Nitrided Ni/N-zeolites as efficient catalysts for the dry reforming of methane

Interzeolite Transformation of Borosilicate MWW to Metallosilicate BEA-Type Zeolites: Separated Kinetics of Structural Transformation and Metal Substitution

“…The Me 2p XPS spectra can be divided into the two spin–orbit doublets, i.e., Co 2p 1/2 (785.0–813.0 eV) and 2p 3/2 (775.0–784.0 eV), Ni 2p 1/2 (872.0–877.0 eV) and 2p 3/2 (850.0–854.0 eV), and Zn 2p 1/2 (1045.1–1045.8 eV) and 2p 3/2 (1022.0–1022.7 eV). Co and Ni 2p XPS spectra have the peaks of shake-up satellites centered at 786.8 and 804.6 eV for Co and 862.0 and 880.0 eV for Ni. − The Me 2p 3/2 XPS spectra can be deconvoluted into two or three peaks. While the peaks that appeared at the lowest binding energy for Co- and Zn-BEA can be ascribed to the oxidized Co and Zn species, − almost no NiO moiety was observed in Ni-BEA. − However, both the Me 2p 3/2 peaks that appeared at the highest and the second highest binding energies of Me-BEAs should come from the framework metal species, − and these two deconvoluted bands can be assigned to the isolated and intermediate framework metal species, respectively, because the higher binding energy indicates the stronger interaction with the framework oxygen atoms.…”

“…Co and Ni 2p XPS spectra have the peaks of shake-up satellites centered at 786.8 and 804.6 eV for Co and 862.0 and 880.0 eV for Ni. − The Me 2p 3/2 XPS spectra can be deconvoluted into two or three peaks. While the peaks that appeared at the lowest binding energy for Co- and Zn-BEA can be ascribed to the oxidized Co and Zn species, − almost no NiO moiety was observed in Ni-BEA. − However, both the Me 2p 3/2 peaks that appeared at the highest and the second highest binding energies of Me-BEAs should come from the framework metal species, − and these two deconvoluted bands can be assigned to the isolated and intermediate framework metal species, respectively, because the higher binding energy indicates the stronger interaction with the framework oxygen atoms. Additionally, the proportions of the two or three XPS peaks that appeared at high to low binding energy are comparable to those of their UV absorption bands at low to high wavelengths (Table S1).…”

Highly Sensitive and Selective Organic Gas Sensors Based on Nitrided ZSM-5 Zeolite

“…A commercial aluminosilicate NH 4 + form of ZSM-5 (SiO 2 /Al 2 O 3 = 23, CBV2314) used in the present study was purchased from Zeolyst. N-ZSM-5 was prepared via the previously reported procedures as mentioned in our report . About 1.0 g of the NH 4 -ZSM-5 sample was located in a tubular furnace and ramped to 500 °C with a heating rate of 2 °C min –1 under flowing N 2 (100 mL min –1 ) and were kept at the equal condition for 2 h. After the shift into a flowing pure NH 3 (100 mL min –1 ), the temperature was increased with a heating rate of 2 °C min –1 to 500, 700, or 900 °C to facilitate the N-ZSM-5 zeolites with diverse N amounts.…”

“…Nitridation is a promising method to substitute lattice O with framework N, which has less electronegativity than O . In our previous study, the most representative commercial zeolite, ZSM-5 (framework type MFI), showed excellent structural stability during nitridation at 900 °C . In addition, a nitrided ZSM-5 (N-ZSM-5) film was explored for selective NO 2 adsorption depending on the compensating cations or Si/Al ratio. , With respect to this, N-ZSM-5 harbors robust potential as an outstanding analyte channel material for NOx gas sensors when it is blended with a conductive polymer as an active layer.…”

Highly Active Ni–Ru Bimetallic Catalyst Integrated with MFI Zeolite-Loaded Cerium Zirconium Oxide for Dry Reforming of Methane

“…Decades of in-depth studies have shown that nickel is the most suitable DRM catalyst due to its low cost and high initial activity. − However, both CO 2 and CH 4 molecules are very stable because of their super high bond energies, particularly the activation of the C–O bonds of CO 2 and the C–H bonds of CH 4 , which is the reason such a DRM reaction is more likely to proceed at higher temperatures (>700 °C), and precisely that tends to lead to sintering or carbon deposition and results in the catalyst deactivation. , Many efforts have been made to combine nickel with other metals to form bimetal or polymetallic catalysts , or to use noble metal catalysts and focus on functional catalyst supports to solve these problems. − Among the many materials used for reforming reaction supports available in the literature, including γ-Al 2 O 3 , SiO 2 , MgO, ZrO 2 , CeO 2 , TiO 2 , zeolite (molecular sieve), MgAl 2 O 4 , AlN, and La 2 O 3 , zeolite has been proved to be common catalyst support with excellent performance. ,− Apart from the large specific surface area, high porosity, and outstanding thermal stability, zeolite also takes an important role in providing shape-selective catalysis and certain physical and chemical properties such as basicity, acidity, and renewability. , Compared with other zeolite catalysts, the ZSM-5 catalyst was observed to exhibit significant catalytic activity at relatively low temperatures for DRM reaction. , …”