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Metal oxides have garnered significant attention in the oxygen evolution reaction (OER), where a distorted MO 6 octahedral unit has a marked impact on their performance. This study introduces the distortion coefficient to quantify the MO 6 distortion composed of its volume and shape, and reports the effect of MO 6 distortion on the activity and stability in rutile metal oxides for the OER. This provides a fundamental understanding for designing effective MO 6 active units for the OER.

In this study, ruthenium-doped CoFe-based layered double hydroxides on Ni foam (CoFe-ZLDH/Ru@NF) were fabricated via an etching-precipitation strategy. The resultant CoFe-ZLDH/Ru@NF exhibited excellent activity, showing low overpotentials of 219.8 mV and 60.9 mV to reach the current density of 10 mA cm -2 for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. As a bifunctional electrocatalyst, it was assembled in an anion exchange membrane water electrolyser (AEMWE) unit, performing as an anode and cathode simultaneously, which only required a cell voltage of 2.33 V to accomplish the industrial level current density of 1 A cm -2 and operated steadily for over 12 h, making it promising for utilization in hydrogen production.

Evidence on the association between dietary nutrient-wide intake and cardiovascular disease (CVD) is inconclusive. Therefore, we systematically assessed the association between dietary intake of 29 nutrients and CVD risk using a nutrient-wide association study. Data were obtained from 7878 Chinese adults participating in the China Health and Nutrition Survey (CHNS) wave 2004-2015. We estimated the association of 29 nutrients with CVD risk. Significant findings were replicated in the National Health and Nutrition Examination Survey (NHANES). Four nutrients (selenium, vitamin A, carotenoids, and total protein) were significantly associated with CVD risk in the CHNS. The hazard ratio (HR) and 95% confidence interval (CI) for nutrient intake in the third tertile compared to the first tertile were 0.68 (0.51-0.90), 0.70 (0.54-0.91), 0.64 (0.50-0.83), and 0.54 (0.38-0.77), respectively. In the NHANES replication, selenium maintained a similar direction and strength of association, while the other nutrients were not replicated successfully. Our results provide support for a negative association between selenium intake and CVD risk, while the association of vitamin A, carotenoids and protein with CVD warrants further studies to confirm.

Given a desired property, locating relevant materials is always highly desired but very challenging in a range of areas, including heterogeneous catalysis. Obviously, object-oriented design/screening is an ideal solution to this problem. Herein, we develop an inverse catalyst design workflow in Python (CATIDPy) that utilizes a genetic-algorithm-based global optimization method to guide on-the-fly density functional theory calculations, successfully realizing the highly accelerated location of active single-atom alloy (SAA) catalysts for the hydrogen evolution reaction (HER). 70 binary and 752 ternary SAA candidate catalysts are identified for the HER. Furthermore, via considering the segregation stability and cost of materials, we extracted 6 binary and 142 ternary SAA candidate catalysts that are recommended for experimental synthesis. Remarkably, guided by these theoretical identifications, homogeneously dispersed Ni-based bimetallic catalysts ( e.g. , NiMo, NiAl, Ni 3 Al, NiGa, and NiIn) were synthesized experimentally to test the reliability of the CATIDPy workflow, and they showed superior HER performance to bare Ni foam, indicating huge potential for use in real-world water electrolysis techniques. Perhaps more importantly, these results demonstrate the capacity of such a proposed approach for investigating unexplored chemical spaces to efficiently design promising catalysts without knowledge from the expert domain, which has far-reaching implications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Graphitic carbon nitride (g-C 3 N 4 ) has been identified as a promising material for photocatalytic hydrogen (H 2 ) production, but it shows a low activity. Herein, g-C 3 N 4 doped with a benzene ring (B-CN x ) was synthesized via a simple thermal polycondensation method, exhibits 5.4 times higher H 2 evolution rate than the pristine one, and achieves a high apparent quantum yield of 4.11% at 420 nm.

Commercial nickel nanoparticles (Ni NPs) were directly converted to efficient electrocatalysts for CO 2 reduction by urea-Ni solid powder pyrolysis, in which a Ni, N-co-doped graphite carbon shell wraps the Ni NPs in situ. 98.3% CO selectivity was realized with a current density of -20.2 mA cm -2 and an overpotential of 0.69 V.

It is of paramount importance to design and develop highly active and selective electrocatalysts for the CO2 reduction reaction. Herein, we obtained bismuth-based catalysts consisting of oxidized Bi2O2CO3 and metallic Bi featuring local shortened inter-layer Bi-Bi bonds from in situ reduction of bismuth oxyiodide (BiOI) microflowers, which showed over 90% formate faradaic efficiency in a wide negative potential region.

As one of the most promising light-harvesting materials, perovskites have drawn tremendous attention for their unique advantages, such as high efficiency, low cost and facile fabrication compared with other photovoltaic materials. Nevertheless, poor moisture tolerance of the perovskites greatly hampers the operation of such devices and hinders their commercialization. Herein, we demonstrate a facile dipping treatment using sulfur-oleylamine solution for surface atomic modulation of perovskite films. Oleylammonium polysulfides (OPs) would be self-assembled on the etched perovskite film as an ultrathin outer layer. This layer could passivate the surface chemical activity of the outer perovskite layers. Moreover, the hydrophobic OPs significantly enhance moisture stability of such devices. As a result, the obtained device without encapsulation retains more than 70% of its initial power conversion efficiency (PCE) after 14 days of exposure to a relative humidity of 40 ± 10%.

A hybrid light/ToF-SIMS system was used to analyze the dynamic chemical changes of perovskite CH3NH3PbI3 films under light illumination, in order to reveal the mechanism of light instability for perovskite materials. Real-time material degradation and quasi-reversible iodine migration were successfully observed.

The atomically controlled transition of nanohybrids and their effects on charge-carrier dynamics are highly desirable for fundamental studies in photocatalysis. Herein, for the first time, a method combining atomic monodispersity and single-atom alloy was used to prepare a new form of highly efficient silver-based cocatalysts (Ag 25 & Pt 1 Ag 24 ) on graphitic carbon nitride, representing a novel photocatalytic system for hydrogen evolution.

Water splitting is key to electrically-powered chemical fuel synthesis, but the slow kinetics of the oxygen evolution reaction (OER) hinder the wider promotion of such technology. Several first-row (3d) transition metal-based catalysts have been developed for the OER; however, these catalysts still require operating voltages that lie well above the fundamental thermodynamic potential. Here, we report high-valence metal molybdenum (Mo 6+ ) modulated 3d metal (oxy)hydroxides. The obtained multimetal FeCoMo based OER catalysts require an overpotential of 277 mV to reach the current density of 10 mA cm -2 on the glassy carbon electrode, and there was no evidence of degradation for about 40 hours of stability testing. The catalysts stay in their amorphous phases, potentially with atomically homogenous metal distribution. The in situ X-ray adsorption analysis unambiguously reveals the tuned electronic structures of the 3d metals owing to Mo 6+ , further demonstrating the modification effect of a high-valence metal for designing highly-efficient OER catalysts.

Porous oxygen-doped graphitic carbon nitride (g-C 3 N 4 ) with feeble nitrogen vacancies was fabricated through thermal polycondensation of melamine with an appropriate amount of polyvinylpyrrolidone. After optimization, the bandgap of g-C 3 N 4 can be narrowed by 0.2 eV and the specific surface area expanded, which contribute to increasing the utilization of solar energy. Consequently, the optimized g-C 3 N 4 exhibits impressive enhancement in photocatalytic hydrogen evolution performance, by nearly 5 times compared with the pristine one under the irradiation of visible light.

Developing efficient, stable and cost-effective electrocatalysts towards hydrogen production in alkaline environments is vital to improve energy efficiency for water splitting. In this work, we prepared Ni-Mn3O4 nanocomposites on Ni foam which exhibit an excellent hydrogen evolution reaction catalytic activity with a current density (j) of 10 mA cm(-2) at an overpotential (η) of 91 mV and show good stability in an alkaline medium.

Hierarchical CoMoO4 porous micro-flowers assembled from numerous ultrathin nanosheets were synthesized by a facile hydrothermal method. Benefiting from the high specific surface area and constituent nanosheets with an ultrathin thickness, the CoMoO4 micro-flowers exhibit substantially higher electrocatalytic activity and stability than the IrO2 benchmark for the oxygen evolution reaction.

A facile in situ vapour phase hydrothermal (VPH) surface doping approach has been developed for fabrication of high performance S-doped Co3O4 electrocatalysts with an unprecedentedly high surface S content (>47%). The demonstrated VPH doping approach could be useful for enrichment of surface active sites for other metal oxide electrocatalysts.

In this paper, a series of mesoporous anatase TiO2 crystals were prepared through a hydrothermal method. By using different carboxylic acids as solvents and additives, the morphology of the integral crystals as well as inner pores can be tuned by the chain length of the carboxylic acids. Further application of these anatase TiO2 crystals as the photoanode of DSCs resulted in an overall energy conversion efficiency of 7.55% because of their low electrical resistivity loss and improved light harvesting abilities.

In this work, we developed a general two-step method to prepare molybdenum carbide (Mo2C) nanoparticles stabilized by a carbon layer on reduced graphene oxide (RGO) sheets. The Mo2C-RGO hybrid showed excellent performance, which is attributed to the intimate interactions between Mo2C and graphene as well as the outer protection of the carbon layer.

The electrocatalytically inactive commercial WO3 can be transformed into an efficient counter electrode (CE) material for dye-sensitized solar cells (DSCs) via facile hydrogen treatment. The energy conversion efficiency of the DSCs with the hydrogen-treated WO3 CE was 5.43%, while the corresponding value for commercial WO3 with the stoichiometric surface was only 0.63%.

SnS nanosheets (NSs), SnS nanowires (NWs) and SnS2 nanosheets were synthesized and investigated as counter electrode (CE) catalysts in a I3(-)/I(-) based dye-sensitized solar cell (DSC) system for the first time. It is found that the SnS NS based DSCs show comparable power-conversion efficiency (E(ff) = 6.56%) to Pt (7.56%), while the E(ff) of SnS NW and SnS2 NS based DSCs are 5.00% and 5.14% respectively, indicating the excellent catalytic activity of SnS(x) for the reduction of triiodide to iodide.

As one of the most common chemical materials, titanium dioxide (TiO2) has been prepared and widely used for many years. Among all the applications, the biomedical applications of TiO2 have motivated strong interest and intensive experimental and theoretical studies, owing to its unique photocatalytic properties, excellent biocompatibility, high chemical stability, and low toxicity. Advances in nanoscale science suggest that some of the current problems of life science could be resolved or greatly improved through applying TiO2. This paper presents a critical review of recent advances in the biomedical applications of TiO2, which includes the photodynamic therapy for cancer treatment, drug delivery systems, cell imaging, biosensors for biological assay, and genetic engineering. The characterizations and applications of TiO2 nanoparticles, as well as nanocomposites and nanosystems of TiO2, which have been prepared by different modifications to improve the function of TiO2, are also offered in this review. Additionally, some perspectives on the challenges and new directions for future research in this emerging frontier are discussed.

Silicon (Si) doped anatase titanium dioxide (Ti(0.89)Si(0.11)O(2)) single crystals bound by high-index {201} facets and high-energy {001} facets were synthesized by a facile method. It was found that the Si-doping can widely extend the optical absorption edge into the visible-light region and highly reactive facets can enhance their photocatalytic activity, as revealed by the combination of experimental and computational studies.

Single-crystalline TiOF(2) crystals with cubical morphology were prepared via a facile solvothermal method and their transformation to anatase TiO(2) under different calcination conditions such as pure argon, moist argon and pure hydrogen sulfide (H(2)S) was explored by using XRD/Raman/UV-Vis/SEM/TEM/SAED. The non-metal sulfur doping was successfully fulfilled and the doped TiO(2) microcubes showed the best photocatalytic H(2) evolution property.

A new synthetic strategy was developed to prepare large-sized well-defined anatase TiO(2) nanosheets wholly dominated with thermodynamically unfavorable high-reactive {001} and {100} facets, which has a percentage of 98.7% and 1.3%, respectively. The as-prepared anatase TiO(2) nanosheets show a well-faceted morphology and have a large size in length (ca. 4.14 μm). The formation mechanism of the anatase TiO(2) nanosheets was also analyzed and investigated., (© The Royal Society of Chemistry 2011)

Uniform anatase TiO(2) particles exposed by {001} facets were successfully synthesized by using EDTA together with F as morphology controlling agents. The crystallographic structure as well as the growth mechanism of anatase TiO(2) particles was investigated systematically by XRD, SEM, TEM and XPS, respectively.

Anatase TiO(2) having different percentages of (001)/(101) surface demonstrated different behaviors for Li(+) ions insertion and much enhanced rate performance of Li-ion batteries.

Nanosized anatase TiO(2) single crystals with 18% {001} facets have a raised conduction band minimum by 0.1 eV, and exhibit photocatalytic activity both for generating *OH radicals and for splitting water into hydrogen that is markedly superior--by factors of 5.6 and 8.2, respectively--to reference ca. 3 microm anatase TiO(2) with 72% {001} facets.