基于单原子催化剂的光热催化转化：原理和应用

在以碳中和为目标的全球共识下，太阳能作为一种取之不竭用之不尽的绿色环保能源被认为是替代传统化石燃料最有潜力的方式。在各种太阳能转换技术中，光热催化不仅可以最大化利用太阳能，在光场和热场双重驱动力作用下，还可以显著提升化学反应速率，引起广泛的研究兴趣。以孤立的单个原子均匀分散在载体上形成的单原子催化剂具有100%原子利用率、优异的催化活性、热稳定性等优势。因此，将单原子催化剂应用于光热催化开始受到越来越多的关注。本综述介绍了光催化、热催化和光热催化的基本原理和特征，同时列举一些典型的例子。随后以不同载体作为分类标准，总结了单原子光热催化应用的前沿研究进展。最后，提出了该催化体系所面临的挑战和未来的发展方向。本文旨在全面了解单原子催化剂在太阳能驱动光热催化领域的研究现状并为未来发展提供可行的建议。

Photothermal Catalytic Conversion Based on Single Atom Catalysts: Fundamentals and Applications

To achieve the stated goal of carbon neutrality, solar energy is regarded as the most promising alternative to traditional fossil fuels as a sustainable and clean resource. The key prerequisite for improving the efficiency of solar conversion is to maximize solar energy utilization. As a promising technology, photothermal catalysis can harness full-spectrum sunlight to activate photocatalysis and thermocatalysis through hot carrier generation and local heating. These synergistic catalytic effects driven by both light and heat can overcome the challenges associated with the low catalytic efficiency of photocatalysis and high energy consumption of thermocatalysis as well as modulate the reaction pathways to achieve desirable activity and selectivity. To achieve outstanding catalytic performance, photothermal materials should meet the requirements for sufficient electron-hole separation, efficient solar thermal generation, and abundant exposed active sites. Common fabrication strategies are based on the integration of materials with photo-active and photothermal conversion capabilities that often suffer from buried active sites, high temperature-induced deactivation, and complicated synthetic procedures. Single-atom catalysts (SACs) with isolated single atoms uniformly dispersed on a solid surface are advantageous for 100% atomic utilization and excellent catalytic activity. Therefore, these materials have received increasing attention for a wide range of applications. Many SAC substrates are endowed with hot carrier generation and photothermal conversion abilities under illumination. The strong chemical interaction between metal atoms and supports or surface lattice reconstruction can also prevent catalyst sintering even in long-term high-temperature environments. These unique features make SACs highly suitable for photothermal catalytic processes. Therefore, it is important to summarize recent advances in this field and provide in-depth insights into SACs-based photothermal catalysis to accelerate solar conversion technology development. Herein, the fundamental mechanisms and characteristics of photocatalysis, thermocatalysis, and photothermal catalysis are introduced and three photothermal catalysis modes categorized by driving force (including photo-driven thermocatalysis, thermal-assisted photocatalysis, and photo-thermal co-catalysis) are described and compared along with representative examples. The photothermal properties of SACs supported by carbon, semiconductors, and plasmonic materials are reviewed and pioneering studies for different applications are discussed in detail. Finally, the challenges and future research directions are proposed. This review aims to give a comprehensive understanding of photothermal catalytic processes driven by solar energy based on SACs and provide accessible guidelines for future development to achieve carbon neutrality targets.