Xinhua News Agency, Beijing, 65438+1October 18-Japanese scientists have designed a new type of catalyst using nano-materials, which can effectively catalyze the key step of artificial simulation of natural photosynthesis-using sunlight to decompose water, which is expected to improve the efficiency of hydrogen production and reduce the cost.
Low-cost production of hydrogen is the basis of realizing "hydrogen economy". One of the ideal schemes is to simulate the photoreaction stage of plant photosynthesis and decompose water with the help of sunlight. At present, the technology of artificial decomposition of water often needs to consume extra energy and other raw materials, or needs high-energy light, which can not use the visible light in the sun and needs high cost.
Recently, Osaka University in Japan issued a press release saying that its researchers combined ultra-thin black phosphorus and bismuth vanadate to design a new catalyst, which can effectively use sunlight to decompose water. Related papers were published in the new international edition of the German Journal of Applied Chemistry.
Black phosphorus is a single crystal of phosphorus. Ultra-thin black phosphorus has excellent semiconductor properties and is a hot spot in the research field of two-dimensional materials. It has strong light absorption and can absorb all wavelengths of light in the visible spectrum. Bismuth vanadate is a yellow inorganic compound, and its photocatalytic performance has attracted much attention in recent years.
The researchers said that the reduction of water by black phosphorus combined with the oxidation of water by bismuth vanadate can quickly transfer electrons under the action of visible light and decompose water into hydrogen and oxygen without consuming other raw materials. The visible region accounts for about half of the total energy of solar radiation, which can greatly improve the photocatalytic efficiency.
The energy used is different. The former uses carbon dioxide as the main carbon source and inorganic nitrogen-containing compounds as the nitrogen source to synthesize cell materials, and obtains the energy needed for growth by oxidizing external inorganic substances. The latter uses sunlight, water and carbon dioxide to synthesize organic matter on chloroplasts.
The life carriers of these two reactions are different, some of the former are low-level microorganisms; The latter is mainly high-grade green plants, and a small amount of low-grade microorganisms and bacteria can also be used.
These two reactions need different raw material conditions and products. The former uses carbon dioxide as the main carbon source and inorganic nitrogen-containing compounds as the nitrogen source to synthesize cell substances, while the latter is a biochemical process that uses photosynthetic pigments to convert carbon dioxide (or hydrogen sulfide) and water into organic substances and release oxygen (or hydrogen).