Efficient overall water splitting in acid with anisotropic metal nanosheets

Water is the only available fossil-free source of hydrogen. Splitting water electrochemically is among the most used techniques, however, it accounts for only 4% of global hydrogen production. One of the reasons is the high cost and low performance of catalysts promoting the oxygen evolution reaction (OER). Here, we report a highly efficient catalyst in acid, that is, solid-solution Ru‒Ir nanosized-coral (RuIr-NC) consisting of 3 nm-thick sheets with only 6 at.% Ir. Among OER catalysts, RuIr-NC shows the highest intrinsic activity and stability. A home-made overall water splitting cell using RuIr-NC as both electrodes can reach 10 mA cm−2geo at 1.485 V for 120 h without noticeable degradation, which outperforms known cells. Operando spectroscopy and atomic-resolution electron microscopy indicate that the high-performance results from the ability of the preferentially exposed {0001} facets to resist the formation of dissolvable metal oxides and to transform ephemeral Ru into a long-lived catalyst.

A novel design of SiH/CeO2(111) van der Waals type-II heterojunction for water splitting

Searching economical low-dimensional materials to construct the high-efficient type-II heterojunction photocatalyst for splitting water into hydrogen is very strategic. In this study, using the first-principles calculations, we construct a novel...

Progress in Photocatalysis of g-C3N4 and its Modified Compounds

Recently, graphitic carbon nitride (g-C3N4), a polymeric semiconductorhas been widely used as a low-cost, stable, and metal-free visible-light-active photocatalyst in the sustainable utilization of solar energy, such as water splitting, organic photosynthesis, and environmental remediation, which has attracted world wide attention from energy and environmental relative fields. Base on analysis of structure and theoretical calculation, the reasons that g-C3N4 can be used as a non-metallic catalyst were discussed in this paper. Some group's research jobs that metal-supported g-C3N4, metal-supported g-C3N4/organnic semiconductor compound and heterogeneous junction adjust the semiconductor electronic band structure have been summarized. And the mechanism, effect factors, and research developments on the reaction of organic degradation by photocatalytic and splitting water for hydrogen revolution catalyzed by above-mentioned modified g-C3N4 were emphatically analyzed. Finally, the prospects for the development of highly efficient g-C3N4 based photocatalysts are also discussed.

Utilization of Hydrogen Gas through Water Electrolysis Process (Galvanized Steel Electrodes) as an Alternative Fuel

The issue of the fossil fuel energy crisis has always been an essential subject inIndonesia and globally. The increasing use of liquefied oil gas (LPG) makes fuel prices moreexpensive. Therefore some developing countries are racing to find breakthroughs in producingmuch stronger and cheaper renewable energy. This research was conducted to produce gasstoves with water-based materials using water electrolysis techniques. Water electrolysis occursby splitting water molecules into oxygen and hydrogen gas by transferring electrical current toelectrolytes (water solution and NaOH) through zinc electrodes, which are galvanized steelsbecause the electrodes are not rusty or react with water. The effect is hydrogen gas, which isthen placed in a gas portable to be used as additional fuel to power the gas stove.

EXCELLENT ELECTROCATALYSIS OF OXYGEN EVOLUTION USING Co(OH)x(WO4)y/MESOPOROUS CARBON NANOCOMPOSITES

Oxygen evolution reaction (OER) is of great importance in splitting water. However, the sluggish OER kinetics at the anode severely hinders the H2 evolution at the cathode which is a crucial procedure for energy storage. Herein, we report the synthesis of a new OER catalyst of Co(OH)x(WO[Formula: see text] via a one-step hydrothermal method, where the incorporation of WO[Formula: see text] as a condenser greatly enhanced the electrocatalytic activity of Co(OH)2 toward OER. Moreover, the introduction of mesoporous carbon (MC) further improves the electrocatalytic performance of Co(OH)x(WO[Formula: see text] by forming the nanocomposites of Co(OH)x(WO[Formula: see text]/MC. The synergism between Co(OH)2 and WO[Formula: see text] and the synergistic catalytic effect of Co(OH)x(WO[Formula: see text] and MC majorly contributed to the apparently enhanced electrocatalysis of Co(OH)x(WO[Formula: see text]/MC toward OER. This work provides an efficient strategy to improve the electrocatalytic activity of Co(OH)2 by introducing WO[Formula: see text] and forming nanocomposites between Co(OH)x(WO[Formula: see text] and MC for low-cost, convenient and highly efficient water oxidation.

Recent Developments of TiO2-Based Photocatalysis in the Hydrogen Evolution and Photodegradation: A Review

The growth of industrialization, which is forced to use non-renewable energy sources, leads to an increase in environmental pollution. Therefore, it is necessary not only to reduce the use of fossil fuels to meet energy needs but also to replace it with cleaner fuels. Production of hydrogen by splitting water is considered one of the most promising ways to use solar energy. TiO2 is an amphoteric oxide that occurs naturally in several modifications. This review summarizes recent advances of doped TiO2-based photocatalysts used in hydrogen production and the degradation of organic pollutants in water. An intense scientific and practical interest in these processes is aroused by the fact that they aim to solve global problems of energy conservation and ecology.

Fabrication CdS/Au/TiO2 sandwich nanofibers for enhanced photoelectrochemical water-splitting efficiency

The sandwich-structured CdS/Au/TiO2 nanofibers (NFs) act as a photoanode in the photoelectrochemical cell (PEC) for hydrogen generation by splitting water. The gold nanoparticles sandwiched between the TiO2 nanofibers and the CdS quantum dots (QDs) layers play an important role in enhancing the solar-to-chemical-energy conversion efficiency. The structure and morphology of the materials were characterized by using field-emission scanning electron microscopy (FE–SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The surface plasmon resonance (SPR) of the Au nanoparticles was investigated by using ultraviolet-visible (UV–Vis) diffuse reflectance spectroscopy. The PEC properties of the photoanode were measured on a three-electrode electrochemical analyzer. The obtained photoconversion efficiency of the CdS/Au/TiO2 NFs is 4.1% under simulated-sunlight illumination with a 150 W xenon lamp. Working photoelectrode stability was tested, and the mechanism of the enhanced PEC performance was discussed.