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The selective catalytic reduction technology that uses CO as a reductant (CO-SCR) has great potential in addressing nitrogen oxides (NOx) pollution in industry. Herein, we reported the in situ growth of highly efficient CuMnO2 nanosheet catalysts on low-cost stainless steel mesh (SSM) by a hydrothermal method, which exhibited excellent CO-SCR performance. It has been demonstrated that the prepared CuMnO2 nanosheet catalysts with high crystallinity and an exposed (001) plane could realize 100% NO conversion and N2 selectivity at 310 °C, which is comparable to other reported Cu–Mn–O catalysts. Moreover, the reaction mechanism driven by the surface synergetic oxygen vacancy of Cu–□–Mn is also proposed for enhancement of the CO-SCR performance. The good mechanical strength, easy shape processability, and high temperature stability of the inexpensive SSM support, together with the good catalytic performance of the active CuMnO2 component, could make the CuMnO2/SSM monolithic catalyst more favorable for large-scale industry application in de-NOx. [ABSTRACT FROM AUTHOR]

Herein, we demonstrated the controllable synthesis of a centimeter-scale two-dimensional (2D) ZnO-doped Ga2O3 nanostructure layer by a liquid Ga–Zn alloy printing strategy at near room temperature. Different from the liquid Ga–In and Ga–In–Sn alloys, the surface oxidation behavior of a liquid Ga–Zn alloy follows an obvious competition and cooxidation characteristics instead of the dominant oxidation characteristic of Ga, which could be effectively used to precisely tailor the Zn content of 2D Ga2O3 films. With an increase of the nominal Zn content in the Ga–Zn alloy from 0 to 8 atom %, the real Zn content of 2D ZnO-doped Ga2O3 films gradually increases and finally reaches a maximum saturated value of 16–18 atom % at the eutectic component of 3.87 atom %. Correspondingly, the transmittance and band gap of 2D ZnO-doped Ga2O3 films could also be tuned by changes of the Zn content and crystallinity. The method proposed in this work provides a general route toward the doping synthesis of a diverse nonlayered 2D structure, which will shed light on the applications of various displays and deep-ultraviolet optoelectronic devices. [ABSTRACT FROM AUTHOR]

Developing efficient and low‐cost electrocatalysts toward oxygen evolution reaction (OER) has been one of the key research topics for overall water splitting due to the increasing demand for regenerated and clean energy. Herein, we report Ni2P@NiFe LDH hierarchical heterostructures in‐situ grown on nickel foam with good conductivity, strong substrate adhesion, special interface engineering and synergistic effects, which enables superior OER performance with a low overpotential of 204 mV at 10 mA cm−2 and a small Tafel slope of 33 mV dec−1 in 1 M KOH solution. This peculiar hierarchical hybrid electrode also possesses excellent electrochemical stability and long‐term durability at the current density of 50 mA cm−2 in an alkaline medium. More importantly, the proposed synthetic strategy of hierarchical heterostructures in this work will provide a general path to the preparation of various metal hydroxide catalysts for highly efficient OER. [ABSTRACT FROM AUTHOR]

This work reports a novel strategy to in situ grow TiO2 nanosheets on flexible Ti mesh as ideal support, and to modify CuO active components through multi‐step methods. The CuO/TiO2/Ti monolithic catalyst can realize the complete CO oxidation at 110 °C without the assistance of any noble metal and the outstanding long‐term stability can be also achieved. When using urea as deposition precipitant, CuO particle size will increase obviously with the reaction time longer than 6 h, which is adverse to the catalytic performance, showing the significant impact of CuO particle size on the CO oxidation capability. The deposition reaction carried out in different solutions is also investigated and the results show that CuO/TiO2/Ti catalysts synthesized in acid and alkaline condition exhibit superior catalytic performance owing to the high content of Cu1+/0 and adsorbed oxygen species (Oα) on surface, large surface area, and excellent redox capacity compared with that in reductive solution. More importantly, the as‐synthesized CuO/TiO2/Ti monolithic catalysts show outstanding low‐temperature performance and excellent long‐term stability, indicating the overwhelming advantage of in situ grown catalysts. It is expected that the peculiar in situ growth technology is capable of extending to monolithic catalysts for multiple applications in the future. [ABSTRACT FROM AUTHOR]

The development of efficient monolithic catalysts and their fabrication methods for low‐temperature and long‐term stable CO oxidation always remains a challenge for both fundamental research and technological application. In this work, an innovative synthetic strategy to in‐situ integrate Co3O4/TiO2 monolithic catalysts on flexible Ti mesh substrate through multi‐step processes was demonstrated. The in‐situ grown catalysts show strong substrate adhesion, large surface areas and a complete CO conversion temperature of 105°C, which is superior or comparative to most noble metal catalysts. The in‐situ grown Co3O4/TiO2 catalysts on Ti mesh also exhibit excellent long‐term stability that is critically important for industrial application. It is expected that the in‐situ synthesis strategy of well‐defined Co3O4/TiO2 monolithic catalysts on flexible mesh substrate can be extended to the development of a variety of oxide‐based monolithic catalysts towards diverse catalysis applications. [ABSTRACT FROM AUTHOR]

The development of advanced catalyst integration strategy is of great importance and promising for long‐term and stable gas catalysis in environmental processing. However, conventional catalyst fabrication techniques including spray method and spin coating cannot overcome the key problems of catalyst peeling off from substrate and related severe performance degradation. In this work, an in situ integration strategy of monolithic Au/TiO2 catalysts on Ti mesh for efficient and stable low‐temperature CO oxidation is reported. Plasma electrolytic oxidation technology can create a porous TiO2 seeding layer with strong substrate adherence. Subsequent hydrothermal reaction, ion exchange, and calcination processes can induce the in situ nucleation of sodium titanate nanosheets and their follow‐up conversion to TiO2 nanosheets with huge surface area. The oxygen defects generated in anatase TiO2 nanosheet supports can not only provide sufficient anchoring sites for the deposition and attachment of gold nanoparticles (Au NPs) during deposition–precipitation process, but also absorb and activate oxygen species. Meanwhile, the strong interactions between Au NPs and TiO2 support make the catalysts more chemically active. As a result, the Au/TiO2 monolithic catalysts can eliminate CO completely at low temperature and exhibit considerably high stability, suggesting their potential in practical applications. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) transition‐metal dichalcogenides (TMDs) such as molybdenum disulfide (MoS2) have recently attracted extensive interest for building future optoelectronic devices. However, the limited light absorption, low photoresponsivity and slow response speed in visible range inhibit their further application. Here, we proposed a promising approach to realize the high‐performance photodetectors (PDs) by constructing 2D‐MoS2 flake/1D‐ZnO nanowire mixed‐dimensional heterostructures. The integration of 1D‐ZnO on p‐type or n‐type MoS2 to form the mixed‐dimensional 2D‐MoS2/1D‐ZnO heterostructure PDs not only broadens the light response range, but also improves the photoresponsivity and response time of 2D‐MoS2 flakes. Under the 365 nm light illumination, the photoresponsivity, external quantum efficiency and response time of p‐MoS2/n‐ZnO PDs are as high as 24.36 A/W, 8.28×103 % and 0.9 s, respectively. Under 532 nm light illumination, the photoresponsivity, external quantum efficiency and response time are estimated to be 0.35 A/W, 80.9 % and 140 ms, respectively. These properties are superior or comparable to the performance of other reported 2D‐MoS2 flake PDs. This work provides a possible strategy for the realization of high‐performance optoelectronic devices by the integration of 2D‐MoS2 and 1D‐ZnO to form mixed‐dimensional heterostructures. [ABSTRACT FROM AUTHOR]