The Seafloor Bio-Fuel Cell: Long-Term Power and Effects on Sedimentary Organic Matter

P.I. Reimers, Clare（俄勒冈州立大学）提案号：0242048提案标题：海底生物燃料电池：长期动力和对沉积有机物的影响项目摘要：这项研究的长期目标是全面开发海底生物燃料电池，使其作为多种形式的自主海洋仪器的动力源，其性能可能超过电池。放置在沉积物-水界面上的电化学装置可以利用沉积物中不断更新的自然化学资源作为燃料，溶解的海水氧作为氧化剂，长时间地收集低水平的电力。这项新技术的功能很像微生物燃料电池，利用了沉积物柱顶部几厘米处的电压梯度。通常将电子传送到底物（如FeOOH或S0）的细菌已被证明附着在埋藏的电极（阳极）上作为生物膜。这些微生物被怀疑通过阳极的直接还原来发电。在该提案中，PI概述了推进海底生物燃料电池更接近未来应用的工程和科学目标。具体目标是：(1)组装一个可在水面舰艇上部署的原型，该原型将导致既是传感器系泊的电源和底部重量的设备，(2)在海洋观测科学目标环境中对原型进行短期和长期性能测试，(3)评估连续与循环能量收集对测试期间性能的影响，以及(4)了解性能，微生物富集和有机物氧化之间的联系。决定这些能源最终效用的一个基本假设是，海底生物燃料电池可以利用缺氧沉积物中以有机物形式储存的几乎所有化学能。换句话说，海底生物燃料电池应该产生与化学海洋学家所说的氧气效应相同程度的有机物质再矿化。为了测试这个前提并实现这些目标，pi提议两次巡航到俄勒冈大陆架上的站点并上升。在每次巡航期间，将进行必要的测量，以量化背景沉积有机质再矿化过程和氧暴露历史。将部署4个生物燃料电池装置，经过3天测试后回收，然后在每个场址重新部署至多一年。沉淀物也将被收集起来用于双室生物燃料电池的实验室实验。

P.I. Reimers, Clare (OSU) Proposal #: 0242048Proposal Title: The Seafloor Bio-fuel Cell: Long-term Power and Effects on Sedimentary Organic MatterProject Summary The long-term goal of this research is to fully develop seafloor bio-fuel cells so they may outperform batteries as the power source for many forms of autonomous marine instrumentation. Electrochemical devices placed across the sediment-water interface can harvest low- levels of power for long periods of time by using natural, continually renewed, chemical resources in sediment as fuel and dissolved seawater oxygen as oxidant. This new technology functions much like a microbial fuel cell, taking advantage of the voltage gradient that occurs in the top few centimeters of the sediment column. Bacteria that ordinarily shuttle electrons to substrates such as FeOOH or S0 have been shown to attach to the buried electrode (anode) as a biofilm. These microorganisms are suspected to generate electricity by direct reduction of the anode. In this proposal the PI outlines engineering and science goals to advance the seafloor bio-fuel cell closer to future applications. Specifically the goals are to: (1) assemble a surface-ship-deployable prototype that will lead to devices that are both a power source and bottom weight for a sensor mooring, (2) run both short and long-term performance tests of prototypes in environments targeted for ocean observatory science, (3) evaluate the effects of continuous versus cyclic energy harvesting on performance during tests, and (4) understand linkages between performance, microbial enrichments and organic matter oxidation. An underlying assumption that will determine the ultimate utility of these power sources is that seafloor bio-fuel cells can tap nearly all the chemical energy stored as organic matter in anoxic sediments. In other words, seafloor bio-fuel cells should generate the same degree of organic matter remineralization as chemical oceanographers have termed the oxygen effect. To test this premise and accomplish these goals, the PIs propose two cruises to stations on the Oregon continental shelf and rise. During each cruise measurements necessary to quantify background sedimentary organic matter remineralization processes and oxygen-exposure history will be performed. Four bio-fuel cell devices will be deployed, recovered after 3-day tests then redeployed for up to one year at each site. Sediments will also be collected for laboratory experiments with two-chambered bio-fuel cells.