversion provides an effective strategy in improving the electrochemical performance for high‐sulfur‐loading Li‐S batteries. The S/NCNT@Co‐SnS2 material acts as not only an effective shuttle‐suppressing shield for polysulfide but also an electrocatalyst in improving sulfur utilization and cycling stability for high‐sulfur‐loading lithium‐sulfur batteries. Therefore, it maintains 1004.3 mA h g−1 after 100 cycles at a current density of 1.3 mA cm−2. [ABSTRACT FROM AUTHOR]

A competitive complexation strategy has been developed to construct a novel electrocatalyst with Zn‐Co atomic pairs coordinated on N doped carbon support (Zn/CoN‐C). Such architecture offers enhanced binding ability of O2, significantly elongates the O−O length (from 1.23 Å to 1.42 Å), and thus facilitates the cleavage of O−O bond, showing a theoretical overpotential of 0.335 V during ORR process. As a result, the Zn/CoN‐C catalyst exhibits outstanding ORR performance in both alkaline and acid conditions with a half‐wave potential of 0.861 and 0.796 V respectively. The in situ XANES analysis suggests Co as the active center during the ORR. The assembled zinc–air battery with Zn/CoN‐C as cathode catalyst presents a maximum power density of 230 mW cm−2 along with excellent operation durability. The excellent catalytic activity in acid is also verified by H2/O2 fuel cell tests (peak power density of 705 mW cm−2). Discrete zinc/cobalt bimetallic sites were supported on N‐doped carbon (Zn/CoN‐C) through a competitive complexation stretegy. The as‐prepared Zn/CoN‐C catalyst exhibits outstanding ORR performance in both alkaline and acid conditions, and the assembled Zn–air batteries and H2/O2 fuel cell show excellent power density and stability, which demonstrate suitability for practical applications. [ABSTRACT FROM AUTHOR]

A competitive complexation strategy has been developed to construct a novel electrocatalyst with Zn‐Co atomic pairs coordinated on N doped carbon support (Zn/CoN‐C). Such architecture offers enhanced binding ability of O2, significantly elongates the O−O length (from 1.23 Å to 1.42 Å), and thus facilitates the cleavage of O−O bond, showing a theoretical overpotential of 0.335 V during ORR process. As a result, the Zn/CoN‐C catalyst exhibits outstanding ORR performance in both alkaline and acid conditions with a half‐wave potential of 0.861 and 0.796 V respectively. The in situ XANES analysis suggests Co as the active center during the ORR. The assembled zinc–air battery with Zn/CoN‐C as cathode catalyst presents a maximum power density of 230 mW cm−2 along with excellent operation durability. The excellent catalytic activity in acid is also verified by H2/O2 fuel cell tests (peak power density of 705 mW cm−2). [ABSTRACT FROM AUTHOR]

Multidrug resistance to chemotherapeutic drugs is a major obstacle to breast cancer treatment. In this study, doxorubicin (DOX) and imatinib (IM) were co-loaded into folate receptor targeted (FR-targeted) pH-sensitive liposomes (denoted as FPL-DOX/IM) to fulfill intracellular acid-sensitive release and reverse drug resistance. FPL-DOX/IM could maintain stability in blood circulation with approximate diameters of 100 nm and rapidly release encapsulated drugs in tumor acidic microenvironment. Moreover, the IM in combination therapy could overcome chemoresistance associated with DOX effectively by inhibiting ABC transporter function and improving chemotherapy sensitivity. The designed liposomes co-loaded with DOX and IM significantly enhanced anti-tumor effects both in vitro and in vivo . These findings suggest that FPL-DOX/IM provides a novel strategy to improve chemotherapeutic efficacy against MDR tumors. [ABSTRACT FROM AUTHOR]

The hierarchical V 2 O 5 nanofibers cathode materials with diameter of 200–400 nm are successfully synthesized via an electrospinning followed by annealing. Powder X-ray diffraction (XRD) pattern confirms the formation of phase-pure product. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) obviously display the hierarchical porous nanofibers constructed by attached tiny vanadium oxide nanoplates. Electrochemical behavior of the as-prepared product is systematically studied using galvanostatic charge/discharge testing, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). It turns out that in comparison to the commercial V 2 O 5 and other unique nanostructured materials in the literature, our V 2 O 5 nanofibers show much enhanced lithium storage capacity, improved cyclic stability, and higher rate capability. After 100 cycles at a current density of 800 mA g −1 , the specific capacity of the V 2 O 5 nanofibers retain 133.9 mAh g −1 , corresponding to high capacity retention of 96.05%. More importantly, the EIS at various discharge depths clearly reveal the kinetics process of the V 2 O 5 cathode reaction with lithium. Based on our results, the possible approach to improve the specific capacity and rate capability of the V 2 O 5 cathode material is proposed. It is expected that this study could accelerate the development of V 2 O 5 cathode in rechargeable lithium ion batteries. [ABSTRACT FROM AUTHOR]

• Cisplatin treatment caused ROS elevation and thereby HIF-1 expression. • HIF-1-regulated pathways were responsible for acquired cisplatin resistance. • Reducing ROS level to prevent HIF-1 activation could combat drug-resistance. • Nano-Se was demonstrated to scavenge ROS and thereby reverse drug-resistance. • Cisplatin-doped Nano-Se was prepared in a facile one-pot synthesis method. The clinical efficacy of cisplatin (DDP) treatment is largely limited by cisplatin resistance, which is related to the activation of hypoxia-inducible factor 1 (HIF-1). The HIF-1 activation can be induced by low oxygen availability as well as chemotherapeutics in a reactive oxygen species (ROS) dependent manner. Here, instead of the traditional ROS elevation strategy, we designed a chitosan-coated selenium/DDP (CSP) nanoparticle to deplete ROS for circumventing acquired cisplatin resistance. The antioxidative selenium nanoparticles were demonstrated to eliminate cisplatin-induced ROS, and further prevent HIF-1 activation accompanied with cisplatin treatment. A series of cisplatin resistance-associated proteins including glutamate-cysteine ligase modifier subunit (GCLM) and multidrug resistance-associated proteins (MRPs) expression were downregulated in a HIF-1α-dependent manner. And in vitro and in vivo experiments showed that CSP nanoparticles exhibited enhanced antitumor efficacy to cisplatin-resistant A549/DDP lung cancer cell lines and xenografts. These results proved that the side effects of treatment-induced ROS in HIF-1 activation and cisplatin-resistance could be significantly reversed by a selenium nanovehicle, which may possess broader applications in ROS-mediated resistance or other ROS-involved diseases. [ABSTRACT FROM AUTHOR]

The Li‐rich layer‐structured oxides are regarded as one of the most promising cathode materials for their high energy density but suffer from severe problems such as capacity fading, poor rate performance, and continuous potential dropping. These issues are addressed here by surface doping of niobium (Nb) and other heavy ions in a Li‐rich Mn‐based layered oxide, Li1.2Mn0.54Ni0.13Co0.13O2. The doped ions are verified to be located in the Li‐layer near the oxide surface; they bind the slabs via the strong NbO bonds and "inactivate" the surface oxygen, enhancing the structural stability. The specific capacity of the modified oxide reaches 320 mAh g−1 in the initial cycle, 94.5% of which remains after 100 cycles. More importantly, the average discharge potential drops only by 136 mV in this process. The findings of this study illustrate the importance of inactivating the surface oxygen in suppressing the cation mixing in the bulk, providing an effective strategy for designing high‐performance Li‐rich cathode materials. A new strategy is proposed to improve the electrochemical and thermal performance of Li‐rich layered oxide by niobium (Nb) surface doping. Transformation from layered to rocksalt‐like structure is stopped and the potential becomes stable by inactivating surface oxygen in Li1.2Mn0.54Ni0.13Co0.13O2. These findings serve as a revelation for the development of Li‐rich layered materials with mitigated potential decay and a longer lifespan. [ABSTRACT FROM AUTHOR]