21ENGBIO Engineering biomineralized carbon-sulfur composites for clean energy technologies

在我们试图从基于化石燃料的经济向广泛使用脱碳能源过渡的过程中，电能储存是一个至关重要的问题。锂硫电池（li -硫电池）是为当今电子设备和电动汽车供电的商用锂离子电池的一个有前途的继任者，其理论容量高出一个数量级。然而，锂硫电池的商业化利用由于构成其阴极的硫材料的性质和充放电循环期间稳定性差的几个问题而被推迟。这些问题可以通过在导电碳材料和有机聚合物中嵌入硫来缓解。然而，这种碳硫（C-S）复合材料的生产目前是一个复杂的、能源密集型的化学过程。在这里，我们建议利用一些细菌的潜力，通过一个被称为生物矿化的过程，自然形成C-S复合材料。我们将与kujiense硫urvum细菌合作，这种细菌产生带有有机包膜的硫矿物。这种细菌在室温下生长，只使用二氧化碳、硫化氢和硝酸盐作为底物。因此，电池材料可以通过清洁和节能的生物过程生产，同时回收人类活动的三种有害废物。在这个项目中，我们的目标是更好地了解控制由硫urvum kujiense生产的C-S复合材料性能的生物和化学参数，并证明这些复合材料是高效的电池材料，并且可以大规模生产。如果成功，该项目将为未来的基因工程方法做好准备，以优化C-S复合材料的生产和Li-S电池应用的性能。通过这项研究，我们将为设计更可持续的电池材料做出贡献，用于储存可再生能源，从而参与实现脱碳，这是21世纪的紧迫挑战之一，也是实现全球气候目标的先决条件。

Electrical energy storage is a vital issue in our attempt to transition from an economy based on fossil fuels to the widespread use of decarbonized energy sources. Lithium-sulfur (Li-S) batteries are a promising successor to the commercial Li-ion batteries that are powering today's electronic devices and electric vehicles, holding a theoretical capacity an order of magnitude higher. However, the commercial utilization of Li-S batteries is delayed due to several issues related to the properties the sulfur materials composing their cathode and their poor stability during charge-discharge cycles. These problems can be mitigated by embedding sulfur within conductive carbon materials and organic polymers. However, the production of such carbon-sulfur (C-S) composites is currently a complex and energy-intensive chemical process. Here, we propose to harness the potential of some bacteria to naturally form C-S composites, through a process called biomineralization. We will work with the bacterium Sulfuricurvum kujiense, which produces sulfur minerals with organic envelopes. The bacteria grow at room temperature using only CO2, hydrogen sulfide and nitrate as substrates. Battery materials may thus be produced through a clean and energy-efficient biological process, while recycling three harmful waste products of human activity.In this project, we aim at gaining a better understanding of the biological and chemical parameters controlling the properties of the C-S composites produced by Sulfuricurvum kujiense, and demonstrate that these composites are efficient battery materials and that they can be produced at large scale. If successful, this project will prepare future approaches aimed at genetically engineering Sulfuricurvum kujiense to optimize C-S composite production and properties for Li-S battery applications. With this research, we will contribute to the design of more sustainable battery materials for the storage of energy from renewable sources, and thus participate in achieving decarbonization, one of the pressing challenges of the 21st century and a prerequisite to the achievement of our global climate goals.