Bifunctional catalytic activity of anion-doped LaSrCoO for oxygen reduction and evolution reactions.

Here, we synthesized Co-based, anion-incorporated‍ ‌R‌u‌d‌d‌l‌e‌s-d‌e‌n‌-‌Popper perovskite electrocatalysts (LaSrCoO X ) and compared their catalytic performances in the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The ORR mechanism with the newly synthesized F-doped LaSrCoO catalyst was dominated by a four-electron process, and the number of electrons involved in the reaction increased compared with that for LaSrCoO. The OER activity of the hydride-doped LaSrCoO catalyst was the highest among the LaSrCoO system catalysts.

A Cocatalyst that Stabilizes a Hydride Intermediate during Photocatalytic Hydrogen Evolution over a Rhodium-Doped TiO Nanosheet.

The hydrogen evolution reaction using semiconductor photocatalysts has been significantly improved by cocatalyst loading. However, there are still many speculations regarding the actual role of the cocatalyst. Now a photocatalytic hydrogen evolution reaction pathway is reported on a cocatalyst site using TiO nanosheets doped with Rh at Ti sites as one-atom cocatalysts.

Application to Photocatalytic H2 Production of a Whole-Cell Reaction by Recombinant Escherichia coli Cells Expressing [FeFe]-Hydrogenase and Maturases Genes.

A photocatalytic H2 production system using an inorganic-bio hybrid photocatalyst could contribute to the efficient utilization of solar energy, but would require the development of a new approach for preparing a H2 -forming biocatalyst. In the present study, we constructed a recombinant strain of Escherichia coli expressing the genes encoding the [FeFe]-hydrogenase and relevant maturases from Clostridium acetobutylicum NBRC 13948 for use as a biocatalyst. We investigated the direct application of a whole-cell of the recombinant E.

Synthesis and Investigation of the Effect of Substitution on the Structure, Physical Properties, and Electrochemical Properties of Anthracenodifuran Derivatives.

A series of syn/anti mixtures of anthradifuran (ADF) and substituent compounds were systematically synthesized, and the effect of substitution at the 5,11-positions on the neutral and radical states of ADF was investigated. All compounds were measured and analyzed by absorption and fluorescence spectroscopy, cyclic voltammetry, electrochemical absorption spectroscopy, and DFT calculations. The absorption spectra of 5,11-substituent compounds in their neutral state were red-shifted.

Direct imaging of light emission centers in two-dimensional crystals and their luminescence and photocatalytic properties.

To fully understand the fundamental properties of light-energy-converting materials, it is important to determine the local atomic configuration of photofunctional centers. In this study, direct imaging of one- and two-Tb-atom emission centers in a two-dimensional Tb-doped Ca2Ta3O10 nanocrystal was carried. The emission centers were located at the Ca sites in the perovskite structure, and no concentration-based quenching was observed even when the emission centers were in close proximity to each other.

Modification effects of meso-hexakis(pentafluorophenyl) [26]hexaphyrin aggregates on the photocatalytic water splitting.

Water splitting activity of a GaN:ZnO photocatalyst was improved by meso-hexakis(pentafluorophenyl) [26]hexaphyrin (3). The hexaphyrin (3) assisted the water splitting reaction over the GaN:ZnO photocatalyst by using visible light energy around 600 nm.

Potential gradient and photocatalytic activity of an ultrathin p-n junction surface prepared with two-dimensional semiconducting nanocrystals.

The creation of p-n junction structure in photocatalysts is a smart approach to improve the photocatalytic activity, as p-n junctions can potentially act to suppress the recombination reaction. Understanding the surface conditions of the junction parts is one of the biggest challenges in the development of photocatalyst surface chemistry. Here, we show a relationship between the photocatalytic activity and potential gradient of the junction surface prepared from two-dimensional crystals of p-type NiO and n-type calcium niobate (CNO).

One-pot soft-templating method to synthesize crystalline mesoporous tantalum oxide and its photocatalytic activity for overall water splitting.

Crystalline mesoporous Ta2O5 has been successfully synthesized by a one-pot route using P-123 as the structure directing agent (SDA). A series of crystalline mesoporous Ta2O5 samples has been prepared by changing the calcination temperature. The surface area decreased and the pore size increased with the increasing calcination temperature, which were the results of crystallite growth.

Preparation of tantalum-based oxynitride nanosheets by exfoliation of a layered oxynitride, CsCa2Ta3O(10-x)N(y), and their photocatalytic activity.

Calcium tantalum oxynitride [Ca(2)Ta(3)O(9.7)N(0.2)](-) nanosheets were prepared by exfoliating a layered perovskite oxynitride (CsCa(2)Ta(3)O(9.

Synthesis and photocatalytic activity of rhodium-doped calcium niobate nanosheets for hydrogen production from a water/methanol system without cocatalyst loading.

Rhodium-doped calcium niobate nanosheets were synthesized by exfoliating layered KCa(2)Nb(3-x)Rh(x)O(10-δ) and exhibited high photocatalytic activity for H(2) production from a water/methanol system without cocatalyst loading. The maximum H(2) production rate of the nanosheets was 165 times larger than that of the parent Rh-doped layered oxide. The quantum efficiency at 300 nm was 65%.

Long-time charge separation in porphyrin/KTa(Zr)O3 as water splitting photocatalyst.

Artificial photosynthesis is one of the chemists' dreams and the separation of charges with long lives is fundamental for achieving artificial photosynthesis. In actual photosynthesis, Z-scheme excitation separates electronic charge with high efficiency using solar light. Here we report that photo-excitation in Cr-tetraphenylporphyrin chroride (Cr-TPPCl)/Zr doped KTaO(3) (KTa(Zr)O(3)) is analogous to the Z-scheme in photosynthesis, and that we achieve complete charge separation at room temperature.

Preparation of p-type CaFe2O4 photocathodes for producing hydrogen from water.

An (hk0)-oriented p-type CaFe2O4 (E(g): 1.9 eV) photocathode was prepared, and hydrogen and oxygen gases were produced from a photocell short-circuited by connecting the CaFe2O4 and n-type TiO2 electrodes under illumination without applying an external voltage. The open-circuited voltage was 0.

Charge-transfer mechanism in Pt/KTa(Zr)O(3) photocatalysts modified with porphyrinoids for water splitting.

The mechanism of photocatalytic splitting of H(2)O into H(2) and O(2) on Pt/KTa(Zr)O(3) modified with various porphyrinoids was investigated. The photocatalytic activity of KTaO(3) catalysts is improved by dye modification. Cyanocobalamin (vitamin B(12)) is the most effective for improving water-splitting activity, and the formation rates of H(2) and O(2) achieved values of 575 and 280 micromol g(cat.