Distinctly Improved Photocurrent and Stability in TiO₂ Nanotube Arrays by Ladder Band Structure

Introducing a ternary interlayer into binary heterostructures to construct a ladder band structure provides a promising way for photoelectrochemical water splitting. Here, we design and fabricate a sandwich structure on TiO₂ nanotubes using CdS_<i>x</i>Se_1–<i>x</i> as the interlayer to obtain a matching band alignment. The photoelectrochemical (PEC) properties of composite photoanodes are optimized by the order of sensitization and elements ratio, wherein the TiO₂/CdS/CdS_0.5Se_0.5/CdSe photoanode shows a significantly enhanced photocurrent of 14.78 mA cm^–2 at −0.2 V vs SCE, exhibiting a nearly 15-fold enhancement, over 1 order of magnitude. The quantum efficiency apparently increases to 40% at a range of 400–520 nm, resulting from the fact that a sensitizing layer with a matching band alignment can facilitate the separation of photogenerated electron–hole pairs and also extend the absorption range to the visible region due to its narrow bandgaps. Furthermore, its stability was distinctly improved by coating MoS₂ on the surface of the TiO₂/CdS/CdS_0.5Se_0.5/CdSe photoanode. Our findings provide a novel route toward developing a highly efficient photoelectrode for water splitting

Rational Engineering Docetaxel Prodrug Nanoassemblies: Response Modules Guiding Efficacy Enhancement and Toxicity Reduction

Prodrug-based nanoassemblies have been developed to solve the bottlenecks of chemotherapeutic drugs. The fabricated prodrugs usually consist of active drug modules, response modules, and modification modules. Among three modules, the response modules play a vital role in controlling the intelligent drug release at tumor sites. Herein, various locations of disulfide bond linkages were selected as response modules to construct three Docetaxel (DTX) prodrugs. Interestingly, the small structural difference caused by the length of response modules endowed corresponding prodrug nanoassemblies with unique characteristic. α-DTX-OD nanoparticles (NPs) possessed the advantages of high redox-responsiveness due to their shortest linkages. However, they were too sensitive to retain the intact structure in the blood circulation, leading to severe systematic toxicity. β-DTX-OD NPs significantly improved the pharmacokinetics of DTX but may induce damage to the liver. In comparison, γ-DTX-OD NPs with the longest linkages greatly ameliorated the delivery efficiency of DTX as well as improved DTX’s tolerance dose