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

电能储存是我们试图从基于化石燃料的经济过渡到广泛使用脱碳能源的一个至关重要的问题。锂硫（Li-S）电池是为当今电子设备和电动汽车提供动力的商用锂离子电池的有前途的继任者，其理论容量高出一个数量级。然而，由于与构成其阴极的硫材料的性质及其在充电-放电循环期间的差的稳定性有关的若干问题，Li-S电池的商业利用被延迟。这些问题可以通过将硫嵌入导电碳材料和有机聚合物中来缓解。然而，这种碳-硫（C-S）复合材料的生产目前是一个复杂的和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，通过一个称为生物矿化的过程，自然形成C-S复合材料。我们将与细菌Sulfuricurvum kujiense一起工作，它可以产生带有有机包膜的硫矿物。细菌在室温下生长，仅使用CO2，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来生产，同时回收人类活动的三种有害废弃物。在本项目中，我们的目标是更好地了解控制硫化藻kujiense产生的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有效的电池材料，并且它们可以大规模生产。如果成功，该项目将准备未来的方法，旨在对Sulfuricurvum kujiense进行基因工程改造，以优化锂硫电池应用的C-S复合材料生产和性能。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，用于存储可再生能源的能量，从而参与实现脱碳，这是21世纪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.