Patchiya Phanthong

Highly-efficient steam reforming of methanol over copper modified molybdenum carbide

Cu doped molybdenum carbide (Cu–MoxCy) catalysts were prepared by carburization of Cu doped molybdenum oxide (Cu–MoO3) using a temperature-programmed reaction with a 20% CH4–H2 mixture at 700 °C. Phase transition of the prepared molybdenum carbide was found to be related to the doping amount of Cu: with the increase in the doping amount of Cu/Mo molar ratio of 1.6/98.4 to 10/90, the cubic α-MoC1−x phase increased in the catalyst, but with the continued increase of the doping amount to a Cu/Mo molar ratio of 15/85, the α-MoC1−x phase began to decrease, and when the Cu doping amount reached a Cu/Mo molar ratio of 25/75, the α-MoC1−x phase became very weak and mainly hexagonal β-Mo2C phase was found in the catalysts. TEM images indicated that carbon growth on the surface of Cu occurred during the carburization process in the case of high Cu doping. Steam reforming of methanol (SRM) over the Cu–MoxCy catalyst was investigated at a temperature range of 200–400 °C. It is found that Cu–MoxCy catalyst with Cu/Mo molar ratios in the range of 1.6/98.4–10/90 showed high catalytic activity as well as long-term stability. X-ray photoelectron spectroscopy analysis indicated the coexistence of CuI and CuII species on the surface of the molybdenum carbide. The existence of CuI could result in high activity for methanol conversion and high stability, which might result from the strong interaction between Cu and Mo2C support.

Embedded structure catalyst: a new perspective from noble metal supported on molybdenum carbide

An embedded structure of noble metal (Pt) in situ supported on molybdenum carbide was found for the first time, which hindered Pt sintering at high temperature, and promoted the interaction between Pt and molybdenum carbide. This structure exhibited an excellent and stable catalytic activity for water gas shift reaction at low temperature.

Preparing hydrophobic nanocellulose-silica film by a facile one-pot method

Hydrophobic nanocellulose-silica film was successfully prepared by a facile one-pot method using tetraethoxysilane (TEOS) and dodecyl triethoxylsilane (DTES). Morphological characterization of the hydrophobic nanocellulose-silica (NC-SiO2-DTES) film showed well self-assembled DTES modified silica spherical nanoparticles with the particle sizes in the range of 88-126nm over the nanocellulose film. The hydrophobicity of the NC-SiO2-DTES film was achieved owing to the improvement of roughness of the nanocellulose film by coating dodecyl- terminated silica nanoparticles. An increase in DTES loading amount and reaction time increased the hydrophobicity of the film, and the optimum condition for NC-SiO2-DTES film preparation was achieved at DTES/TEOS molar ratio of 2.0 for 8h reaction time. Besides, the NC-SiO2-DTES film performed superoleophilic property with octane and hexadecane contact angles of 0°. It also showed an excellent hydrophobic property over all pH values ranged from 1 to 14.

Amphiphobic nanocellulose-modified paper: fabrication and evaluation

Amphiphobic nanocellulose-modified paper with high durability is successfully fabricated using a facile two-step method. Firstly, nanocellulose-modified paper is prepared through dipping filter paper, i.e., glass microfiber (GM) filter paper and polytetrafluoroethylene (PTFE) filter paper in a dilute nanocellulose dispersed solution. Subsequently, the nanocellulose-coated paper is treated with trichloro(1H,1H,2H,2H-tridecafluoro-n-octyl)silane (FOTS) via chemical vapor deposition. The obtained paper is found to have superhydrophobicity and oleophobicity, repelling both polar and non-polar liquids, on which the drops of water and non-polar liquids with high molecular weight become marble shaped, and the contact angles of water and n-hexadecane reach 156° and 144°, respectively. Furthermore, such amphiphobic nanocellulose-modified papers exhibit excellent surface durability in several environments including at various temperatures, and in acid and alkaline solutions, salt solutions and seawater. In addition, such amphiphobic nanocellulose-modified papers show good repellant properties for several kinds of liquids from our daily life. With outstanding protection to a diverse range of liquids, the amphiphobic nanocellulose-modified paper can be applied in the fields of self-cleaning, anti-bacterial, and anti-corrosion materials.

Fabrication and evaluation of nanocellulose sponge for oil/water separation

Nanocellulose sponge was fabricated by a facile method: freeze-drying of nanocellulose aqueous suspension to sponge state, following by hydrophobic treatment with stearoyl chloride at 50 °C for 1 h. The obtained nanocellulose sponge showed superhydrophobicity (160° of water contact angle) and superoleophilicity with high protection from water but selective absorption of oil. Its absorption capacities for various kinds of oil and non-polar liquids were 25-55 times higher than its dry weight and exhibited excellent selectivity for absorbing of oil which spilled on the surface of water or underwater with high separation efficiency. This superhydrophobic nanocellulose sponge can be easily recovered by simple squeezing and reused at least 10 cycles with remained high separation efficiency. It is expected that such a biodegradable nanocellulose sponge can be applied to solve the oil spill accident and treat the oily wastewater from households and industries.