Hierarchical H-form ZSM-5 (h-ZSM-5) was synthesized and successfully functionalized with imidazolium-based ionic liquids for solvent-free insertion of carbon dioxide to epoxides and synthesis of cyclic carbonate. Tetrapropyl ammonium hydroxide and polyurethane foam were used as soft and hard templates, respectively, to introduce mesoporosity in the structure. The synthesized hierarchical H-form ZSM-5 provided a large surface area for covalent attachment of imidazolium-based ionic liquids to produce h-ZSM-5-IL. The successful synthesis of the new catalyst was confirmed by X-ray diffraction, Fourier transform infrared spectroscopy, the Brunauer–Emmett–Teller method, and scanning electron microscopy and utilized for the insertion of carbon dioxide to epoxides and production of cyclic carbonate under solvent-free conditions. High conversion and selectivity for the synthesis of cyclic carbonate and recovery of the catalyst for five consecutive times without loss of catalytic activity are the advantages of this newly synthesized catalyst.

The Ti-based metal−organic framework (MOF) MIL-125-NH 2 is one of the promising materials for solar water splitting because it contains a sensitizer and a catalytic center in a single structure. MIL-125-NH 2 as many other MOFs has a microporous structure with pore diameters less than 2 nm. Compared with common MOFs, hierarchical mesoporous materials exhibit very large specific surface areas that facilitate diffusion of active species, accelerate subsequent surface reactions, and increase the bubble release rate by providing larger free spaces. Thus, the development of a facile method to create hierarchical porous MOFs with larger pore sizes remains a chemical challenge. Furthermore, MOF-type semiconducting materials usually have low activities in oxygen evolution reaction, and the presence of a suitable cocatalyst is needed to reduce the large O 2 overpotential. This study attempted to generate a hierarchical MIL-125-NH 2 MOF material with embedded RuO 2 nanoparticles as a highly efficient cocatalyst in a simple one-step process for use in efficient solar water oxidation. Different amounts of RuCl 3 •H 2 O precursor salt were used simultaneously for creating hierarchical porosity in MIL-125-NH 2 and for producing the assumed RuO 2 cocatalyst. For comparison, a hydrochloric acid treatment was applied to generate hierarchical porosity in the MOF in the absence of ruthenium. The samples were characterized using high-resolution transmission electron microscopy (HRTEM), Brunauer−Emmett−Teller adsorption, powder X-ray diffraction, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy. HRTEM gave evidence that in the ruthenium oxidecontaining MIL-125-NH 2 samples, tetragonal RuO 2 nanoparticles are present. The materials were applied as photoelectrodes, and photoelectrochemical (PEC) water oxidation performance under visible light illumination was studied. The PEC water oxidation performance of the MIL-125-NH 2 layer could be strikingly improved with a photocurrent density of about 10 times more than that of the pure MOF at 1.23 V versus reversible hydrogen electrode in artificial seawater, as a result of the hierarchical MOF structure and the presence of RuO 2 as a cocatalyst. Furthermore, density functional theory calculations were performed to shed light on the electronic properties and the role of the RuO 2 in the assumed hole transport.

Low‐cost carbon‐based perovskite solar cells (C‐PSCs) without a hole transport layer (HTL) and metal contact are highly promising for marketing. However, lower efficiency than conventional PSCs and instability during the penetration of moisture through the porous carbon electrode as well as the incoming of ultraviolet (UV) light from the glass side of the device remain challenges. Herein, a multifunctional triple‐layer system containing TiO2/SiO2/CeO2 porous nanomaterials is numerically simulated and experimentally used on the glass side of HTL‐free C‐PSCs. This strategy is designed to increase cell efficiency by enhancing the antireflective feature and long‐term stability via the UV light blocking and superhydrophobic properties introduced to the surface. Furthermore, this system is durable against environmental pollutants due to the photocatalytic self‐cleaning effect of TiO2. A superhydrophobic carbon back contact is also used to sandwich the perovskite active layer between two superhydrophobic surfaces and further the humidity resilience of the device. The device with polydimethylsiloxane (PDMS)–TiO2/SiO2/CeO2/glass/meso‐TiO2/MAPbI3/superhydrophobic‐carbon configuration shows an efficiency of 16.60% among the HTL‐free C‐PSCs and superior long‐term stability (maintaining 98.5% of the initial efficiency without encapsulation) against UV light and relative humidity of 90% at 50 °C.

A novel heterogeneous nanocatalyst was established by supporting molybdenum (VI) on Zr 6 nodes in the structure of the well-known UiO-66 metalorganic framework (MOF). The structure of the UiO-66 before and after Mo (VI) immobilization was confirmed with XRD, DR-FTIR and UV-vis spectroscopy, and the presence and amount of Mo (VI) was identified by X-ray photoelectron spectroscopy and inductively coupled plasma atomic emission spectroscopy. TEM imaging confirmed the absence of Mo clusters on the MOF surface, while SEM confirmed that the appearance of the MOF has not changed upon immobilizing the Mo (VI) catalyst. BET adsorption measurements were used to confirm the porosity of the catalyst. The catalytic activity of this heterogeneous catalyst was investigated in oxidation of sulfides with H 2 O 2 in acetonitrile and oxidative desulfurization of dibenzothiophene. Easy work up, convenient and steady reuse and high activity and selectivity are prominent properties of this new hybrid material.

A heterogeneous catalyst was synthesized by immobilizing Mo(CO) 3 in a UiO-66 metal-organic framework. The benzene ring of the organic linker in UiO-66 was modified via liquid-phase deposition of molybdenum hexacarbonyl, Mo(CO) 6 , as starting precursor to form the (arene)Mo(CO) 3 species inside the framework. The structure of this catalyst was characterized using X-ray diffraction, and chemical integrity was confirmed using Fourier transform infrared and diffuse reflectance UV-visible spectroscopic methods.The metal content was analysed with inductively coupled plasma. Field emission scanning electron microscopy was used to measure particle size and N 2 adsorption measurements to characterize the specific surface area. This catalytic system was efficiently applied for epoxidation of alkenes and oxidation of sulfides. The Mo-containing metal-organic framework was reused several times without any appreciable loss of its efficiency.