NSF Convergence Accelerator Track M: Water-responsive Materials for Evaporation Energy Harvesting

植物的许多重要生理功能(如种子传播和埋藏)依赖于水分响应材料，这些材料在相对湿度(RH)变化时机械变形。最近，生物WR材料已经证明了与所有已知的肌肉和执行器相比，能够产生显著更高的能量驱动。它们使蒸发能量收集引擎和发电机的发展成为可能，当放置在合适的空气-水蒸气界面时，这些发动机和发电机可以自动运行。理论和物理研究表明，这些设备具有高度的可扩展性，可以产生与当前太阳能和风电场相当的电力，同时缓解这些可再生能源经常遇到的间歇性问题。尽管有希望，但WR材料的发展及其在蒸发能量收集中的使用仍处于初级阶段，并面临着一系列广泛的挑战。这项研究的总体目标是在基于WR材料的新型蒸发能量收集技术上取得变革性的进展，并将该技术从实验室规模推向现实世界。这项研究为全球能源转型提出了一种创新的跨学科解决方案，提出了一种具有成本效益、无污染和完全可持续的方法，使用水文循环中蒸发阶段的生物启发模拟来为下一代能源收集设备提供动力。研究人员设想，拟议的融合研究将显著加快水资源回收材料和蒸发能量收集等新兴领域的增长。最终，这项研究将为社会建立开创性的方法，将无处不在的、未开发的自然蒸发能源用于驱动、能源转换和环境保护。拟议的扩大参与活动将为来自代表不足群体的学生提供资源、研究和培训机会，极大地有利于STEM教育，并有助于可持续设计的教育和劳动力发展。通过融合生物材料、化学、模拟/人工智能(AI)、工程、产品设计、技术经济能源分析、环境影响和生命周期分析、水文分析、制造/生产和公共政策的汇聚和跨学科方法，我们的目标是：(I)探索和开发新的可再生水材料；(Ii)利用可持续设计原则扩大可再生能源材料的制造；(Iii)执行蒸发能量收集装置的系统级原型；以及(4)评估技术经济可行性并制定营销战略。这项拟议的工作将加深我们对天然材料基本可再生水原理的理解，并为将纳米级可再生水材料设计成宏观结构提供一般指导。这些见解将指导基于生物的WR材料的设计，与现有的执行器相比，具有更高的能量/功率密度，为在广泛的工程应用中使用可持续的肌肉状执行器开辟了新的机会。此外，拟议的蒸发能量收集系统的实验室规模原型和建模将为利用WR材料驱动蒸发源机械设备的旋转运动提供新的战略。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Many important physiological functions of plants (e.g., seed dispersal and burial) rely on water-responsive (WR) materials that mechanically deform in response to changes in relative humidity (RH). Recently, biological WR materials have demonstrated the capability to generate significantly higher energy actuation compared to all known muscles and actuators. They have enabled the development of evaporation energy harvesting engines and generators that operate autonomously when placed at a suitable air-water vapor interface. Theoretical and physical studies suggest that these devices are highly scalable and could produce power comparable to current solar and wind farms, while mitigating the intermittency issue that is often experienced by these renewable energy sources. Despite their promise, the development of WR materials and their use in evaporation energy harvesting is still in its infancy and faces a broad array of challenges. The overarching goal of this research is to make transformative progress on a new evaporation energy harvesting technique based on WR materials and move the technique from lab-scale to the real world. The research proposes an innovative and transdisciplinary solution to the global energy transition, forwarding an approach that is cost-effective, non-polluting, and fully sustainable, using bio-inspired analogs of the evaporation phase in the hydrologic cycle to power the next generation of energy harvesting devices. The researchers envision that the proposed convergence research will significantly accelerate the growth of the emerging fields of WR materials and evaporation energy harvesting. Ultimately, this research will establish groundbreaking approaches for society to use the ubiquitous and untapped energy source of natural evaporation for actuation, energy conversion, and environmental protection. The proposed broadening participation activities will provide resources, research, and training opportunities to students from underrepresented groups, greatly benefiting STEM education and contribute to education and workforce development in sustainable design.Through convergent and interdisciplinary approaches that merge biomaterials, chemistry, simulation/artificial intelligence (AI), engineering, product design, techno-economic energy analysis, environmental impact and life-cycle analysis, hydrologic analysis, manufacturing/production, and public policy, we aim to: (i) explore and develop new WR materials; (ii) scale-up the WR material manufacturing using sustainable design principles; (iii) execute system-level prototypes of evaporation energy harvesting devices; and (iv) assess techno-economic feasibility and develop marketing strategies. The proposed work will enhance our understanding of the fundamental WR principles of natural materials, as well as provide general guidelines to engineer nanoscale WR materials into macroscale structures. These insights will guide the design of biologically-based WR materials with superior energy/power densities compared to existing actuators, opening up novel opportunities for using sustainable, muscle-like actuators in a wide array of engineering applications. Moreover, the proposed lab-scale prototyping and modeling of the evaporation energy harvesting systems will provide new strategies for utilizing WR materials to drive the rotary motion of mechanical devices sourced through evaporation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.