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With an increasingly profound understanding of battery materials, strategies designed for interface protection have become more sophisticated. However, it is inherent that different materials used in electrodes and electrolytes tend to react with each other. To address this issue, this study proposes an "Electrode‐Electrolyte‐In‐One" (EEIO) concept, where a single energy storage material can serve as both electrode and solid‐state electrolyte (SSE) during its different ion storage stages. The EEIO materials of chloride ion batteries and fluorine ion batteries are preliminarily studied, establishing reasonable screening procedures and predicting their operational mechanisms. The analysis of Cl− and F− affinity indicates that the EEIO system in the anion storage batteries comprises the anode and SSE. Through comprehensive evaluation of ion binding capacity, phase transformation mechanism, electrical conductivity, and ion diffusion kinetic properties, several potential EEIO materials are identified. In the EEIO system, the material interface and the conductive‐insulation interface are separated, which solves the material compatibility problem between the anode and SSE. Furthermore, the EEIO system has an inherent correlation between the anode electrochemical reaction and the SSE decomposition reaction, ensuring that the electrochemical voltage of EEIO batteries never exceeds the decomposition voltage of SSE. Therefore, SSE in the EEIO battery has absolute electrochemical stability. [ABSTRACT FROM AUTHOR]

Monolayer 2D lateral heterostructures with high interface qualities and well‐defined structures are particularly promising in novel electronic and optoelectronic applications. However, the photoelectric responses are still very low, and the working and modulating mechanisms urgently need exploration. Here, a lateral monolayer heterojunction of WS2‐WSe2 is successfully prepared with an atomically sharp interface and a band alignment of type‐II structure. Intriguingly, this heterojunction photodetector (PD) achieves outstanding characteristics of photocurrent generation in both photovoltaic and photoconductive modes with responsivities (Rs) of 60.2/3.0 A W−1, detectivities (D*s) of 1.81/0.98 × 1012 Jones, and response times of 32.2/28.5 and 39.5/32.1 ms, respectively. Moreover, all‐inorganic CsPbBr3 quantum dots are introduced to substantially promote the photoelectric responses. Because of the favorable band alignment and large absorption of the CsPbBr3, and efficient carrier transfer, the Rs and D*s are substantially improved to 1307/141.3 A W−1 and 1.16/2.94 × 1013 Jones, respectively, with fantastic external quantum efficiencies of 3.59/0.388 × 105% and also shortened response times of 12.5/13.2 and 17.4/15.8 ms. In addition, the ambient stability is remarkably enhanced. This study demonstrates that the combination of 2D lateral heterojunction with all‐inorganic perovskite may bring up promising opportunities for developing high‐performance PDs. [ABSTRACT FROM AUTHOR]

Abstract: A route to realize strain engineering in weakly bonded heterostructures is presented. Such heterostructures, consisting of layered materials with a pronounced bond hierarchy of strong and weak bonds within and across their building blocks respectively, are anticipated to grow decoupled from each other. Hence, they are expected to be unsuitable for strain engineering as utilized for conventional materials which are strongly bonded isotropically. Here, it is shown for the first time that superlattices of layered chalcogenides (Sb2Te3/GeTe) behave neither as fully decoupled two‐dimensional (2D) materials nor as covalently bonded three‐dimensional (3D) materials. Instead, they form a novel class of 3D solids with an unparalleled atomic arrangement, featuring a distribution of lattice constants, which is tunable. A map to identify further material combinations with similar characteristic is given. It opens the way for the design of a novel class of artificial solids with unexplored properties. [ABSTRACT FROM AUTHOR]

Hierarchically structured nitrogen-doped carbon nanotube (NCNT) composites, with copper (Cu) nanoparticles embedded uniformly within the nanotube walls and cobalt oxide (Co xO y) nanoparticles decorated on the nanotube surfaces, are fabricated via a combinational process. This process involves the growth of Cu embedded CNTs by low- and high-temperature chemical vapor deposition, post-treatment with ammonia for nitrogen doping of these CNTs, precipitation-assisted separation of NCNTs from cobalt nitrate aqueous solution, and finally thermal annealing for Co xO y decoration. Theoretical calculations show that interaction of Cu nanoparticles with CNT walls can effectively decrease the work function of CNT surfaces and improve adsorption of hydroxyl ions onto the CNT surfaces. Thus, the activities of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) are significantly enhanced. Because of this benefit, further nitrogen doping, and synergistic coupling between Co xO y and NCNTs, Cu@NCNT/Co xO y composites exhibit ORR activity comparable to that of commercial Pt/C catalysts and high OER activity (outperforming that of IrO2 catalysts). More importantly, the composites display superior long-term stability for both ORR and OER. This simple but general synthesis protocol can be extended to design and synthesis of other metal/metal oxide systems for fabrication of high-performance carbon-based electrocatalysts with multifunctional catalytic activities. [ABSTRACT FROM AUTHOR]

A multi‐step synthesis approach for hierarchically structured nitrogen doped carbon nanotubes (NCNTs) is reported by Jong‐Beom Baek and co‐workers in article number 1605717. The walls are embedded uniformly with copper (Cu) nanoparticles and the outer wall surfaces are decorated with cobalt oxide (CoxOy) nanoparticles. These Cu@NCNT/CoxOy composites demonstrate high electrocatalytic activity for both oxygen reduction reaction and oxygen evolution reaction. [ABSTRACT FROM AUTHOR]