Nature-inspired 1D-Oxide 1D-Chalcogenide Nanocomposites for Efficient Broad Spectrum Absorption and Photoelectrocatalysis

PI：Subramanian，Vaidyanathan提议编号：1337050机构：内华达大学雷诺标题：自然启发的1D-氧化物1D硫系化合物纳米复合材料用于高效的广谱吸收和光电催化PI试图验证这一假设：一种自然启发的树状？由一维氧化物纳米管-一维硫化物纳米线组成的体系结构将促进1)广谱光吸收，2)光生电荷分离、传输和利用的显著改善，以及3)增强的光催化过程。这项为期两年的活动的主要目标是：i)使用二氧化钛纳米管？cds/PbS纳米线作为代表性的光催化剂来验证这一假设；ii)使用a)2门课程中的内容，b)一本书，以及c)教育少数族裔学生。将实施一种实验方法来验证假设。这些方法将包括合成、表征和测试光催化剂在太阳能相关转换过程中的适用性。为了验证这一假设，将使用一套辅助工具，进一步深入了解纳米复合材料的光学、电子、光电化学和光催化性能。通过0D氧化物和1D氧化物分别与0D硫化物形成0D/0D氧化物-硫系化合物和1D/0D氧化物-硫系化合物复合材料来制备和测试各种二氧化钛/硫化镉纳米复合材料，将确保系统的基线比较和严格的假设检验。结构-性能关系的研究将涉及a)纳米线/纳米管的物理尺寸对促进广谱吸收的作用，b)使用标准和专门(光)电化学技术的电荷分离和传输，以及c)与0D等效物相比，一维氧化物-一维硫化物纳米复合材料的性能效率的提高。此外，还将进行实验，以了解这些纳米复合材料在一种鲜为人知的可持续方法--太阳能驱动的废物转化为燃料(H2)--中的适用性。上述寻求对一维纳米复合材料性质的基本了解的战略将解决目前光催化面临的主要挑战：使光催化剂最大限度地吸收可见光，并将其用于高效和可持续的太阳能利用。该项目将促进对太阳能发电的基础科学和应用科学方面的变革性影响。从基础科学的角度，它将有助于回答晶界减少是否有助于实现电荷通行的高速公路的形成，以及显著降低复合速率以促进氧化还原反应的问题。从应用科学的观点来看，改进的电荷分离可以直接和立即使许多与太阳能有关的应用受益，包括：i)太阳能电池，ii)用于生产燃料的光催化，以及iii)环境修复。能量转换(燃料电池)和能量存储(电池和电容器)等相关技术将受益于：i)能够为本文开发的合成策略提供模板；ii)从物理尺寸对电荷迁移率的作用的见解中吸取教训，并基于这些见解定制实验方案，以便进一步针对具体应用进行改进。研究工作将纳入教育和外展工作。

PI: Subramanian, VaidyanathanProposal Number: 1337050Institution: University of Nevada RenoTitle: Nature-inspired 1D-Oxide 1D-Chalcogenide Nanocomposites for Efficient Broad Spectrum Absorption and PhotoelectrocatalysisThe PI seeks to test the hypothesis: A nature-inspired ?tree-like? architecture consisting of 1D oxide nanotubes-1D chalcogenide nanowires will facilitate 1) broad spectrum light absorption, 2) a significant improvement in photogenerated charge separation, transport, and utilization, and 3) enhanced photocatalytic processes. The key objectives of this 2-year activity is to i) test this hypothesis using a TiO2 nanotube?CdS/PbS nanowire as a representative photocatalyst and ii) use the content in a) 2 courses, b) a book, and c) educating a minority student. An experimental approach to hypothesis validation will be implemented. The methods will involve synthesis, characterization, and testing the applicability of the photocatalysts in solar-related energy conversion processes.To test the hypothesis, a suite of complementary tools that provide further insights into optical, electronic, photoelectrochemical, and photocatalytic properties of the nanocomposites, will be employed. Preparing and testing various TiO2/CdS nanocomposites by combining 0D oxide and 1D oxide separately with 0D chalcogenide forming 0D/0D oxide-chalcogenide and 1D/0D oxide-chalcogenide composites will ensure a systematic baseline comparison and rigorous hypothesis testing. The examination of the structure- property relationships will involve evaluation of a) the role of the physical dimensions of the nanowire/nanotube towards facilitating broad spectrum absorption, b) charge separation and transport using standard and specialized (photo)electrochemical techniques, and c) improvement in the performance efficiencies of 1D oxide-1D chalcogenide nanocomposites compared to the performances of 0D equivalents. Further, experiments that provide insights into the applicability of these nanocomposites in a lesser-known sustainable approach - solar-driven waste-to-fuel production (H2 generation) - will be conducted. The aforementioned strategy to seek a fundamental understanding of the 1D nanocomposite properties, will address the principal challenges currently faced in photocatalysis: maximize visible light absorption by the photocatalyst and employ it for efficient and sustainable solar energy utilization.This project will facilitate a transformative impact on basic as well as applied science aspects of solar-driven energy generation. From a basic science standpoint, it will help answer questions on whether grain boundary reduction can help realize the formation of superhighways for charges to travel and significantly reduce recombination rates to promote redox reactions. From an applied science standpoint, improved charge separation can directly and immediately benefit a multitude of solar-related applications including: i) solar cells, ii) photocatalysis for fuel production, and iii) environmental remediation. Allied technologies such as energy conversion (fuel cells) and energy storage (batteries and capacitors) will benefit from i) being able to template the synthesis strategies developed herein and ii) draw from the insights on the role of physical dimensions on charge mobility and customize experimental protocols based on these insights for further application-specific improvements. The research efforts will be incorporate into the educational and outreach efforts.