储能新形态：锥形与盘状碳结构为钠离子电池开辟新路径

As global demand for electric vehicles and renewable energy storage surges, so does the need for affordable and sustainable battery technologies. A new study led by researchers from the Department of Materials Science and NanoEngineering at Rice University, along with collaborators from Baylor University and the Indian Institute of Science Education and Research Thiruvananthapuram, has introduced an innovative solution that could impact electrochemical energy storage technologies. The research was recently published in the journal Advanced Functional Materials.
随着全球对电动汽车和可再生能源存储的需求激增，对经济实惠且可持续的电池技术的需求也在增长。由莱斯大学材料科学与纳米工程系研究人员牵头，联合贝勒大学和印度科学教育与研究学院特里凡得琅分校的合作者开展的一项新研究，提出了一种可能影响电化学储能技术的创新解决方案。该研究最近发表在期刊《Advanced Functional Materials》上。

Using an oil and gas industry's byproduct, the team worked with uniquely shaped carbon materials -- tiny cones and discs -- with a pure graphitic structure. These unusual forms produced via scalable pyrolysis of hydrocarbons could help address a long-standing challenge for anodes in battery research: how to store energy with elements like sodium and potassium, which are far cheaper and more widely available than lithium.
利用石油和天然气行业的副产品，该团队研究了具有纯石墨结构的独特形状碳材料——微型锥体和圆盘。这些通过碳氢化合物可扩展热解产生的特殊形态，可能有助于解决电池研究中阳极长期存在的挑战：如何用钠和钾等元素储存能量，这些元素比锂便宜得多且储量更丰富。

"For years, we've known that sodium and potassium are attractive alternatives to lithium," said corresponding author Pulickel Ajayan, the Benjamin M. and Mary Greenwood Anderson Professor of Engineering at Rice. "But the challenge has always been finding carbon-based anode materials that can store these larger ions efficiently."
"多年来，我们一直知道钠和钾是锂的有吸引力的替代品，"通讯作者、Rice大学Benjamin M. and Mary Greenwood Anderson工程学教授Pulickel Ajayan说。"但挑战始终在于找到能够高效存储这些较大离子的碳基阳极材料。"

Breaking the graphite barrier
突破石墨屏障

Traditional lithium-ion batteries rely on graphite as an anode material. However, the same graphite structure fails when it comes to sodium or potassium. Their atoms are simply too big and interactions too complex to slide in and out of graphite's tightly packed layers.
传统的锂离子电池依赖石墨作为负极材料。然而，同样的石墨结构在钠或钾上却行不通。它们的原子实在太大，相互作用过于复杂，无法自如地进出石墨紧密堆积的层间。

But by rethinking the shape of carbon at the microscopic level, the team found a workaround. The cone and disc structures offer curvature and spacing that welcome sodium and potassium ions without the need for chemical doping (the process of intentionally adding small amounts of specific atoms or molecules to change its properties) or other artificial modifications.
但通过重新思考碳在微观层面的结构，该团队找到了一种解决方案。锥形和盘形结构提供的曲率和间距能够容纳钠离子和钾离子，而无需进行化学掺杂（刻意添加少量特定原子或分子以改变其性质的过程）或其他人工修饰。

"We were surprised to see just how well these pure, curved graphitic structures performed," said first author Atin Pramanik, a postdoctoral associate in Ajayan's lab. "Even without heteroatoms, they allowed for reversible intercalation of sodium ions and did so with minimal structural stress."
“我们惊讶地发现这些纯净的弯曲石墨结构表现如此出色，”第一作者、Ajayan实验室博士后Atin Pramanik表示，“即使没有Het掺杂，它们也能实现钠离子的可逆插层，且结构应力极小。”

Durable, scalable and green
耐用、可扩展且环保

In lab tests, the carbon cones and discs stored about 230 milliamp-hours of charge per gram (mAh/g) using sodium ions, and they still held 151 mAh/g even after 2,000 fast charging cycles. They also worked well with potassium-ion batteries, but the performance wasn't quite as strong as with sodium.
在实验室测试中，碳锥和碳盘使用钠离子储存了约230毫安时/克（mAh/g）的电荷，即使在2000次快速充电循环后仍保持151 mAh/g。它们在钾离子电池中也表现良好，但性能不如钠离子电池那么强。

Advanced imaging techniques like cryogenic transmission electron microscopy and solid-state nuclear magnetic resonance confirmed that ions were entering and exiting the carbon structure as expected and that the material held its shape over thousands of charge-discharge cycles.
低温透射电子显微镜和固态核磁共振等先进成像技术证实，离子如预期般进出碳结构，且该材料在数千次充放电Mission中保持形状不变。

"This is one of the first clear demonstrations of sodium-ion intercalation in pure graphitic materials with such stability," Pramanik said. "It challenges the belief that pure graphite can't work with sodium."
"这是在纯石墨材料中钠离子插层具有如此稳定性的首批明确证明之一，"Pramanik说，"它挑战了纯石墨无法与钠结合的传统认知。"

The implications are wide ranging. Not only does this pave the way for more affordable sodium-ion batteries, but it also reduces reliance on lithium, which is becoming more expensive and geopolitically complicated to source. And because the cone/disc carbon can be synthesized from oil and gas industry byproducts, it presents a more sustainable route for battery anode production.
影响范围广泛。这不仅为更经济实惠的钠离子电池铺平了道路，还减少了对锂的依赖——锂的开采成本正变得越来越高，地缘政治因素也使其来源更加复杂。由于锥形/碟形碳可从石油和天然气工业副产品中合成，这为电池负极生产提供了一条更可持续的路径。

A turning point for battery design
电池设计的转折点

While most research in this area has focused on hard carbons or doped materials, the new study marks a pivot in strategy -- emphasizing morphology over chemical modification.
虽然该领域的大多数研究都集中在硬碳或掺杂材料上，但这项新研究标志着策略的转变——强调形态而非化学修饰。

"We believe this discovery opens up a new design space for battery anodes," Ajayan said. "Instead of changing the chemistry, we're changing the shape, and that's proving to be just as interesting."
“我们相信这一发现为电池阳极开辟了新的设计空间，”Ajayan表示，“我们并未改变化学Strategy，而是改变了形状，事实证明这同样引人注目。”

"We're not just developing a better battery material," Pramanik said. "We're offering a real pathway to energy storage that's cleaner, cheaper and more widely available to all."
"我们不仅仅是在开发一种更好的电池材料，"Pramanik说，"我们正在提供一条真正可行的储能途径，它更清洁、更便宜，也更能普及到每个人手中。"

This research was supported by funding from Omega Power and India's Department of Science and Technology.
本研究由Omega Power和印度科技部资助。