CAREER: Understanding the electrochemical properties of physical hole defects on functionalized B/C 2D materials for the 2e- reduction of O2 to H2O2

在化学系化学催化项目的资助下，加州州立大学富勒顿分校（CSUF）的Michael Groves博士将利用计算模型研究过氧化氢（H2O2）合成的替代机制。过氧化氢是一种环境友好型氧化剂，用于许多应用，包括水处理，纺织品和木浆漂白，电子工业和个人防护设备灭菌。目前，过氧化氢的工业生产以破坏环境的蒽醌法为主。一种特别有趣的方法是基于电化学和由碳和硼组成的二维（2D）纳米材料，通过这些结构中的物理空穴缺陷和官能团促进过氧化氢的合成。根据该奖项，格罗夫斯研究小组将模拟酸性官能团在相邻物理孔缺陷大小变化时产生过氧化氢的能力。物理系统将准备好验证从计算研究中得出的量子化学预测。本项目将作为本学期的几个教育实验之一整合到格罗夫斯博士的高级化学实验课程中，为学生提供基于课程的研究经验。这些新的教学实践，以及翻转课堂教学方法，将在这个高级实验室环境中进行评估，以确定它们对提高学生成功的影响。此外，本课程是科学推广计划的一部分，特别针对中小学生，通过CSUF的儿童2大学计划，借鉴格罗夫斯博士的研究项目进行实际演示。加州州立大学富勒顿分校的迈克尔·格罗夫斯博士正在研究H2O2合成的过程。特别关注的是功能化硼、碳和硼碳二维材料上的物理空穴缺陷的电化学性质的计算量化，用于双电子还原氧（O2）到过氧化氢（H2O2）。该项目有可能对二维材料和电化学产生更广泛的影响，通过测试假设，官能团（醇、羧酸、磺酸）的酸度可以通过石墨烯、硼苯和杂化材料中相邻的物理空穴缺陷进行修饰，这将影响O2到H2O2的电化学还原。新开发的大规范势动力学框架被用于这个项目，以确保密度泛函理论计算正确地描述电化学条件。首先，通过聚集聚类增强的进化算法，每次重新启动将在势能表面的一个独特区域进行搜索，用于确定这些碳/硼二维材料的形态作为物理空穴缺陷尺寸的函数。由于确定了每个物理孔尺寸和材料的全局最小候选值，因此将确定集合中两个官能团（醇、羧酸、磺酸）的所有组合的酸度。然后将每种材料的酸性最强、酸性最低和两种具有中间酸性的结构用于计算电化学将O2还原为H2O2的势垒。曼彻斯特大学的实验合作者正与格罗夫斯团队一起合成有希望的候选物质，以支持结构-活性关系的发展。最后，格罗夫斯博士将把这个项目纳入高级物理化学实验室，作为一个扩展的基于课程的本科生研究经验（CURE）。这个CURE，翻转课堂教学和服务学习活动，学生在项目过程中向1400名当地代表性不足的六年级学生展示互动实验，是该奖项正在开发的三个潜在的高影响力实践，旨在提高学生的成功。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With funding from the Chemical Catalysis Program of the Division of Chemistry, Dr. Michael Groves at California State University-Fullerton (CSUF) will be utilizing computational modeling to investigate alternative mechanisms for the synthesis of hydrogen peroxide (H2O2). Hydrogen peroxide is an environmentally friendly oxidant that is used in many applications including water treatment, textile and wood-pulp bleaching, the electronics industry, and personal protective equipment sterilization. Currently, industrial production of hydrogen peroxide is dominated by the environmentally destructive anthraquinone process. One approach of specific interest is based on using electrochemistry and two-dimensional (2D) nanomaterials composed of carbon and boron, whereby physical hole defects and functional groups in these structures promote hydrogen peroxide synthesis. Under this award, the Groves research team will model the ability of acidic functional groups to produce hydrogen peroxide when the size of adjacent physical hole defects is varied. Physical systems will be prepared to validate quantum chemical predictions derived from the computational studies. This project will be integrated into Dr. Groves’ senior chemistry laboratory course as one of several educational experiments performed over the semester, providing students a course-based research experience. These new teaching practices, as well as a flipped classroom instruction approach, will be assessed in this senior lab setting to determine their impact toward improved student success. Additionally, this course is a part of a scientific outreach program particularly directed at elementary/middle school students through CSUF’s Kids 2 College program, with hands-on demonstrations that borrow from Dr. Groves' research project. Dr. Michael Groves of California State University-Fullerton is investigating processes for H2O2 synthesis. A particular focus is the computational quantification of the electrochemical properties of physical hole defects on functionalized boron, carbon, and boron-carbon 2D materials for the two-electron reduction of oxygen (O2) to hydrogen peroxide (H2O2). This project has the potential for a much broader impact on 2D materials and electrochemistry by testing the hypothesis that the acidity of functional groups (alcohol, carboxylic acid, sulfonic acid) can be modified by adjacent physical hole defects in graphene, borophene and hybrid materials, and that this will influence the electrochemical reduction of O2 to H2O2. The newly developed Grand Canonical Potential Kinetics framework is being used for this project to ensure that the density functional theory calculations properly describe electrochemical conditions. First, an evolutionary algorithm, enhanced by agglomerative clustering, whereby each restart will search in a unique region of the potential energy surface, is being employed to determine the morphology of these carbon/boron 2D materials as a function of physical hole defect size. As global minimum candidates are identified for each physical hole size and material, the acidity of all combinations of two functional groups from the set (alcohol, carboxylic acid, sulfonic acid) will be determined. The most acidic, least acidic, and two structures with intermediate acidities for each material will then used to calculate the barriers for the electrochemical reduction of O2 to H2O2. Experimental collaborators at the University of Manchester are working alongside the Groves team to synthesize promising candidates to support the development of structure-activity relationships. Finally, Dr. Groves will be incorporating this project into the senior physical chemistry laboratory as an extended course-based undergraduate research experience (CURE). This CURE, flipped classroom instruction and a service-learning activity where students present interactive experiments to 1400 local underrepresented 6th grade students over the course of the project, are three potentially high-impact practices being developed under this award that are designed to improve student success.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.