2020年12月7日
Because of the many environmental problems caused by the use of fossil fuels, many scientists worldwide are focused on finding efficient alternatives.
尽管人们对氢燃料电池有很高的希望，但现实是，运输，存储和使用纯氢的成本巨大，这使得这一过程在当前技术方面具有挑战性。
In contrast, methanol (CH3o3）一种酒精，不需要冷藏，具有更高的能量密度，并且更容易和更安全。因此，过渡到基于甲醇的经济是一个更现实的目标。
However, producing electricity from methanol at room temperature requires a direct methanol fuel cell (DMFC); a device that, so far, offers subpar performance.
DMFCS中的主要问题之一是在甲醇交叉期间发生的不想要的“甲醇氧化”反应，也就是说，当它从阳极传递到阴极时。
This reaction results in the degradation of the platinum (Pt) catalyst that is essential for the cell's operation. Although certain strategies to mitigate this problem have been proposed, so far none has been good enough owing to cost or stability issues.
Fortunately, in a recent study published inACS Applied Materials & Interfaces, a team of scientists from Korea has come up with a creative and effective solution. They fabricated--through a relatively simple procedure--a catalyst made of Pt nanoparticles encapsulated within a carbon shell.
该壳形成了几乎无法穿透的碳网络，该网络具有由氮缺陷引起的小开口。尽管DMFC中的主要反应物之一可以通过这些“孔”到达PT催化剂，但甲醇分子太大而无法通过。
“碳壳充当分子筛，并对所需的反应物具有选择性，实际上可以到达催化剂位点。这可以防止PT核的不良反应，”explains Professor Oh Joong Kwon from Incheon National University, Korea, who led the study.
科学家进行了各种类型的实验，以表征制备的催化剂的整体结构和组成，并证明氧气可以通过碳壳和甲醇使其无法做到。
他们还找到了一种直接的方法，可以通过在热处理步骤中简单地改变温度来调整外壳中的缺陷次数。在随后的实验比较中，他们的新型炮弹催化剂的表现优于商业PT催化剂，并且提供了更高的稳定性。
Prof Kwon has been working on improving fuel cell catalysts for the past 10 years, motivated by the many ways in which this technology could find its way into our daily lives.“ DMFC的能量密度比锂离子电池更高，因此可以成为便携式设备（例如笔记本电脑和智能手机）的替代电源，”他说。
With the future of our planet on the line, switching to alternative fuels should be one of humanity's top goals, and this study is a remarkable step in the right direction.
Source:http://www.inu.ac.kr/mbshome/mbs/inuengl/index.html