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Molybdenum disulfide as a supercapacitor material has attracted great attention owing to its low price and high theoretical capacity. However, the low conductivity and relatively few active sites restrict its practical application. In this work, a 3D bacterial cellulose intercalated MoS2@rGO nanocomposite is fabricated via the freeze-drying method and an in situ carbonization process. The BC can prevent the stacking of rGO and expose more electrochemical active sites. Benefitting from the synergistic effect of BC and rGO, the prepared MoS2@rGO@CF-2 displays a high specific capacitance of 345 F g−1 at the current density of 0.5 A g−1. [ABSTRACT FROM AUTHOR]

MoS2 as one graphene-like 2D layered transition metal sulfide has attracted great attention. However, its application for the HER is still restricted by the poor electrical conductivity and structural restacking. In this work, we developed a facile method to prepare MoO2@MoS2 heterostructures in situ by partial conversion of MoOx into MoS2 on carbon cloth. Based on the two-time hydrothermal process, the MoS2 nanosheets can be dispersed and grow on carbon cloth. Excellent electrochemical HER activity of MoO2@MoS2/CC-2 can be achieved with a low overpotential of 115 mV at 10 mA cm−2 (η10) in 0.5 M H2SO4. Furthermore, it still shows durable electrocatalytic stability for 13 h. The outstanding electrocatalytic activity may be ascribed to the synergistic effect between the MoO2 and MoS2 heterostructures. [ABSTRACT FROM AUTHOR]

Summary: Developing cheap and abundant materials as high efficient HER catalysts to replace noble metal catalysts is urgent. Molybdenum disulfide (MoS2) as one attention‐drawing material still has an enormous limit due to the layers stacking and the lacking of active sites. Therefore, the N, P dual‐doped MoS2 on hollow carbon spheres (denoted as P‐MoS2@NCs) has been developed via template sacrifice, polymerization, and hydrothermal process. The synergistic effect between the N, P dual‐doped hollow carbon spheres, and MoS2, which has abundant active sites can enhance the electrocatalytic performance of HER. As expected, the formed P‐MoS2@NCs‐2 exhibits excellent electrochemical property for HER. The overpotential at 10 mA cm−2 and Tafel slope are as low as 147 mV (V vs RHE) and 72 mV/dec. Otherwise, it shows excellent durability in 0.5 M H2SO4. It provides a new method to develop advanced MoS2‐based catalyst for the HER. [ABSTRACT FROM AUTHOR]

Ti-based layered double hydroxides (LDHs) have enormous potential in photocatalysis, electrocatalysis, and photoelectrocatalysis. However, Ti-based LDHs are rarely reported because of the difficulties of the preparation process, in which the Ti precursors are more prone to hydrolysis into titanium hydroxide. In this work, toward robust, efficient, and earth-abundant electrocatalysts for water oxidation in alkaline environments, we have engineered Ti-doped Ni(OH) 2 nanosheet arrays on carbon cloth [Ti-Ni(OH) 2 /CC] with a facile solvothermal and surfactant-free method. The experimental tests show that the activity of Ti-Ni(OH) 2 -1/CC (∼12.5 atom % Ti substitution) is optimal among these materials. In addition, the activity is correlated with the Ti substitution ratio and reversed with higher Ti doping level (≥25 atom % Ti substitution). Therein, η 10 of Ti-Ni(OH) 2 -1/CC is as low as 196 mV, and it is still maintained at 210 mV after a long-term chronopotentiometry (CP) test at a constant current density of 10 mA cm -2 for 32 h, demonstrating superior activity and long-term durability. Density functional theory calculations further reveal that dilute Ti substitution produces extra active sites and promotes more optimal OH* adsorption to the surface of the electrocatalyst.

In this work, a double-layer nitrogen-doped microporous hollow carbon@MoS 2 /MoO 2 nanosphere (NCs@MoS 2 /MoO 2 ) is prepared via a facile method utilizing Mo-mediated in situ growth on polyaniline-coated polystyrene spheres and carbonization process. Because of its unique structure, the as-obtained NCs@MoS 2 /MoO 2 exhibits a high specific capacitance (569 F g -1 at 1 A g -1 ) and excellent rate performance (54.8% capacitance retention) from 1 A g -1 (569 F g -1 ) to 20 A g -1 (312 F g -1 ) when directly used as a supercapacitor electrode. In a two-electrode system, it exhibits 81% capacitance retention and 91.4% Coulombic efficiency even after 5000 cycles at 5 A g -1 . Therefore, the prepared NCs@MoS 2 /MoO 2 shows to be an outstanding material for supercapacitor electrodes.