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Organic–inorganic hybrid coating has been applied on metallic corrosion protection effectively. Molybdenum disulfide (MoS2) nanosheets with graphene-like two-dimensional lamellar structure were an anticorrosion inorganic additive, rendering the organic coating better corrosion resistant. However, the aggregation and poor solubility are still current issues that should be addressed. Functionalization MoS2 nanosheets with surface modified by polydopamine (PDA) and silane coupling agent (KH560) were prepared in polyurethane (PU) composite coatings to obtain dense and intact multilayer network structure coatings for corrosion protection. KH560-PDA-MoS2/PU coating with crosslinked polymer network structure has a high impedance modulus, large contact angle, and strong hydrophobicity. The coating meets the national technical standards for salt spray testing and nitric acid (HNO3) titration testing, demonstrating excellent corrosion resistance. [ABSTRACT FROM AUTHOR]

Lithium rich-layered oxides have attracted widespread attention due to their high specific capacity and high energy density. However, severe lithium nickel mixing, poor lithium-ion migration rate, and surface side reactions greatly limit their development. Li1.2Mn0.54Ni0.13Co0.13O2 with different contents of Li1.5Al0.5Zr1.5(PO4)3 (LAZPO-LMNCO) is synthesized by wet chemistry and high-temperature solid-phase method. Fast lithium-ion conductor LAZPO coating effectively suppresses side reactions between the electrolyte and LMNCO surface and stabilizes the layered structure, which reduces lithium nickel mixing and increases the migration rate of lithium ions, thereby improving cycling stability. Lithium-ion diffusion coefficient of 3 wt% LAZPO-LMNCO electrode reaches 5.8 times that of pristine LMNCO. At 1C, the 3 wt% LAZPO-LMNCO electrode provides a capacity retention rate of 90.4% after 250 cycles, compared to 82.8% of LMNCO after 100 cycles. Even a high rate of 5C, it still maintains a capacity retention rate of 88.4% after 350 cycles. This work provides an effective method for reducing surface side reactions and improving electrochemical performance of Li1.2Mn0.54Ni0.13Co0.13O2. [ABSTRACT FROM AUTHOR]

Selenium as a cathode of lithium-selenium (Li-Se) batteries attracted much attention due to its higher conductivity than sulfur. In this work, we study perovskite Li0.5La0.5TiO3 (LLTO) as both an electrocatalyst and an absorbent of polyselenides and carbon nanotubes (CNTs) as a conductive agent to jointly prepare a composite material for Li-Se battery. The experimental results proved that the LLTO significantly accelerated the polyselenides conversion and its adsorption ability reduced the dissolution of polyselenides, and CNTs accelerated the conduction of electrons to the reaction interface. Due to the synergistic effect between LLTO and CNTs, Se/(LLTO+CNTs) electrode showed higher initial capacity and better cycle stability than Se/LLTO and Se/CNTs electrodes. At 0.5 C, the Se/(LLTO+CNTs) electrode showed 476.6 mAh g−1 of discharge capacity after 500 cycles, and the capacity retention rate was above 80%. Even at 2 C, it still reached 521.5 mAh g−1 of the initial capacity. This work provides an idea for restraining the shuttle effect in Li−Se batteries. [ABSTRACT FROM AUTHOR]

Mesoporous M-CeO2 (M = Ni, Co, Fe, Mn, and Cu) catalysts were prepared using the hard-template method and applied to investigate CO2 reverse water-gas shift (RWGS) reaction. The physicochemical properties were studied using H2-TPR, XRD, BET, CO2-TPD, and H2-TPD. Results show that the specific surface areas of the prepared Ni-CeO2, Co-CeO2, Fe-CeO2, Mn-CeO2, and Cu-CeO2 catalysts exceed 120 m2/g. CO2 RWGS reaction performances are affected by the d-orbital holes of transition metals. CO2 RWGS reaction catalytic activities are ranked as follows: Ni-CeO2 > Cu-CeO2 > Co-CeO2 > Fe-CeO2 ≈ Mn-CeO2. The Cu-CeO2, Fe-CeO2, and Mn-CeO2 catalysts maintain 100 % CO selectivity at the studied temperature. [ABSTRACT FROM AUTHOR]

Abstract: The catalytic properties of Ni, Co, and Co-Ni supported activated carbon (AC) catalysts for oxidation for the removal of carbon monoxide (CO) in H2-rich gas are investigated. Results show that Co x O y /AC and CoO–NiO/AC exhibit higher catalytic activity than NiO/AC and that CoO–NiO/AC gives high CO conversion of above 99.5% at a wide reaction temperature region of 413–463K. The addition of nickel oxide (NiO) can lead to enriched CoO species on the surface of CoO-NiO/AC. The higher catalytic activity and selectivity of CoO-NiO/AC compared with Co x O y /AC can be attributed to NiO playing an important role. [Copyright &y& Elsevier]

In order to clarify the role of oxygen vacancy (OV), five α-MnO 2 catalysts with abundant OVs are fabricated via a novel and facile redox-precipitation approach and employed to the toluene oxidation in air. The concentration of OVs in α-MnO 2 catalysts is regulated via the alkyl chain length of alcohols, and its correlation with catalytic performances is scientifically investigated based on various characterization technologies and density functional theory (DFT) calculation. The α-MnO 2 -C2 catalyst exhibits excellent catalytic activity (T 90  = 217 °C), stability, and water resistance for toluene oxidation in air. The OVs can induce the new bandgap states (BGS), which upshift the antibonding orbitals relative to the Fermi level (E f ), eventually favoring the formation of adsorbed active oxygen species. Furthermore, the OVs cause an increase in the amount of Mn 3+ , resulting in the elongated Mn-O bonds due to the strong Jahn-Teller effect of Mn 3+ . Therefore, the synergistic effects of OVs benefit toluene oxidation through L-H and MvK mechanisms over the prepared α-MnO 2 -Cx catalysts. This work reveals the important role of OVs in the promotion of toluene catalytic oxidation activity and also may provide new insights for the design of high-performance VOCs oxidation elimination catalyst., (Copyright © 2021 Elsevier Ltd. All rights reserved.)