Energy & Green Tech
How can we store solar energy for period when the sun doesn't shine? One solution is to convert it into hydrogen through water electrolysis. The idea is to use the electrical current produced by a solar panel to 'split' water ...
Aug 25, 2016
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3165
Energy & Green Tech
Solar energy is the cheapest and most accessible form of energy. Now, it promises to be more efficient than ever. Scientists from a Chinese solar technology company have developed a new type of solar cell that could be a ...
May 9, 2023
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108
Energy & Green Tech
As we move away from fossil fuels and shift to renewable energy to tackle climate change, the need for new ways to capture and store energy becomes increasingly important.
Dec 2, 2020
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Energy & Green Tech
The rows of blue solar panels that dot landscapes and rooftops are typically made out of crystalline silicon, the workhorse semiconductor found in virtually every electronic device.
May 23, 2019
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851
Electronics & Semiconductors
When it comes to the future of solar energy cells, say farewell to silicon, and hello to calcium titanium oxide—the compound mineral better known as perovskite.
Aug 3, 2020
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92
Energy & Green Tech
Sodium-ion batteries are a potential replacement for lithium batteries, but the anodes—positively charged electrodes—that work well for lithium-ion batteries don't provide the same level of performance for sodium-ion ...
Jan 12, 2021
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93
Machine learning & AI
A unique material, nickel oxide demonstrates the ability to learn things about its environment in a way that emulates the most basic learning abilities of animals, as my colleagues and I describe in a new paper.
Dec 22, 2021
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54
Energy & Green Tech
So far, solar cells based on polycrystalline cadmium selenide telluride (CdSeTe) have exhibited some crucial limitations, despite their low fabrication costs and advantageous qualities. Most notably, these solar cells exhibit ...
Energy & Green Tech
Crystalline silicon solar cells dominate the global photovoltaic market with module efficiencies of around 20-22%. However, the field of solar energy is wanting for innovative materials and approaches that yield even higher ...
Apr 13, 2023
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17
Engineering
A new approach to manufacturing perovskite solar cells has addressed previous problems and yielded devices with high efficiency and excellent stability, researchers at the National Renewable Energy Laboratory (NREL) report ...
Dec 23, 2022
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Crystallinity refers to the degree of structural order in a solid. In a crystal, the atoms or molecules are arranged in a regular, periodic manner. The degree of crystallinity has a big influence on hardness, density, transparency and diffusion. In a gas, the relative positions of the atoms or molecules are completely random. Amorphous materials, such as liquids and glasses, represent an intermediate case, having order over short distances (a few atomic or molecular spacings) but not over longer distances.
Many materials (such as glass-ceramics and some polymers), can be prepared in such a way as to produce a mixture of crystalline and amorphous regions. In such cases, crystallinity is usually specified as a percentage of the volume of the material that is crystalline. Even within materials that are completely crystalline, however, the degree of structural perfection can vary. For instance, most metallic alloys are crystalline, but they usually comprise many independent crystalline regions (grains or crystallites) in various orientations separated by grain boundaries; furthermore, they contain other defects (notably dislocations) that reduce the degree of structural perfection. The most highly perfect crystals are silicon boules produced for semiconductor electronics; these are large single crystals (so they have no grain boundaries), are nearly free of dislocations, and have precisely controlled concentrations of defect atoms.
Crystallinity can be measured using x-ray diffraction, but calorimetric techniques are also commonly used.
This text uses material from Wikipedia, licensed under CC BY-SA
