New strategies bring new trends to batteries!

[ Hot Focus on Chemical Machinery and Equipment Network ] Batteries are almost ubiquitous in our daily life
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In recent years, the development of various batteries has been quite rapid, such as lithium batteries, hydrogen fuel cells, solar cells, etc.
, more and more new material systems are maturing, silicon carbon anodes, composite separators, new lithium salts, graphene conductive agents And other new materials are also more industrialized, but they are undoubtedly closely related to environmental protection energy
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"Environmental protection" has become the most popular word nowadays
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The core of environmental protection is "new energy", and the core of new energy is the battery
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The development potential of energy storage batteries is huge, but due to cost, technology, policy and other reasons, it is still in the market introduction stage, which lags behind the growth of power batteries, and the current traditional manufacturing process and decentralized order development model of battery products are difficult to meet the high battery market.
Quality and consistency requirements
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Only by aiming at high-precision, high-stability, fully automated, intelligent, and green production line manufacturing methods can we adapt to the new market
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　　A new strategy to improve the stability of perovskite solar cells
 

　　Perovskite is a material with the same crystal structure as the mineral perovskite oxide
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Atoms of these elements are well suited to form molecules with other atoms that are semiconductor materials whose electrons can be excited by light energy and guided along wires to generate electricity
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Perovskite solar cells are solar cells that use this organometallic halide semiconductor as a light-absorbing material
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　　Perovskite-structured materials are new types of solar cell materials that have emerged in recent years, with high photoelectric conversion efficiency, simple fabrication process, and low production and material costs
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Its core photoelectric conversion material is cheap and can be prepared in solution, which is easy to prepare by roll-to-roll technology that does not require vacuum conditions, and is easier to produce than traditional silicon cells
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After more than ten years of development, perovskite solar cells have become a photovoltaic technology with great commercial potential.
At present, its photoelectric conversion efficiency has reached the level of commercial crystalline silicon cells, and the large-area preparation technology route is also becoming more and more mature
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However, perovskite solar cells are prone to direct sunlight and their performance will degrade over time, and their poor stability remains a major problem restricting their commercialization
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　　Yang Yang's group at UCLA, in collaboration with Rui Wang's group at Westlake University's School of Engineering, and Jin-Wook Lee's group at Sungkyunkwan University, conducted an in-depth exploration of the energy level mismatch caused by traditional surface treatment strategies.
Organic cations in surface treatment materials can achieve effective surface defect passivation, but neglected halide anions lead to changes in surface potential that adversely affect long-term stability
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The scientific research team designed a new surface treatment strategy for this.
They reduced the offset of the surface potential by introducing organic anions to replace halogen anions
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　　This scheme achieves high photoelectric conversion efficiency and is a long-term stable perovskite solar cell
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After 2000 hours of all-weather accelerated light test, the perovskite cell still maintains an original photoelectric conversion efficiency of over 87%
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In contrast, under the same conditions and for the same amount of time, the performance of the untreated solar cells dropped to 65%
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　　This research lays the groundwork for the commercialization and widespread adoption of perovskite solar cell technology
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As the current mainstream photovoltaic technology, crystalline silicon photovoltaic power generation efficiency is getting closer and closer to the limit
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And perovskite solar cells use low-cost, relatively easy processes to fabricate and deposit onto surfaces the potential for high power conversion efficiency with tunable band gaps, meaning their production requires 20 times less material than silicon cells and does not use rare earths Metals, the manufacturing process is much less energy-intensive than conventional solar cells
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With the continuous development and improvement of technology, perovskite solar cells show their great potential in the future photovoltaic field
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　　Provide a new perspective for energy catalytic conversion and fuel cell fields
 

　　The rapid development of modern industry has also brought about increasingly severe energy and environmental problems.
The application of sustainable energy has brought new opportunities to solve these two problems, and the development of efficient and cheap catalysts is crucial for energy conversion.
important
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Among them, water electrolysis devices, hydrogen fuel cells and metal-air batteries have attracted much attention
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　　However, the cathodic reactions involved in these devices, such as redox reactions, are relatively slow.
Although the use of precious metals as catalysts can effectively speed up these reaction processes to improve the working efficiency of the above devices, the high cost caused by them is a serious restriction.
The practical application of these devices, therefore, the development of low-cost non-precious metal catalysts with high activity and high stability is considered to be the key to promoting the industrial application of the above energy conversion devices
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　　Carbon-based single-atom catalysts are novel, low-cost and high-performance catalysts that play an important role in electrochemical energy conversion and catalysis
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Carbon-based transition metal single-atom catalysts (MNCs) have the advantages of high element utilization, strong intrinsic activity, cheapness and abundance relative to noble metals, and have shown broad application prospects in electrocatalytic oxygen reduction and other fields
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But today, MNC catalysts face the bottleneck problems of poor stability in alkaline and acidic environments, and low exposure ratio of single-atom active sites, which is mainly due to the conventional pyrolysis method for treating MNC catalyst carbons constructed from carbon-nitrogen precursors.
The pore structure in the substrate is generally dominated by micropores, which can easily lead to limited exposure of active sites and hindered in-depth diffusion of electrolyte, which affects mass transfer and catalytic efficiency
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　　Recently, in order to construct an oxygen reduction catalyst with excellent performance and outstanding stability, researchers from the Qingdao Institute of Bioenergy and Processes, Chinese Academy of Sciences, in the early stage, biomass-derived iron-nitrogen-carbon, metal framework polymer morphology and structure adjustment, and carbon-supported platinum-based catalysts.
Based on the preparation of alloy nanocatalyst materials, through clever design, a very simple and effective organic weak acid salt-assisted pyrolysis strategy was developed to simultaneously improve the final iron-nitrogen-carbon catalyst mesopore distribution and iron single-atom content
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This strategy can effectively realize the in-situ coating of the complex, and the activity of the catalyst can still maintain more than 90% after 90 hours of operation in an alkaline environment of 0.
67V , which is significantly better than the 10-hour recovery commonly reported in the literature.
There will be obvious attenuation phenomenon, and good application effect has also been achieved in zinc-air fuel cells
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　　In order to continue to improve the application range of transition metal single-atom catalysts and promote the catalytic efficiency of platinum-based materials for oxygen reduction, the research group further designed and developed a complex chloroplatinate using cationic surfactants, and used it in the polymer synthesis process.
In situ implantation into low cobalt zeolite imidazolate framework materials
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Combined with the optimized in-situ reduction and alloying treatment strategies, a transition metal cobalt single-atom carrier-supported Pt3Co and cobalt nanoparticle hybrid structure with Co-NC coating can be obtained
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　　This strategy can achieve a highly uniform dispersion of platinum in the polymer, and can effectively alleviate the rapid migration and aggregation growth caused by high temperature, providing a structural guarantee for prolonged stability in a strong corrosive environment
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This research work provides a new idea for the synthesis of new high-efficiency catalysts with carbon-coated platinum-based nanoparticle structure materials and platinum-based components and transition metal single-atom active components at the same time.
The research in the field provides a new angle, and also provides conditions for a substantial increase in battery life
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　　After the country promulgated a green and energy-saving-oriented industry development policy, carbon neutrality and carbon peaking have once again become the targets of sniping
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The important thing is that this "national policy" level policy has listed new energy vehicles and energy storage as emerging industries.
The country's development focus is completely clear, and some relevant favorable policies will be gradually introduced.
There is room for battery applications in the future application field.
It will get bigger and bigger , from wearable devices to aerospace high-tech, all of which will be equipped with batteries
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　　(Source: Science and Technology Daily, China Science News, CNKI)