剑桥大学首创“人造树叶”将阳光和二氧化碳转化为可再生燃料

剑桥大学的研究人员开发出了一种名为“人造树叶”的太阳能技术，它可以一步将二氧化碳和水转化为高能量密度的燃料，如乙醇和丙醇

与生物燃料和化石燃料不同，这些太阳能燃料不会造成碳排放，也不需要农业用地来生产，提供了一种可再生的净零碳解决方案

这种技术仍处于早期阶段，团队目前正在努力提高设备的效率，优化其吸收阳光和增加燃料产量的能力，并扩大设备规模以实现大量燃料生产

据油价网2023年8月4日报道，剑桥大学的研究人员已经开发出了一种太阳能技术，可以将二氧化碳和水转化为液体燃料，这种燃料可以作为即用型燃料直接添加到汽车发动机中。

剑桥大学研究人员在《自然能源》杂志上报道了这项新技术。

剑桥大学研究人员利用光合作用的力量，一步将二氧化碳、水和阳光转化为多碳燃料——乙醇和丙醇。这些燃料能量密度高，易于储存或运输。

与化石燃料不同，这些太阳能燃料的净碳排放量为零，完全可再生，而且与大多数生物乙醇不同，它们不会占用任何用于粮食生产的农业用地。

虽然这项技术仍处于实验室规模，但研究人员表示，他们的“人造树叶”是从化石燃料经济转型的重要一步。

生物乙醇被誉为汽油的清洁替代品，因为它是由植物而不是化石燃料制成的。如今上路的大多数汽车和卡车使用的汽油含有高达10%的乙醇(E10燃料)。美国是世界上最大的生物乙醇生产国：根据美国农业部公布的数据，美国种植的所有玉米产量中几乎有45%用于乙醇生产。

领导这项研究的欧文·赖斯纳（Erwin Reisner）教授指出：“像乙醇这样的生物燃料是一项有争议的技术，尤其是因为它们占用了可以用来种植粮食的农业用地。”

几年来，赖斯纳在尤瑟夫·哈米德化学系的研究小组一直在利用“人造树叶”开发受光合作用(植物将阳光转化为食物的过程)启发的可持续的零碳燃料。

到目前为止，这些“人造树叶”只能制造简单的化学物质，比如合成气，一种氢和一氧化碳的混合物，用于生产燃料、药品、塑料和化肥。但为了使这项技术更实用，它需要能够在一次单一的太阳能步骤中直接生产更复杂的化学物质。

现在，“人造树叶”可以直接生产清洁的乙醇和丙醇，而不需要中间步骤生产合成气。

研究人员开发了一种铜钯基催化剂。这种催化剂经过优化，可以让“人造树叶”产生更复杂的化学物质，特别是多碳醇类乙醇和正丙醇。这两种醇都是高能量密度的燃料，易于运输和储存。

其他科学家已经能够利用电力生产类似的化学物质，但这是第一次仅使用太阳能利用“人造树叶”生产如此复杂的化学品。

此研究论文的第一作者Motiar Rahaman博士提供了更多细节，“将阳光照射在‘人造树叶’上，并从二氧化碳和水中获得液体燃料是一种惊人的化学反应。通常，当你试图用‘人造树叶’装置将二氧化碳转化为另一种化学产品时，你几乎总是得到一氧化碳或合成气，但在这里，我们已经能够生产出一种实用的液体燃料，只需要利用太阳能。这是一个令人兴奋的进步，为我们的研究工作开辟了全新的途径”。

目前，这个设备只是一个概念验证，仅显示出适度的效率。剑桥大学研究人员正在努力优化光吸收器，使其能够更好地吸收阳光，并优化催化剂，使其能够将更多的阳光转化为燃料。进一步的工作还需要使该设备可扩展，以便生产大量的燃料。

“尽管还有很多工作要做，但我们已经展示了这些“人造树叶”的能力，”赖斯纳教授说，“重要的是，我们可以超越最简单的分子，在我们从化石燃料过渡的过程中，制造出直接有用的东西。”

这项研究得到了欧盟委员会玛丽斯克沃多夫斯卡-居里奖学金，剑桥信托基金，以及温顿可持续发展物理学项目的部分支持。Erwin Reisner是剑桥大学圣约翰学院研究员，Motiar Rahaman是剑桥大学圣约翰学院副研究员。

“人造树叶”技术是一个相当广泛的想法，利用太阳能来执行或驱动反应。从二氧化碳和水变成燃料似乎是个好主意。

但仍有很多问题需要解决。虽然让水和二氧化碳接近并不困难，但要找到合适的条件可能很难。比例、温度、污染、能量输入水平和其他相关因素参数都必须计算出来，然后制造出具有经济意义的“人造树叶”。

这很可能是可以做到的，也应该做到。但直到数亿年前，大自然才发现，氢与碳相连，可以储存能量，形成有用的分子。大多数重大科技进步都是在漫长时光中徐步而来。就碳氢化合物而言，至少到目前为止，大自然尚未找到更好的方式。

这表明这项技术可能是最好的想法之一，希望该研究前景光明。

李峻 译自 油价网

原文如下：

Pioneering Tech Turns Sunlight And CO2 Into Renewable Fuel

·     Researchers from the University of Cambridge have developed a solar-powered technology, called "artificial leaves," which can convert carbon dioxide and water into high energy density fuels such as ethanol and propanol in a single step.

·     Unlike biofuels and fossil fuels, these solar fuels do not contribute to carbon emissions and do not require agricultural land for their production, offering a renewable and net zero carbon solution.

·     The technology is still in its early stages, with the team currently working on enhancing the device's efficiency, optimizing its ability to absorb sunlight and increase fuel production, and scaling up the device to enable large volumes of fuel production.

University of Cambridge researchers have developed a solar-powered technology that converts carbon dioxide and water into liquid fuels that can be added directly to a car’s engine as drop-in fuel.

The researchers report on the new technology in Nature Energy.

The researchers harnessed the power of photosynthesis to convert CO2, water and sunlight into multicarbon fuels – ethanol and propanol – in a single step. These fuels have a high energy density and can be easily stored or transported.

Unlike fossil fuels, these solar fuels produce net zero carbon emissions and completely renewable, and unlike most bioethanol, they do not divert any agricultural land away from food production.

While the technology is still at laboratory scale, the researchers say their ‘artificial leaves’ are an important step in the transition away from a fossil fuel-based economy.

Bioethanol is touted as a cleaner alternative to petrol, since it is made from plants instead of fossil fuels. Most cars and trucks on the road today run on petrol containing up to 10% ethanol (E10 fuel). The United States is the world’s largest bioethanol producer: according to the U.S. Department of Agriculture, almost 45% of all corn grown in the US is used for ethanol production.

Professor Erwin Reisner, who led the research noted, “Biofuels like ethanol are a controversial technology, not least because they take up agricultural land that could be used to grow food instead.”

For several years, Reisner’s research group, based in the Yusuf Hamied Department of Chemistry, has been developing sustainable, zero-carbon fuels inspired by photosynthesis – the process by which plants convert sunlight into food – using artificial leaves.

To date, these artificial leaves have only been able to make simple chemicals, such as syngas, a mixture of hydrogen and carbon monoxide that is used to produce fuels, pharmaceuticals, plastics and fertilisers. But to make the technology more practical, it would need to be able to produce more complex chemicals directly in a single solar-powered step.

Now, the artificial leaf can directly produce clean ethanol and propanol without the need for the intermediary step of producing syngas.

The researchers developed a copper and palladium-based catalyst. The catalyst was optimized in a way that allowed the artificial leaf to produce more complex chemicals, specifically the multicarbon alcohols ethanol and n-propanol. Both alcohols are high energy density fuels that can be easily transported and stored.

Other scientists have been able to produce similar chemicals using electrical power, but this is the first time that such complex chemicals have been produced with an artificial leaf using only the energy from the Sun.

Dr Motiar Rahaman, the paper’s first author offered more details, “Shining sunlight on the artificial leaves and getting liquid fuel from carbon dioxide and water is an amazing bit of chemistry. Normally, when you try to convert CO2 into another chemical product using an artificial leaf device, you almost always get carbon monoxide or syngas, but here, we’ve been able to produce a practical liquid fuel just using the power of the Sun. It’s an exciting advance that opens up whole new avenues in our work.”

At present, the device is a proof of concept and shows only modest efficiency. The researchers are working to optimize the light absorbers so that they can better absorb sunlight and optimizing the catalyst so it can convert more sunlight into fuel. Further work will also be required to make the device scalable so that it can produce large volumes of fuel.

“Even though there’s still work to be done, we’ve shown what these artificial leaves are capable of doing,” said Reisner. “It’s important to show that we can go beyond the simplest molecules and make things that are directly useful as we transition away from fossil fuels.”

The research was supported in part by the European Commission Marie Sk?odowska -Curie Fellowship, the Cambridge Trust, and the Winton Program for the Physics of Sustainability. Erwin Reisner is a Fellow and Motiar Rahaman is a Research Associate of St John’s College, Cambridge.

The artificial leaf technology is quite a wide array of ideas using solar energy to perform or drive reactions. Going from carbon dioxide and water to a fuel seems like a great idea.

There is a lot to work out. While getting the water and CO2 in proximity isn’t difficult, getting the conditions right might be. Proportions, temperatures, contaminates, energy input levels and other incident parameters all have to be worked out and then manufacture leaves that make economic sense.

It very likely can be done and should be. But it was hundreds of millions of years ago nature figured out to store energy with hydrogen connected to carbon for useful molecules. Most of the big advancements have been set for a very long time. So far nature hasn’t turned up anything better.

That suggests this tech might be among the very best ideas. Lets hope development continues.