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Phase engineering is an efficient strategy for enhancing the kinetics of electrocatalytic reactions. Herein, phase engineering was employed to prepare high‐performance phosphorous‐doped biphase (1T/2H) MoS2 (P‐BMS) nanoflakes for hydrogen evolution reaction (HER). The doping of MoS2 with P atoms modifies its electronic structure and optimizes its electrocatalytic reaction kinetics, which significantly enhances its electrical conductivity and structural stability, which are verified by various characterization tools, including X‐ray photoelectron spectroscopy, high‐resolution transmission electron microscopy, X‐ray absorption near‐edge spectroscopy, and extended X‐ray absorption fine structure. Moreover, the hierarchically formed flakes of P‐BMS provide numerous catalytic surface‐active sites, which remarkably enhance its HER activity. The optimized P‐BMS electrocatalysts exhibit low overpotentials (60 and 72 mV at 10 mA cm−2) in H2SO4 (0.5 M) and KOH (1.0 M), respectively. The mechanism of improving the HER activity of the material was systematically studied using density functional theory calculations and various electrochemical characterization techniques. This study has shown that phase engineering is a promising strategy for enhancing the H* adsorption of metal sulfides. [ABSTRACT FROM AUTHOR]

MoS2, owing to its advantages of having a sheet-like structure, high electrical conductivity, and benign environmental nature, has emerged as a candidate of choice for electrodes of next-generation supercapacitors. Its widespread use is offset, however, by its low energy density and poor durability. In this study, to overcome these limitations, flower-shaped MoS2/graphene heterostructures have been deployed as electrode materials on flexible substrates. Three-electrode measurements yielded an exceptional capacitance of 853 F g−1 at 1.0 A g−1, while device measurements on an asymmetric supercapacitor yielded 208 F g−1 at 0.5 A g−1 and long-term cyclic durability. Nearly 86.5% of the electrochemical capacitance was retained after 10,000 cycles at 0.5 A g−1. Moreover, a remarkable energy density of 65 Wh kg−1 at a power density of 0.33 kW kg−1 was obtained. Our MoS2/Gr heterostructure composites have great potential for the development of advanced energy storage devices. [ABSTRACT FROM AUTHOR]

Formamidinium lead triiodide‐based perovskite solar cells have emerged as one of the most promising candidates that can be potentially used to develop photovoltaic technologies in the future. The commercial use of perovskite solar cell modules (PSCMs) is limited as it is challenging to fabricate high‐quality, efficient, and stable large‐area perovskite light‐absorbing films. Heptadecafluorooctanesulfonic acid tetraethylammonium salt (HFSTT), containing fluorinated long alkyl chains as hydrophobic tails and sulfonic acid groups (SO3−) as hydrophilic heads, which exhibit a great synergistic potential in large‐area film uniform fabrication, crystallization orientation modulation, defect passivation, and device operation stability enhancement, are introduced. The HFSTT‐modified films exhibit a prominent (100) orientation and lower trap‐state density as well as enhanced carrier mobilities and diffusion lengths, facilitating a champion unit device with an impressive power conversion efficiency (PCE) of 23.88% (0.14 cm2) and 22.52% (1 cm2) with a low voltage deficit around 0.341 V. The unencapsulated device retains ≈70% of its initial efficiency after 1000 h under heat damping test (60 °C and ≈60% RH). Moreover, the PSCMs exhibiting PCEs of 21.05% (with notable fill factor 0.79) and 18.27% are characterized by the active areas of 25.98 and 60.68 cm2, respectively. [ABSTRACT FROM AUTHOR]

Interfacial microenvironment modulation has been proven to be a promising route to fabricate highly efficient catalysts. In this work, the lattice defect‐rich NiS2/MoS2 nanoflakes (NMS NFs) electrocatalysts are successfully synthesized by a simple strategy. Benefiting from the abundant lattice defects and modulated interfacial microenvironment between NiS2 and MoS2, the prepared NMS NFs show superior catalytic activity for water splitting. Particularly, the optimized NMS NFs (the molar ratio of Ni:Mo = 5:5) exhibit remarkable catalytic activity toward overall water splitting with a voltage of 1.60 V at 10 mA cm−2 in alkaline media, which is lower than that of the noble‐metal‐based electrocatalysts (1.68 V at 10 mA cm−2). The NMS NFs electrocatalysts also show exceptional long‐term stability (>50 h) for overall water splitting. The density functional theory results demonstrate that the injection of NiS2 into MoS2 can greatly optimize the catalytic kinetics and reduce the energy barrier for hydrogen/oxygen evolution reactions. The work does not only offer a promising candidate for a highly efficient water splitting electrocatalyst but also highlights that interfacial microenvironment modulation is a potential strategy to optimize the catalytic kinetics. [ABSTRACT FROM AUTHOR]

Porous metal sulfides/TiO2 (P‐MST) photocatalysts are successfully prepared via a low‐cost strategy. It is found that the P‐MST possesses a high crystallinity with average pore size of ≈500 nm, which greatly enhances the structural stability as well as catalytic activity. The catalytic properties of the P‐MST are examined by monitoring the degradation of rhodamine B (RhB) under visible‐light irradiation. Particularly, the optimized 7% Bi2S3–CdS–MoS2–TiO2 heterostructures exhibit a remarkable catalytic performance (i.e., the degradation of RhB of ≈98.9%) and long‐term cyclic stability (i.e., the catalytic activity of ≈91.7% even after 30 cyclic test), compared with that of other P‐MST heterostructures. The exceptional catalytic performance may be ascribed to the following benefits: i) the porous structure supplies ample carrier charge transfer channels and lots of surface reaction sites; and ii) the suitable amount of metal sulfides grown on TiO2 have contributed to significant improvement of the electrical conductivity and the light absorption capability. [ABSTRACT FROM AUTHOR]