While dye-sensitized metal oxides are good candidates as H 2 evolution photocatalysts for solar-driven Z-scheme water splitting, their solar-to-hydrogen (STH) energy conversion efficiencies remain low because of uncontrolled charge recombination reactions. Here, we show that modification of Ru dye–sensitized, Pt-intercalated HCa 2 Nb 3 O 10 nanosheets ( Ru /Pt/HCa 2 Nb 3 O 10 ) with both amorphous Al 2 O 3 and poly(styrenesulfonate) (PSS) improves the STH efficiency of Z-scheme overall water splitting by a factor of ~100, when the nanosheets are used in combination with a WO 3 -based O 2 evolution photocatalyst and an I 3 − /I − redox mediator, relative to an analogous system that uses unmodified Ru /Pt/HCa 2 Nb 3 O 10 . By using the optimized photocatalyst, PSS/ Ru /Al 2 O 3 /Pt/HCa 2 Nb 3 O 10 , a maximum STH of 0.12% and an apparent quantum yield of 4.1% at 420 nm were obtained, by far the highest among dye-sensitized water splitting systems and comparable to conventional semiconductor-based suspended particulate photocatalyst systems.

MFI-type zeolites containing Ce species were prepared by a mechanochemically assisted two-step method, where first an amorphous Si–Ce–O composite was produced via a mechanochemical reaction of SiO2 and CeO2 and then transformed into an MFI-type zeolite under hydrothermal conditions. The Ce species in this sample were more highly dispersed than those in the two control materials: a Ce-containing MFI-type zeolite synthesized via the conventional one-pot hydrothermal approach and Ce species simply deposited on silicalite-1. The highly dispersed and small Ce species in the zeolite exhibited a unique catalytic performance for the oxidative conversion of methane after the impregnation of Pd species, and the combination of Pd and Ce species produced ethane even at reaction temperatures as low as 100–300 °C.

Metal−organic frameworks (MOFs) and coordination polymers (CPs) are potential candidates for high-performance photocatalysts because of their high tunability of electronic and structural properties. For example, MOFs and CPs having a high specific surface area (∼1000 m 2 g −1 ) have been applied as visible-light-driven photocatalysts for CO 2 reduction and water splitting. Herein, we show a unique CP possessing a metal−sulfur bond with Pb 2+ , an earth-abundant metal ion. Different from ordinary high-surface-area MOFs and CPs, this CP is nonporous and has just 0.7 m 2 g −1 surface area. Nevertheless, owing to its capability of absorbing visible light up to ∼500 nm, it efficiently photocatalyzes CO 2 reduction to formate (HCOO − ) under visiblelight irradiation with >99% selectivity and an apparent quantum yield of 2.6% at 400 nm, even without postmodification treatment such as cocatalyst loading. These values are the highest yet reported for a precious-metal-free single-component photocatalyst for the visible-light-driven reduction of CO 2 to HCOO − . This work may thus shed light on the great potential of nonporous CPs as building units of photocatalytic CO 2 conversion systems.

Controlling the location, state, and size of metal species in the metal cation-exchanged zeolites has been achieved using the framework Al distribution-controlled MFI-type zeolites.

AEI-type aluminosilicate zeolites with sheet-like morphology were successfully synthesized by the crystal growth inhibitors (CGI)-assisted method, where cetyltrimethylammonium bromide (CTAB) worked as a CGI. The obtained sheet-like AEI-type aluminosilicates showed...

The development of simple catalysts with high performance in the selective oxidation of methane to syngas at low temperature has attracted much attention. Here we report a nickel-based solid catalyst for the oxidation of methane, synthesised by a facile impregnation method. Highly dispersed ultra-small NiO particles of 1.6 nm in size are successfully formed on the MOR-type zeolite. The zeolite–supported nickel catalyst gives continuously 97–98% methane conversion, 91–92% of CO yield with a H2/CO ratio of 2.0, and high durability without serious carbon deposition onto the catalyst at 973 K. DFT calculations demonstrate the effect of NiO particle size on the C-H dissociation process of CH4. A decrease in the NiO particle size enhances the production of oxygen originating from the NiO nanoparticles, which contributes to the oxidation of methane under a reductive environment, effectively producing syngas.

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An iron‐based oxyhydroxide catalyst was developed for CO2 photoreduction into formic acid. As reported by Kazuhiko Maeda et al. in their Communication (e202204948), α‐iron(III) oxyhydroxide, which is an easily available soil mineral, was loaded onto an alumina support and then serves as a recyclable catalyst for the CO2 reduction reaction, showing 80–90 % selectivity and an apparent quantum yield of 4.3 % at 460 nm in the presence of a ruthenium(II) photosensitizer and an electron donor.