the nonconstant renewable energy and achieve a stable power output for practical usage. [1,2] As an alternative solution, electrochemical energy storage (EES) systems, i.e., batteries and supercapacitors, can realize the electrical energy storage via the interconversion of chemical and electrical energy. Although EES devices have been widely used in portable electronic devices, electrical vehicles, and even electric grid in the past decades, they still suffer from the limited energy density and cycling stability. [3][4][5] For instance, to realize the driving range of at least 500 km for lithium-ion battery (LIB) powered electric vehicles, the energy densities of 235 Wh kg −1 and 500 Wh L −1 at battery pack level are required. However, the stateof-the-art automotive LIB packs only reach 130-140 Wh kg −1 and over 210 Wh L −1 , respectively. [6,7] Therefore, numerous efforts have been devoted to searching proper active materials with satisfied electrochemical performance for EES devices.Since the successful preparation of graphene in 2004, 2D nanomaterials have attracted worldwide attention due to their unique properties. [8][9][10][11] As a typical example of graphene-like 2D nanomaterials, layered transition metal dichalcogenides (TMDs) with an X-M-X structure (M: transition metal element; X: S, Se, or Te) have shown great potential for applications in energy storage, catalysis, electronics, photonics, etc. [12][13][14] The 2D nature of layered TMD nanomaterials makes them suitable active materials for the EES due to the following aspects: i) The large specific surface area ensures a large contact area between the active materials and the electrolyte, enabling the fast "Faradaic" and "non-Faradaic" reactions at the surfaces of layered TMD nanomaterials. [15,16] ii) The under-coordinated edge sites of layered TMD nanomaterials can act as adsorption sites for metal ions and thus contribute to extra metal-ion storage capacities. [17] iii) The adjacent X-M-X layers in layered TMD nanomaterials are coupled by weak van der Waals forces. The interlayer space between layers can realize not only the fast ion diffusion, insertion and extraction, but also better material utilization during the metal-ion insertion process. [17] iv) The thin and flexible characteristics of 2D TMD nanosheets make them easy to be incorporated into flexible EES devices. [18][19][20][21] Besides the 2D structure, the tunable physical properties of layered TMD nanomaterials also bring about intriguing potential for their application in EES systems. Layered TMDs usually possess three polymorphs, i.e., 1T, 2H, and 3R, standing for trigonal, hexagonal, and rhombohedral phases, respectively. The rapid development of electrochemical energy storage (EES) systems requires novel electrode materials with high performance. A typical 2D nanomaterial, layered transition metal dichalcogenides (TMDs) are regarded as promising materials used for EES systems due to their large specific surface areas and layer structures benefiting fast ion transport. The typical ...

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Solar‐thermal water evaporation, as a promising method for clean water production, has attracted increasing attention. However, solar water evaporators that exhibit both high water vapor generation ability and anti‐oil‐fouling ability have not been reported. Here, a unique metal–organic‐framework‐based hierarchical structure, referred to as MOF‐based hierarchical structure (MHS), is rationally designed and prepared, which simultaneously displays a high solar absorption and a superhydrophilic and underwater superoleophobic surface property. As a proof‐of‐concept application, a device prepared from the MHS can achieve a high solar‐thermal water evaporation rate of 1.50 kg m−2 h−1 under 1 sun illumination. Importantly, the MHS also possesses an excellent anti‐oil‐fouling property, ensuring its superior water evaporation performance even in oil‐contaminated water. The high solar‐thermal water evaporation rate and anti‐oil‐fouling property make the MHS a promising material for the solar‐thermal water production.

Recently, crystal-phase engineering has been emerging as a promising strategy to tune the physicochemical properties of noble metal catalysts and further improve their catalytic performance. However, the synthesis of noble metal catalysts with an unconventional crystal phase as well as desired composition and morphology still remains a great challenge. Herein, a series of PdM (M = Zn, Cd, ZnCd) nanosheets (NSs) with thickness less than 5 nm have been synthesized via a facile one-pot wet-chemical method. In particular, different from the conventional face-centered cubic (fcc) phase, PdM NSs possess an unconventional face-centered tetragonal (fct) phase. As a proof-of-concept application, the fct PdZn NSs exhibit significantly enhanced mass activity and stability in ethanol oxidation reaction, compared to the pure Pd NSs and commercial Pd black catalyst.

As a source of clean energy, a reliable hydrogen evolution reaction (HER) requires robust and highly efficient catalysts. Here, by combining chemical vapor transport and Li-intercalation, we have prepared a series of 1T'-phase ReSSe ( x = 0-1) nanodots to achieve high-performance HER in acid medium. Among them, the 1T'-phase ReSSe nanodot exhibits the highest hydrogen evolution activity, with a Tafel slope of 50.1 mV dec and a low overpotential of 84 mV at current density of 10 mA cm. The excellent hydrogen evolution activity is attributed to the optimal hydrogen absorption energy of the active site induced by the asymmetric S vacancy in the highly asymmetric 1T' crystal structure.