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1T-phase MoS2, a versatile two-dimensional transition-metal dichalcogenide, is typically synthesized using a one-pot hydrothermal method. However, inadequate control of the sulfurization, reduction, and crystallization processes in the autoclave leads to multilayer 1T-MoS2with high crystallinity, a small surface area, and few defects. Considering the aforementioned issues, a two-stage microreactor continuous hydrothermal flow synthesis (CHFS) system coupled with accurate control and rapid processing is used to prepare 1T-MoS2with abundant voids and a large surface area under 250 °C and 4.0–4.5 MPa. And density functional theory calculations reveal that nitrogenous species, acting as reductants and electron donors, lower the energy of 1T-MoS2by intercalation and surface adsorption, facilitating its swift synthesis within the presulfurization stage for 10 min and reduction stage for 24 min. The precisely controlled synthesis of porous 1T-MoS2, originating from prenucleation clusters, results in a large surface area of 201.5 m2/g, concentrated mesopores of 2–5 nm, and a pore volume of 0.58 cm3/g. Moreover, a significant transformation from the 1T to the 2H phase is prevented by rapid cooling downstream of the CHFS system.

Hydrogen-rich syngas production via diesel steam reforming (DSR) is of great interest because of the high H2/CO ratio and available external heat sources. In this study, catalysts (particle size (dp) = 3–5 mm) containing 10 wt % Ni were prepared through wet impregnation, and their performance was evaluated in a semipilot fixed-bed reactor (Φ = 42 mm). The catalyst was doped with La, which resulted in excellent catalytic performance under different operating conditions. The apparent activation energies of the catalysts for the model diesel (n-dodecane) steam reforming increased in the order Ni/Ce0.75La0.25O2−δ-γ-Al2O3(17 kJ/mol) < Ni/CeO2-γ-Al2O3(18 kJ/mol) < Ni/γ-Al2O3(27 kJ/mol). The model DSR over Ni/Ce0.75La0.25O2−δ-γ-Al2O3showed product stability and produced a high H2content (32 vol %). Fresh and spent catalysts were characterized by X-ray diffraction, N2adsorption–desorption isotherms, H2-temperature programmed reduction, inductively coupled plasma–mass spectrometry, X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and thermogravimetric analysis. The origin of the oxygen vacancies in the La-doped catalyst was elucidated using density functional theory calculations. The improvements in the activity and stability of the Ni/Ce0.75La0.25O2−δ-γ-Al2O3catalyst are attributed to (1) the enhancement in the oxygen release/storage capacity, (2) the stabilizing interaction between Ni and the surface La2O3phase, and (3) the small size (11 nm) and uniform distribution of Ni particles. Out of the tested catalysts, the spent Ni/Ce0.75La0.25O2−δ-γ-Al2O3catalyst showed the lowest coke deposition (5.8 mg/g-cat.) and the least severe Ni agglomeration after 10 h of testing because of its superior ionic mobility and oxygen storage capacity.

In(OH)3and InOOH were synthesized in a high-temperature continuous flow microreactor, which was much faster than the hydrothermal synthesis in a Teflon-lined autoclave. The phase transition interval of In(OH)3and InOOH is measured, and the effect of aging temperatures on equilibrium compositions was also theoretically calculated. A transformation from nanorods to nanocubes was observed when the aging temperatures increased. In(OH)3and InOOH were also synthesized with Sn dopant, which was proven to be beneficial for the transformation from In(OH)3to InOOH. The sensors based on cubic and hexagonal In2O3particles showed a fast response (4–5 s) and recovery speed (12–15 s) to acetone vapor at the optimum operating temperature of 290 °C. The sensor based on hexagonal In2O3showed a higher response than that based on cubic In2O3. This work provided a rapid, continuous, and high-temperature synthesis method of an In(OH)3, InOOH, and In2O3series.