Photoanode is the key issue for photoelectrocatalytic (PEC) water splitting and organics degradation. However, it always faces several restrictions including severe photocorrosion, low charge separation and transfer efficiencies, poor visible light harvesting, and sluggish interfacial reaction kinetics, which often required a variety of modifications with only low improvements achieved. Herein, a high performance CQDs/TiO₂/WO₃ photoanode was designed on the basis of density function theory (DFT) alignment of lattice parameters and energy band, and charge distribution. The TiO₂/WO₃ heterojunction can abate photocorrosion through the hetero-epitaxial growth of TiO₂ (001) on WO₃ (002) for the lattice mismatch < 3 % eliminating dangling bonds, with high corrosion resistance and photostability of TiO₂. As the built-in field constructed by a staggered band alignment structure with the valence band offset (VBO) of 0.51 eV, the photogenerated carriers transfer and separation are promoted dramatically. Through the DFT calculations, the sunlight absorption wavelength can be extended, and the interfacial reaction kinetics can be expedited with the modification of carbon quantum dots (CQDs) on TiO₂/WO₃, due to the narrower bandgap (E_g) and the accumulation of electrons at TiO₂ side. The DFT designed CQDs/TiO₂/WO₃ photoanode significantly increase photocurrent density from 0.90 to 2.03 mA cm^-2 at 1.23 V, charge separation efficiency from 56.3 to 79.2 % and charge injection efficiency from 51.2 to 70.4 %, and extend light absorption edge from 455 to 463 nm over pristine WO₃, with better photostability and lower holes-to-water resistance.

光电阳极是光电催化（PEC）水分解和有机物降解的关键问题。然而，它总是面临着一些限制，包括严重的光腐蚀，低的电荷分离和转移效率，不良的可见光收集以及缓慢的界面反应动力学，这常常需要进行多种 修改，而仅获得很少的改进。在此，基于晶格参数和能带的密度函数理论（DFT）排列以及电荷分布，设计了一种高性能的CQDs / TiO ₂ / WO ₃光电阳极。TiO ₂ / WO ₃异质结可通过TiO ₂（001）在WO ₃上的异质外延生长来减轻光腐蚀。（002）对于晶格失配＜3％，消除了悬空键，具有高的耐腐蚀性和TiO _2的光稳定性。由于由价带偏移（VBO）为0.51 eV的交错带排列结构构成的内置场，光生载流子的转移和分离得到了显着促进。通过DFT计算，由于带隙（E _g）较窄且积聚，可以通过修饰TiO ₂ / WO ₃上的碳量子点（CQDs）来延长日光吸收波长，并加快界面反应动力学。TiO ₂侧的电子数。DFT设计的CQDs / TiO ₂ / WO ₃光电阳极在1.23 V时可将光电流密度从0.90显着提高到2.03 mA cm ^-2，电荷分离效率从56.3提高到79.2％，电荷注入效率从51.2提高到70.4％，并且在原始WO ₃上将光吸收边缘从455 nm扩展到463 nm 。具有更好的光稳定性和较低的抗水孔性。