3D打印塑料和金属有机框架储氢罐

4G光元：来自美国国家标准技术研究院（NIST）和华盛顿特区美国大学的科学家们发现，3D打印的ABS塑料有可能集成能够在环境中储存和检测气体的物质。这个发现可能有助于应对温室气体和推进氢动力汽车的应用。

所涉及的物质称为金属有机骨架，简称MOF。MOFs材料本质上是一种材料能够吸引和储存气体的具体类型。目前，MOFs用于石油精炼过程。

最近，然而，一支由NIST和美国大学的科学家们公认的潜力在MOFs用于气体传感技术，主要是因为材料的能力，捕捉和过滤甲烷和二氧化碳等气体。

不过，该项目并没有释放到空气中简单捕捉材料温室气体分子，正如研究人员已经找到一种方法将MOF颗粒（据说有粉尘浓度时，散装）转化成实际的传感器结构。

这就是3D打印出现的地方。

科学家们意识到，如果他们能组合成3D打印材料的塑料材料，就有了在几乎任何形状或结构下制造MOF嵌入式传感器的潜力，使该技术适用于广泛的应用范围。

根据团队介绍，虽然一个简单的解决办法是房子的MOFs材料的理想材料由于其渗透性允许气体通过塑料，从而允许MOFs抓他们的目标气体，识别气体分子。

在进行测试时，研究人员发现，3D打印的塑料材料做的网格，为MOFs维持甚至分布在塑料即使它是由3D打印机过程融化的。当他们测试了3D打印的结构与储氢材料时，他们发现3D打印的对象有积极的结果。

3D打印abs-mof混合结构

事实上，当MOF塑料部分仅对塑料部分进行测试时，他们发现MOF混合物保留的氢量是塑料零件的50倍以上。

能够将这种特殊的气体储存在塑料零件中，在汽车工业中有很大的优势。作为传感器的科学家Zeeshan Ahmed解释说：“美国汽车业仍在寻找一种廉价、储存燃料的氢动力汽车轻量化途径和过程中。我们希望MOFs塑料可能会形成储氢箱的基础。”

艾哈迈德补充说：“我们的目标是找到一种储存方法，可以容纳4.5%的氢重量，我们现在有只有一点点，不到百分之一。”但是从材料的角度来看，我们不需要为了达到目标而进行戏剧性的改进。因为我们所看到的是只装了一半玻璃或塑料容器。”

研究人员已经发表的关于3D打印的MOF塑料研究，并准备发布一个二论文对课题着眼于如何有效地确定MOFs可以储存氢气和氮气分子。

本次研究也涉及如何确保3D打印的塑料结构的MOFs材料不含或降低湿度的侵蚀。研究人员说，他们将与其他NIST小组合作，继续研究这一课题。

第一次的研究，对3D打印的储氢材料abs-mof复合材料制成，在杂志上发表的“聚合物的先进技术。

3D printed gas-absorbing MOF-plastic sensors could help fuel hydrogen-powered cars

Oct 26, 2017 | By Tess

Scientists from the National Institute of Standards and Technology (NIST) and the American University in Washington, DC have found that 3D printed ABS plastic has the potential to integrate substances that can store and detect gases in the environment. The discovery could have applications in combatting greenhouses gases and in advancing hydrogen-powered vehicles.

The substance in question is called a metal-organic framework, or MOF for short. MOFs are essentially a type of material that can be adapted to attract and store specific types of gas. Currently, MOFs are used in petroleum refining processes.

Recently, however, a team of scientists from NIST and American University recognized the potential in MOFs to be used in gas sensing technology, largely because of the material’s ability to catch and filter such gases as methane and carbon dioxide.

Still, the project wasn’t quite as simple as releasing MOFs into the air to catch the greenhouse gas molecules, as the researchers had to find a way to transform the MOF particles (which reportedly have the consistency of dust when they are in bulk) into a practical sensor structure.

And that’s where 3D printing came in.

The scientists realized that if they could mix MOFs into 3D printable plastics that there was the potential to additively manufacture MOF-embedded sensors in almost any shape or structure, making the technology adaptable for a wide range of applications.

According to the team, plastic—though a simple solution—was the perfect material to house the MOFs because its permeability allows gases to pass through it, which would in turn allow the MOFs to catch the gas molecules they are designed to recognize.

After conducting tests, the researchers found that 3D printable plastic and MOFs did mesh well, as the MOFs maintained even distribution in the plastic even when it was melted by the 3D printer. When they tested a 3D printed structure with hydrogen-storing MOFs, they found the 3D printed object had positive results.

3D printed ABS-MOF mixed structures

In fact, when the MOF plastic part was tested against a plastic-only part, they found that the MOF mixture retained more than 50 times the amount of hydrogen than the plastic-only part.

Being able to store this particular gas in plastic parts could have big advantages in the auto industry. As NIST sensor scientist Zeeshan Ahmed explained: “The auto industry is still looking for an inexpensive, lightweight way to store fuel in hydrogen-powered car. We’re hoping that MOFs in plastic might form the basis of the fuel tank.”

'The goal is to find a storage method that can hold 4.5 percent hydrogen by weight, and we've got a bit less than one percent now,' Ahmed added. 'But from a materials perspective, we don't need to make that dramatic an improvement to reach the goal. So we see the glass—or the plastic—as half full already.'

The researchers have already published one study about the 3D printable MOF plastics, and are gearing up to publish a second paper on the topic which looks at how effectively certain MOFs can store hydrogen as well as nitrogen gas molecules.

This second study also reportedly addresses how to ensure the 3D printed plastic structures containing the MOFs do not erode or degrade in humidity. The researchers say they will continue working on the subject in collaboration with other NIST groups in the future.

The first research study, “Toward 3D printed hydrogen storage materials made with ABS-MOF composites,” was published in the journal Polymers for Advanced Technologies.