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Outstanding charge transport in molecular crystals is of great importance in modern electronics and optoelectronics. The widely adopted strategies to enhance charge transport, such as restraining intermolecular vibration, are mostly limited to organic molecules, which are nearly inoperative in 2D inorganic molecular crystals currently. In this contribution, charge transport in 2D inorganic molecular crystals is improved by integrating charge‐delocalized Se8 rings as building blocks, where the delocalized electrons on Se8 rings lift the intermolecular orbitals overlap, offering efficient charge transfer channels. Besides, α‐Se flakes composed of charge‐delocalized Se8 rings possess small exciton binding energy. Benefitting from these, α‐Se flake exhibits excellent photodetection performance with an ultrafast response rate (~5 μs) and a high detectivity of 1.08 × 1011 Jones. These findings contribute to a deeper understanding of the charge transport of 2D inorganic molecular crystals composed of electron‐delocalized inorganic molecules and pave the way for their potential application in optoelectronics. [ABSTRACT FROM AUTHOR]

The effective governance of Hg2+ in environmental wastewater is of profound significance to deal with the global pollution issues. However, the present methodologies usually only focused on a single function of either detection or removal, which encounters severe secondary pollution and cumbersome operation cost, while the integration of Hg2+ detection, removal, and recovery in one process is barely realized. In this study, an All‐In‐One photoelectrochemical system is built combining the detection, removal, and recovery of Hg2+ pollutant in a single process, by ingeniously developing a fundamental principle, namely alloying‐induced plasmonic quenching mechanism in Schottky heterostructures. Briefly, the high‐efficiency removal and recovery of Hg2+ in wastewater is realized via the favorable alloying of Hg in Ag nanoparticles that well‐dispersed on the free‐standing WO3 nanoplate networks. The formation of Ag–Hg alloy future leads to a remarkable plasmonic quenching effect of the Ag nanoparticles, which is used to modulate the photoelectrochemical singles to realize the high‐precision detection. Through this ingenious design, an ultralow Hg2+ detection limit of 0.296 nm is achieved with a broad detection range up to 12.5 µm, and meanwhile realize a removal/recovery rate of 100% in single Hg2+ solution and 97 ± 2% in industrial wastewater with multiple contamination ions. The detection and removal/recovery performance parameters reported in the study are much better as compared to the recently reported single function detection or removal/recovery systems. This work opens a fresh avenue in tackling the problem of heavy metal pollution using plasmonic Schottky heterostructure based All‐In‐One systems. [ABSTRACT FROM AUTHOR]

Zn metal anode suffers from dendrite growth and side reactions during cycling, significantly deteriorating the lifespan of aqueous Zn metal batteries. Herein, we introduced an ultrathin and ultra‐flat Sb2O3 molecular crystal layer to stabilize Zn anode. The in situ optical and atomic force microscopes observations show that such a 10 nm Sb2O3 thin layer could ensure uniform under‐layer Zn deposition with suppressed tip growth effect, while the traditional WO3 layer undergoes an uncontrolled up‐layer Zn deposition. The superior regulation capability is attributed to the good electronic‐blocking ability and low Zn affinity of the molecular crystal layer, free of dangling bonds. Electrochemical tests exhibit Sb2O3 layer can significantly improve the cycle life of Zn anode from 72 h to 2800 h, in contrast to the 900 h of much thicker WO3 even in 100 nm. This research opens up the application of inorganic molecular crystals as the interfacial layer of Zn anode. [ABSTRACT FROM AUTHOR]

2D van der Waals (vdW) magnets have opened intriguing prospects for next‐generation spintronic nanodevices. Machine learning techniques and density functional theory calculations enable the discovery of 2D vdW magnets to be accelerated; however, current computational frameworks based on these state‐of‐the‐art approaches cannot offer probability analysis on whether a 2D vdW magnet can be experimentally demonstrated. Herein, a new framework can be established to overcome this challenge. Via the framework, 2D vdW magnets with high probability for experimental demonstration are captured from materials science literature. The key to the successful establishment is the introduction of the theory of mutual information. Historical validation of predictions substantiates the high reliability of the framework. For example, half of the 30 2D vdW magnets discovered in the literature published prior to 2017 have been experimentally demonstrated in the subsequent years. This framework has the potential to become a revolutionary force for progressing experimental discovery of 2D vdW magnets. [ABSTRACT FROM AUTHOR]

The unique intermolecular van der Waals force in emerging two‐dimensional inorganic molecular crystals (2DIMCs) endows them with highly tunable structures and properties upon applying external stimuli. Using high pressure to modulate the intermolecular bonding, here we reveal the highly tunable charge transport behavior in 2DIMCs for the first time, from an insulator to a semiconductor. As pressure increases, 2D α‐Sb2O3 molecular crystal undergoes three isostructural transitions, and the intermolecular bonding enhances gradually, which results in a considerably decreased band gap by 25 % and a greatly enhanced charge transport. Impressively, the in situ resistivity measurement of the α‐Sb2O3 flake shows a sharp drop by 5 orders of magnitude in 0–3.2 GPa. This work sheds new light on the manipulation of charge transport in 2DIMCs and is of great significance for promoting the fundamental understanding and potential applications of 2DIMCs in advanced modern technologies. [ABSTRACT FROM AUTHOR]

The monoclinic GeP with large capacity, low plateau, and high initial coulombic efficiency (ICE) has been proved to be alternative anode for Li‐ion batteries. However, the heavy use of Ge raw material with its high price, hinders its further development. Herein, the Zn atom is proposed for substitution into GeP and replaces part of the Ge owing to its low price, suitable plateau, and similar radius. Interestingly, a novel Ge1−xZnxP solid solution with a wide range tunable region (0.143 < x < 0.6) is achieved, reducing the heavy use of Ge and cutting the GeP price down. More intriguingly, such Ge1−xZnxP possesses a new phase, different from monoclinic GeP, which is first verified to be a cubic system in F‐43m. Compared to semi‐conducting GeP, this cubic Ge1−xZnxP phase possesses metallic conductivity, thus enabling a better rate performance than monoclinic GeP (e.g., 881 vs 283 mAh g−1 at 2000 mA g−1), while keeping the great advantages of large capacity, low plateau, and high ICE of GeP as well. Consequently, the assembled LiCoO2//Ge1−xZnxP full cell exhibits large capacity over 1000 mAh g−1. This unique phase control strategy by atomic substitution can be easily extended to manipulate electrochemical behaviors of other multi‐phase materials toward advanced energy storage. [ABSTRACT FROM AUTHOR]

Sulfur vacancies (SVs) inherent in MoS2 are generally detrimental for carrier mobility and optical properties. Thiol chemistry has been explored for SV repair and surface functionalization. However, the resultant products and reaction mechanisms are still controversial. Herein, a comprehensive understanding on the reactions is provided by tracking potential energy surfaces and kinetic studies. The reactions are dominated by two competitive mechanisms that lead to either functionalization products or repair SVs, and the polarization effect from decorating thiol molecules and thermal effect are two determining factors. Electron-donating groups are conducive to the repairing reaction whereas electron-withdrawing groups facilitate the functionalization process. Moreover, the predominant reaction mechanism can be switched by increasing the temperature. This study fosters a way of precisely tailoring the electronic and optical properties of MoS2 by means of thiol chemistry approaches. [ABSTRACT FROM AUTHOR]

Fe3GeTe2 is a water‐ and air‐stable, metallic, and layered material. Very recently, few‐layer and single‐layer Fe3GeTe2 have been successfully exfoliated from its bulk and revealed as 2D ferromagnets (Nature2018, 563, 94; Nat. Mater. 2018, 17, 778). Here, the basal plane of Fe3GeTe2 is demonstrated to be of high electrocatalytic activity towards oxygen evolution reaction (OER) without resorting to any chemical modifications, by means of systematic density functional theory computations. The Fe3GeTe2 nanosheet preserves the metallic character of the bulk, and its 2D layered structure provides abundant exposed active sites to catalyze OER. All these unique characteristics suggest that the Fe3GeTe2 nanosheet may be an excellent catalyst for electrochemical OER. More importantly, it is found that the self‐reduction of surface hydroxyl into water can significantly reduce the overpotential for OER, which greatly boosts the OER activity. This work not only reveals new mechanisms for OER but also opens the door for the application of emerging 2D ferromagnets in the field of energy storage and conversion. [ABSTRACT FROM AUTHOR]

In contrast to conventional atomic crystals, two‐dimensional inorganic molecular crystals (2DIMCs) possess a unique crystal structure composed of small molecules held together by van der Waals force. Such distinctive structure grants them specific chemical and physical properties highly suitable for electronic and optoelectronic applications. However, the synthesis of 2DIMCs has posed significant challenges due to the inherent issues such as uncontrollable growth orientation stemming from their natural crystalline isotropy and poor stability resulting from the weak intermolecular connections. Addressing these obstacles, the preparation of large‐scale and highly‐stable 2DIMC BiBr3, and its heterostructure are reported here by developing crystallization orientation engineering strategies. This approach has successfully yielded centimeter‐scale 2DIMC BiBr3 with a clean and dense surface, showcasing exceptional long‐term air‐stability exceeding 80 days. Furthermore, the universal growth of large‐scale 2DIMC BiBr3 is demonstrated on diverse substrates, including SiO2, Al2O3, and MoS2 monolayers. Notably, the resultant 2D BiBr3/MoS2 heterostructure exhibits remarkable photoluminescence enhancement. This contribution paves a universal avenue for the mature synthesis of large‐scale 2DIMCs with superior stability, holding great promise for prompting their integration in practical electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Electrical control of atom‐thick van der Waals (vdW) ferromagnets is a key toward future magnetoelectric nanodevices; however, state‐of‐the‐art control approaches are volatile. In this work, introducing ferroelectric switching as an aided layer is demonstrated to be an effective approach toward achieving nonvolatile electrical control of 2D ferromagnets. For example, when a ferromagnetic monolayer CrI3 and ferroelectric MXene Sc2CO2 come together into multiferroic heterostructures, CrI3 is controlled by polarized states P↑ and P↓ of Sc2CO2. P↑ Sc2CO2 does not change the semiconducting nature of CrI3, but surprisingly P↓ Sc2CO2 makes CrI3 half‐metallic. Nonvolatility of the electrical switching between two oppositely ferroelectric polarized states, therefore, indirectly enables nonvolatile electrical control of CrI3 between ferromagnetic semiconductor and half‐metal. The heterointerface‐induced half‐metallicity in CrI3 is intrinsic without resorting to any chemical functionalization or external physical modification, which is rather beneficial to the practical application. This work paves the way for nonvolatile electrical control of 2D vdW ferromagnets and applications of CrI3 in half‐metal‐based nanospintronics. [ABSTRACT FROM AUTHOR]