High‐voltage LiCoO2 delivers a high capacity but sharp fading is a critical issue, and the capacity decay mechanism is also poorly understood. Herein, we clarify that the escape of surface oxygen and Li‐insulator Co3O4 formation are the main causes for the capacity fading of 4.6 V LiCoO2. We propose the inhibition of the oxygen escape for achieving stable 4.6 V LiCoO2 by tailoring the Co3d and O2p band center and enlarging their band gap with MgF2 doping. This enhances the ionicity of the Co−O bond and the redox activity of Co and improves cation migration reversibility. The inhibition of oxygen escape suppresses the formation of Li‐insulator Co3O4 and maintains the surface structure integrity. Mg acts as a pillar, providing a stable and enlarged channel for fast Li+ intercalation/extraction. The modulated LiCoO2 shows almost zero strain and achieves a record capacity retention at 4.6 V: 92 % after 100 cycles at 1C and 86.4 % after 1000 cycles at 5C.

Oxygen release and irreversible cation migration are the main causes of voltage fade in Li-rich transition metal oxide cathode. But their correlation is not very clear and voltage decay is still a bottleneck. Herein, we modulate the oxygen anionic redox chemistry by constructing Li2ZrO3 slabs into Li2MnO3 domain in Li1.21Ni0.28Mn0.51O2, which induces the lattice strain, tunes the chemical environment for redox-active oxygen and enlarges the gap between metallic and anionic bands. This modulation expands the region in which lattice oxygen contributes capacity by oxidation to oxygen holes and relieves the charge transfer from anionic band to antibonding metal–oxygen band under a deep delithiation. This restrains cation reduction, metal–oxygen bond fracture, and the formation of localized O2 molecule, which fundamentally inhibits lattice oxygen escape and cation migration. The modulated cathode demonstrates a low voltage decay rate (0.45 millivolt per cycle) and a long cyclic stability.

The effect of oxygen vacancy and spinel phase integration on anionic and cationic redox in Li-rich cathode materials was unraveled.

The oxygen redox reaction in lithium-rich layered oxide battery cathode materials generates extra capacity at high cell voltages (i.e., >4.5 V). However, the irreversible oxygen release causes transition metal (TM) dissolution, migration and cell voltage decay. To circumvent these issues, we introduce a strategy for tuning the Coulombic interactions in a model Li-rich positive electrode active material, i.e., Li1.2Mn0.6Ni0.2O2. In particular, we tune the Coulombic repulsive interactions to obtain an adaptable crystal structure that enables the reversible distortion of TMO6 octahedron and mitigates TM dissolution and migration. Moreover, this strategy hinders the irreversible release of oxygen and other parasitic reactions (e.g., electrolyte decomposition) commonly occurring at high voltages. When tested in non-aqueous coin cell configuration, the modified Li-rich cathode material, combined with a Li metal anode, enables a stable cell discharge capacity of about 240 mAh g−1 for 120 cycles at 50 mA g−1 and a slower voltage decay compared to the unmodified Li1.2Mn0.6Ni0.2O2.

In this study, an energy efficient Li-ion battery anode composite system based on silicon nanoparticles and graphene has been demonstrated, wherein the raw materials were obtained from waste by-products such as rice husk.

We investigated the effect of single and multidopants on the thermoelectrical properties of host ZnO films. Incorporation of the single dopant Ga in the ZnO films improved the conductivity and mobility but lowered the Seebeck coefficient. Dual Ga- and In-doped ZnO thin films show slightly decreased electrical conductivity but improved Seebeck coefficient. The variation of thermoelectric properties is discussed in terms of film crystallinity, which is subject to the dopants' radius. Small amounts of In dopants with a large radius may introduce localized regions in the host film, affecting the thermoelectric properties. Consequently, a 1.5 times increase in power factor, three times reduction in thermal conductivity, and 5-fold enhancement in the figure of merit ZT have been achieved at 110 °C. The results also indicate that the balanced control of both electron and lattice thermal conductivities through dopant selection are necessary to attain low total thermal conductivity.

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In this corrigendum, we present corrections to the paper 'Oxygen vacancy-induced magnetic moment in edgesharing CuO 2 chains of Li 2 CuO 2−δ ' (2017 New J. Phys. 19 023206) by Shu et al. Equation (7) shown in the paper is wrong due to copying error, which has been corrected following the referenced source with modification. The J 1 values for Li 2 CuO 2−δ (δ ∼ 0 and 0.16) shown in table 6 should be doubled for a consistent comparison based on the definition of used Hamiltonian.(1) Correction to equation (7): Equation (7) shown in the paper by Shu et al is wrong [1], the correct one with proper units must follow the original form of equation (3) in [2] by Takeda et al with an added z J   term as z J z J Ng 1 2 . AbstractLi 2 CuO 2 is a typical charge transfer insulator with CuO 2 chains that are composed of edge-shared CuO 4 plaquettes. The existence of oxygen vacancies for single crystals prepared under various oxygen partial pressures has been confirmed by the chemical and thermogravimetric analyses. The puzzling discovery of extra magnetic moment near the oxygen site by earlier neutron scattering studies has been verified by a thorough Curie-Weiss law analysis of spin susceptibilities, and resolved quantitatively with a molecular orbital model of edge-sharing CuO 2 chains containing oxygen vacancies.where ¢ = z 2 and  = z 4 correspond to the coordination numbers for ¢ J and  J , respectively, as shown in figure 9(b). With the defined = ¢  A J J ratio, the best fitting parameters of χ(T) for δ∼0.16 and 0 are summarized in table 5. The signs of --¢  J J J indicate that the intra-chain coupling (J) is FM, inter-chain coupling within the ab-plane ( ¢ J ) is FM, and the inter-chain coupling along the diagonal direction (  J ) is AF, which is consistent to the neutron diffraction results as illustrated in figure 9(a) [2, 6]. These fitted intra-chain and interchain coupling constants are comparable to those obtained using the J 1 -J 2 -J c model and molecular quantum chemistry calculation also [14,23]. Figure 9. (a) The magnetic couplings J i (i=1-6) for the antiferromagnetically FM chains in Li 2 CuO 2 . The spin structure is plotted based on the neutron diffraction results proposed by Sapina et al [2] and Chung et al [6]. (b) A simplified inter-chain coupling model of FM chains projected in the ac-plane is shown, where ¢ J and  J roughly correspond to the averages of J 3 4 and J 5 6 shown in (a), respectively. Table 5. The intra-chain (J) and inter-chain ( ¢ J ,  J ) couplings for Li 2 CuO 2−δ single crystal samples of δ∼0.16 and 0 are extracted from the fitting of temperature-dependent spin susceptibility data with equation (7). The nearest-neighbor ¢ J and the next-nearest-neighbor  J are depicted in figure 9(b) with defined ratio of = ¢  A J J . It is interesting to find that the fitted value of = ¢  A J J (table 5) is nearly equal to the ratio of  ¢ d d J J as 7 Å Å ( )  = ¢ ~=  ¢ A J J d d 5.240 3.662 1.431, 9 J J +50 * Defined˜( ) = J J 1 5 and˜( ) = J J 2 6 but missed both J 3 and J 4