What are the applications of first principles in the new energy sector?

Good question. This concept might sound "sophisticated," but its underlying idea is very fundamental, and it's increasingly playing the role of a "behind-the-scenes hero" in the new energy sector.

I'll try to explain it in a way that an ordinary person can understand.

You can imagine "first-principles" as a method of playing LEGOs at the atomic level.

Traditional materials research often resembles "cooking." Researchers, based on experience and theory, throw various elements (ingredients) into a "pot," adjust the "heat" (temperature and pressure), and then see what "dish" (new material) they can "cook up" and how well it performs. This process can sometimes rely heavily on luck, requires a large number of repetitive experiments, and is both time-consuming and expensive.

First-principles calculations, on the other hand, are like having the ultimate instruction manual for LEGO bricks. It doesn't care what these bricks (atoms) have been assembled into before (existing materials); instead, it directly tells you:

• What each different-shaped brick (e.g., hydrogen atom, lithium atom, oxygen atom) is like on its own.
• What forces (chemical bonds) arise when they get close to each other.
• Based on the most fundamental physical rules (quantum mechanics), what stable structure will form when they are put together, and what properties that structure will have.

It starts entirely from the most basic, core rules, using computers to simulate and predict outcomes. So, it's not about "guessing" or "trying," but about "calculating."

So, in the new energy field, where exactly is this "atomic LEGO" method applied? Primarily in these areas:

1. Developing Better Batteries (e.g., Lithium-ion batteries, Sodium-ion batteries)

This is where first-principles are most widely applied and have yielded the most results. We all want our phone and electric vehicle batteries to charge faster, last longer, be safer, and have a longer lifespan.

• Searching for new electrode materials: The core of a battery lies in its positive and negative electrode materials. Researchers can use first-principles to calculate thousands, even tens of thousands, of previously unheard-of compounds. For example, by combining atoms A, B, and C in a certain structure, they can calculate:

  • How many lithium ions can this structure accommodate? (Determines battery capacity)
  • How fast do lithium ions move within it? (Determines charging speed)
  • Will this structure fall apart after repeated charging and discharging? (Determines battery lifespan)
  • Will it become unstable at higher temperatures, potentially leading to combustion? (Determines safety)

  Through this "virtual screening," scientists can quickly identify a few most promising candidate materials, which are then synthesized and verified in the lab. This is like using a super magnet to narrow down the search area for a needle in a haystack, greatly improving efficiency. Many new solid-state batteries and sodium-ion battery materials are designed this way.

2. Developing High-Efficiency Catalysts (e.g., for Hydrogen Energy)

Whether it's electrolyzing water to produce hydrogen or fuel cells generating electricity from hydrogen, "catalysts" are needed to make chemical reactions easier and more efficient. Previously, we often used precious metals like platinum, but it's too expensive for widespread adoption.

• Designing inexpensive catalysts: Using first-principles, we can observe how reactions occur at the atomic scale. For example, how a water molecule is "torn apart" on a catalyst surface to become hydrogen and oxygen.

  • Through calculations, we can determine which atom and which position on the material's surface has the highest "activity."
  • Then we can try to use inexpensive metals (like iron, nickel, copper) to mimic platinum's "active structure," or cleverly combine small amounts of precious metals with large amounts of inexpensive metals into alloys.

  This allows us to design new catalysts with performance close to platinum but at a significantly reduced cost, paving the way for the widespread adoption of hydrogen energy.

3. Improving Solar Cells

We want solar panels to convert more sunlight into electricity.

• Searching for new photovoltaic materials: The efficiency with which a material absorbs sunlight depends on its "band structure" (you can roughly understand this as its "appetite" for absorbing photons). First-principles can directly calculate the band structure of any material.
  • Researchers can use this to design new semiconductor materials that can absorb a wider range of sunlight, thereby increasing conversion efficiency. Perovskite solar cells, which have been very popular in recent years, heavily relied on first-principles calculations in their early research to understand their excellent optoelectronic properties.
  • At the same time, it can also calculate what impact "defects" in the material (e.g., a missing atom or an extra impurity) will have on performance, and guide how to avoid these harmful defects during the manufacturing process.

In summary:

The role of first-principles in the new energy sector is that of a "materials designer" and "virtual laboratory." It transforms materials research from a "trial-and-error" model into a "design first, then verify" model. While it cannot completely replace experiments, it can greatly guide direction, shorten research and development cycles, and reduce costs, making it a powerful engine driving the accelerated development of new energy technologies.