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Hydrodesulfurization (HDS) is one of the most efficient methods to remove harmful sulfur from oil to produce clean hydrocarbons. Molybdenum sulfide (MoS2) has been used extensively for HDS for several decades, which can be further improved toward more effective catalysts due to its distinctive phase-engineering nature. Here, 1T-2H mixed-phase MoS2 nanoflowers with tunable defects have been synthesized and used in the HDS reaction. A facile solvothermal method involving water, ethanol, and glycerin has been developed for generating stable mixed 1T-2H MoS2 in which the vacancies of both S and Mo have been produced. Detailed characterizations based on transmission electron microscopy, X-ray photoelectron spectra, Raman, and electron paramagnetic resonance show that the 1T/2H ratio and vacancies of MoS2 have been effectively tuned by changing the composition of solvothermal solvent. Temperature-programmed reduction results show greatly affected H2 adsorption behavior of MoS2 by engineering of the phases and defects. In the HDS of dibenzothiophene, stable defect-rich mixed 1T-2H MoS2 with high activity and high hydrogenation selectivity was obtained via the accurately controlled solvothermal environment of water, ethanol, and glycerin. The used catalyst still maintains high performance, which is attributed to the retained mixed 1T-2H phases and the dual defects in the harsh reaction environment.

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A metal−organic framework (MOF), named SCNU-Z2, based on a new heterotopic tripodal nitrogen-containing ligand, has been constructed. Due to the replacement of one imidazole group in the reported ligand with one tetrazole group, the charge of the framework is changed from cationic to anionic but retains the same framework structure. The framework consists of tubular channels with a diameter of 1.5 nm and exhibits satisfactory stability in water with a pH range of 3−11. The anionic nature of the framework allows the effective adsorption of the cationic dyes MLB, CV, and RhB with capacities of 455.6, 847.4, and 751.8 mg/g, respectively. Among them, the adsorption capacities for SCNU-Z2 on CV and RhB rank as the highest when compared with other reported MOFs. In contrast, SCNU-Z2 exhibits an extremely low capacity for anionic dyes MO and AO, making it useful for the separation of anionic and cationic dyes based on a charge-dependent mode. Interestingly, SCNU-Z2 can be used to degrade an anionic dye, MB, within 30 min under darkness at room temperature. The apparent activation energy of the dye degradation reaction is calculated to be approximately 18.96 kJ•mol −1 , implying that the catalytic reaction of MB can be considered as a low-temperature thermocatalytic reaction in the dark/SCNU-Z2 system.

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