Solar energy photo-chemical conversion of solar energy utilization

In the natural world of our blue planet, the entire biological group can be roughly divided into three categories: The first category is the original ecological crops, and its representative biological groups are grass, wood, algae and other green plants; they have the same thing in common. Under the sunlight, it can synthesize carbon dioxide and water in nature into carbohydrates through its own chlorophyll, and release oxygen at the same time. The second category is herbivores that use grass, wood, and algae groups as food for survival, and rely on them to “consume” these original ecological crops to maintain their own survival. The third category is the higher carnivores that use the original ecological crops and herbivores as energy sources to maintain their own survival. In the food chain formed by the biological pyramid of nature, with the survival logic of “sacrifice others and survive oneself”, matter also obeys the second law of thermodynamics in the process of repeated cycles: its energy conversion always only moves in a constant positive direction. It flows spontaneously, and there is bound to be loss in the process of flow. Obviously, in the cyclical process of this food chain, each stage of the process also has a large amount of consumption, or it is accompanied by loss. For example, if an animal wants to maintain its own survival, it needs to continuously obtain food to supplement the energy it consumes; and to obtain food, it must pay more labor or exercise, and excrete most of the food into feces and return to nature. . The excreta of herbivores and carnivores and the corpses left behind after death are absorbed and used by the original ecological crops as a nutrient again through light-chemical conversion under the action of microorganisms, bacteria and enzymes, as well as sunlight and heat. , And get due energy compensation from the solar radiation energy; so as to maintain the endless and sustainable development of the natural ecological environment of the earth.

In the photo-chemical conversion of solar energy, there are generally four forms: in addition to the “photoelectric effect”-short-wavelength high-intensity solar radiation, which can excite electrons in certain semiconductor materials to get rid of the bondage of atoms, generating electron-hole pairs , The formation of photovoltaic electromotive force, that is, the “photoelectric effect” such as photovoltaic cells that we widely use today; and the “photosensitive reaction” that some special substances exist; there are also “photosynthetic reactions” and “photodissociation reactions” . And the “photochemical reaction”-biological synthesis, is the most common form of transformation in the biological world of the earth’s nature.

Solar energy photo-chemical conversion

The so-called “photodissociation reaction” means that in the solar light radiation, light of different wavelengths will have different chemical dissociation effects on different substances; that is to say, the light of certain wavelengths in the light radiation of solar energy After being absorbed by a specific atom, it will become an excited atom, which may lead to various chemical changes. For example: Scientists are investigating and studying where does the oxygen in the earth and space come from? When it was enriched to the source in the earth’s atmosphere, it was discovered that when the earth was still in the early barbaric era, without green plants participating in photosynthesis, CO2 in a vacuum encountered strong solar radiation. 5% of carbon dioxide molecules will be directly dissociated into a C molecule and an O2 molecule after being excited by a certain wavelength of light radiation in the sun; instead of what we usually think that carbon dioxide (CO2) can only be decomposed into a CO molecule And an O2 molecule. This major discovery reminds us that if we can directly photodissociate carbon dioxide into carbon molecules and oxygen through solar radiation, as long as we truly master the physical and chemical mechanism of the above-mentioned “photodissociation reaction”, we can find solar photodissociation of carbon dioxide. With the reaction conditions of molecules, we can make full use of the “inexhaustible and inexhaustible” solar radiation to remove greenhouse gases in the earth’s atmosphere to the greatest extent, so as to purify carbon pollution to the atmosphere. This scientific discovery and invention is of great epoch-making significance. Because it may be the ultimate solution to the greenhouse effect of the earth’s atmosphere.