ISSN 1008-5548

CN 37-1316/TU

最新出版

缺陷型TiO2光催化纳米材料的制备和光催化应用研究进展

Research progress on preparation and photocatalytic application of defective TiO2 photocatalytic nanomaterials


李贞子, 王佩, 阮众望, 周卫

齐鲁工业大学(山东省科学院) 化学与化工学院, 山东 济南,250353

引用格式:

李贞子, 王佩, 阮众望, 等. 缺陷型TiO2光催化纳米材料的制备和光催化应用研究进展[J]. 中国粉体技术, 2026, 32(3): 1-17.

Citation:LI Zhenzi, WANG Pei, RUAN Zhongwang, et al. Research progress on preparation and photocatalytic application of defective TiO2 photocatalytic nanomaterials[J]. China Powder Science and Technology, 2026, 32(3): 1-17.

DOI:10.13732/j.issn.1008-5548.2026.03.005

收稿日期: 2025-07-05, 修回日期: 2025-11-17,上线日期: 2026-01-19。

基金项目: 国家自然科学基金项目,编号: 52172206; 山东省重点研发计划项目,编号: 2024TSGC0121; 齐鲁工业大学(山东省科学院)

科教融合人才项目,编号: 2024RCKY018。

第一作者:李贞子(1981—),女(朝鲜族),教授,博士,博士生导师,研究方向为纳米材料光催化。E-mail:zzli@qlu.edu.cn。

通信作者: 周卫(1980—),男,教授,博士,黑龙江省杰出青年项目获得者,博士生导师,研究方向为多孔纳米材料光催化、电催化。E-mail:wzhou@qlu.edu.cn。


摘要目的 实现缺陷型二氧化钛(TiO2)在污染物高效降解、太阳能驱动水解制氢、二氧化碳光催化还原制备燃料、以及温和条件下氮固定合成氨等一系列能源与环境关键应用中的规模化与实用化。【研究现状】 全面概括多种主流的缺陷构建策略;重点阐释不同类型缺陷态调控TiO2光催化性能的内在物理化学机制:缺陷在材料带隙中引入中间能级,有效收窄其表观带隙,从而将光响应范围从紫外区显著拓展至可见光乃至近红外区域;这些缺陷位点可作为高效的光生电子捕获中心,使得更多电荷能够参与表面催化反应;缺陷位点能够作为高活性的表面反应中心,显著促进H2O、CO2、N2等关键反应物分子的吸附与活化,有效降低其反应能垒。【结论与展望】未来的研究的首要任务是致力于开发更为简单、绿色、成本可控且易于规模化生产的合成技术,同时确保所引入的缺陷在长期运行中保持稳定;大力推动先进原位-工况表征技术与理论计算的深度融合;应积极拓展缺陷型TiO2的应用边界,将其独特的理化性质应用于能源存储、高灵敏度化学传感、生物医学等新兴前沿交叉领域。

关键词催化; 二氧化钛; 缺陷调控; 纳米材料


Abstract

Significance To systematically address the severe environmental degradation and energy scarcity stemming from rapid global industrialization and urbanization in the 21st century, the development of highly efficient, clean, and sustainable energy technologies has become an urgent imperative. This field of research focuses on employing advanced defect engineering strategies to achieve precise electronic and structural modulation of titanium dioxide (TiO2) photocatalytic nanomaterials. The primary goal is to overcome the inherent limitations of pristine TiO2: 1) its wide bandgap (about 3.2 eV), which confines light absorption mainly to the ultraviolet region (about 5% of the solar spectrum), 2) the rapid recombination (on the nanosecond timescale) of photogenerated electron-hole pairs, which leads to low quantum efficiency. The ultimate objective is to establish a solid material foundation and theoretical framework for the large-scale and practical application of defective TiO2 in critical energy and environmental technologies. These include the highly efficient degradation of pollutants, solar-driven hydrogen production via water splitting, photocatalytic reduction of carbon dioxide (CO2) to fuels, and nitrogen fixation to ammonia under mild conditions.Progress This review systematically summarizes the recent research progress and emerging trends in defective TiO2 photocatalytic nanomaterials. First, it provides a comprehensive overview of the mainstream strategies for introducing defects, including hydrogenation reduction, chemical reduction (e.g., using NaBH4), high-energy particle irradiation (e.g., plasma, electron beams), electrochemical reduction, and chemical oxidation methods. A comparative analysis of these methods is conducted, highlighting their respective advantages and limitations in terms of the types of defects introduced (e.g., oxygen vacancies, Ti3+ species, surface disordered layers), the uniformity of defect concentration and distribution, process controllability, energy consumption, cost, and potential for future scalable application. Second, the intrinsic physicochemical mechanisms by which defect states enhance the photocatalytic performance of TiO2 are elucidated: 1) Defects introduce mid-gap states within the material’s bandgap, effectively narrowing its apparent width and thereby significantly extending light absorption range from the UV into the visible and even near-infrared regions.2) These defect sites, particularly oxygen vacancies, act as efficient trapping centers for photogenerated electrons, markedly suppressing the recombination kinetics of electron-hole pairs, effectively prolonging charge carrier lifetimes, and consequently allowing more carriers to participate in surface catalytic reactions. 3) Simultaneously, defect sites serve as highly active surface centers, significantly promoting the adsorption and activation of key reactant molecules such as H2O, CO2, and N2, and effectively lowering their reaction energy barriers. Special emphasis isplaced on the evolution of the field, which has progressed from the initial introduction of single defects towards the design and construction of synergistic multi-defect systems. For instance, the combination of nitrogen doping with oxygen vacancies creates a notable synergistic effect.It optimizes the electronic band structure, generates complementary active sites, and significantly enhances visible-light-driven hydrogen evolution performance. Substantial experimental evidence demonstrates that defective TiO2, exemplified by the remarkable “black TiO2” with its broad-spectrum absorption, exhibits exceptional photocatalytic performance across several domains. It enables highly efficient degradation of organic dyes and pharmaceutical pollutants under visible light irradiation.The material achieves orders-of-magnitude enhancement in hydrogen production rates, even without noble metal co-catalysts (with optimal rates reaching 43 mmol/(g·h).It also demonstrates high selectivity for hydrocarbon fuels such as methane during CO2 photoreduction (e.g., CH4 production rates of 115 μmol/(g·h).Notably, defective TiO2successfully accomplishes photocatalytic conversion of N2 and H2O directly to NH3under ambient temperature and pressure.These advantages offer a sustainable and potentially revolutionary alternative to the traditional, energy-intensive Haber-Bosch process.

Conclusions and Prospects Defective TiO2 undoubtedly represents a significant milestone in the design of photocatalytic materials. However, its transition from laboratory research to practical, large-scale application still faces a series of critical challenges. The main existing problems are outlined as follows.1) Achieving precise and reproducible control over defect structures at the atomic and nanoscale remains exceedingly difficult.No standard has been established for defining an “ideal” defect configuration (including type, density, and spatial distribution) for specific catalytic reactions.2) Many reported high-performance synthesis methods struggle to meet the demands of industrial-scale production due to issues such as energy consumption, cost, and process complexity.Moreover, the chemical and structural stability of these metastable defect structures under harsh operational conditions (e.g., prolonged strong illumination, high temperatures, or oxidative environments) still requires thorough validation. 3) Conventional ex situ characterization techniques are inadequate for capturing the dynamic evolution of defect states and their interactions with reaction intermediates in realtime during catalysis, limiting the in-depth analysis of the life-cycle dynamics of charge carriers.Based on these challenges, this review argues that future research should concentrate on the following core directions: 1) The primary task is to develop simpler, greener, cost-effective, and easily scalable synthesis techniques, while ensuring the long-term stability of the introduced defects under operational conditions. 2) It is imperative to promote the deep integration of advanced in situ/operando characterization techniques, such as synchrotron-based X-ray absorption spectroscopy, environmental transmission electron microscopy, in situ infrared spectroscopy, and positron annihilation spectroscopy, with theoretical calculations (e.g., density functional theory). This integrated approach is essential for dynamically tracking the evolution of defects under realistic reaction conditions, clarifying their mechanistic roles as active centers, and mapping the kinetics of charge carrier separation, migration, and recombination. The goal is to establish accurate “structure-property-performance” correlation maps, laying a solid foundation for the rational design of next-generation photocatalysts. 3) Effortsshould be made to expand the application boundaries of defective TiO2, leveraging its unique physicochemical properties in emerging interdisciplinary fields such as energy storage (e.g., lithium-ion batteries, supercapacitors), high-sensitivity chemical sensing, and biomedicine (e.g., photothermal therapy, antibacterial materials).This expansion will open new research paradigms and market opportunities. Through sustained and deepened interdisciplinary collaboration among chemistry, materials science, physics, and engineering, defective TiO2 nanomaterials hold immense potential to transition from model systems in fundamental research into scalable technological solutions capable of addressing practical energy and environmental problems, making an indispensable contribution to building a sustainable future for humanity.

Keywords: photocatalysis; titanium dioxide; defect regulation; nanomaterial


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