Advanced functional nanomaterials for photocatalysis

随着世界人口的增加、经济的扩张和工业社会的快速发展，对清洁能源的需求迅速增长，环境污染日益严重，成为人类目前在全球范围内面临的两个最严重的问题。太阳能光催化被认为是解决能源危机和环境污染的最有前途的技术之一，它可以直接收集和利用丰富的、可持续的和可再生的太阳能。在一种情况下，太阳能可以通过所谓的光催化太阳能水分解转化为化学能，从而产生氢，一种环保的燃料来源。在另一个有吸引力的场景中，可以探索太阳能光催化，利用太阳能光催化降解污染物，从而解决环境问题以及清洁水短缺。尽管有很高的希望，太阳能光催化的商业应用仍然很少。阳光下的低转换效率一直是主要障碍，这主要是由于有限的吸收光谱范围，高载流子复合和/或低效率的电荷分离。没有一种材料能真正克服所有这些缺点。为此，基于不同性质纳米材料的组合而成的高功能纳米复合材料（NCs）作为一种天然而优秀的解决方案出现了。其中一类例子是等离子体-半导体纳米杂化材料，它最近作为一个有前途的候选者脱颖而出，因为等离子体材料可以延长和加强光吸收，增强激子的产生和解离，从而提高光催化效率。尽管如此，到目前为止，几乎所有与等离子体相关的研究都集中在昂贵的金和银上，这就提出了有关经济成本和长期可持续性的新问题。实现高性能、低成本、可持续性的纳米杂化光催化剂是人们迫切需要的，但也是具有挑战性的。为此，利用我们的专业知识，我们提出了一个充满活力的创新研究计划，其目标是：1)通过合理合成和表征先进的、具有成本效益的纳米材料，并通过将不同的纳米成分组装成高功能的纳米材料，开发宽带、高效的光催化剂；ii)了解光催化的主要机制、复杂的反应路径和活性物质，以及控制这些NCs合成和光催化行为的关键因素。它将产生科学和技术（工业）影响，并有助于培养高素质人才的多学科培训。

With the increase of the world population, the expansion of economy and rapid development of industrial society, rapidly growing demand for clean energy and increasingly severe environmental pollution are becoming two of the most serious issues human kind presently faces on a global scale. Solar-enabled photocatalysis is considered to be one of the most promising technologies for tackling both the energy crisis and environmental pollution by directly harvesting and utilizing the abundant, sustainable and renewable solar energy. In one case, the solar energy can be converted to chemical energy by the so-called photocatalytic solar water splitting, leading to the generation of hydrogen, an environmental-friendly fuel source. In another attractive scenario, solar-enabled photocatalysis can be explored to use the solar energy to photocatalytically degrade contaminants and thus address environmental problems as well as clean water shortage. Despite high promises, the commercial applications of solar-enabled photocatalysis remain scarce. Low conversion efficiency under sunlight has been a major obstacle and it is largely due to the limited absorption spectral range, high charge carrier recombination and/or low efficiency charge separation. No single material can indeed overcome all these shortcomings. To this end, highly functional nanocomposites (NCs), based on the combination of nanomaterials with different properties, appear as a natural and excellent solution. One type of such examples is plasmonic-semiconductor nanohybrids, which recently stand out as a promising candidate because plasmonic materials can extend and strengthen light absorption, and enhance exciton generation and dissociation, and thus enhance photocatalysis efficiency. Nonetheless, almost all of the plasmonic-related studies have so far focused on expensive Au and Ag, which raises new questions about economic cost and long-term sustainability. It is highly desired yet challenging to realize highly performing nanohybrid photocatalysts at low cost with sustainability. For this purpose, capitalizing on our expertise we propose a vigorous, innovative research program with objectives: i) developing broadband, high-efficiency photocatalysts by rationally synthesizing and characterizing advanced, cost-effective nanomaterials and by assembling different nanocomponents to highly functional NCs; and ii) understanding the dominant mechanism(s), complicated reaction paths and active species of photocatalysis as well as critical factors governing the synthesis and photocatalytic behavior of these NCs. It will have both scientific and technological (industrial) impact and contribute to the multidisciplinary training of highly qualified personnel.