Effect of MgO Surface Modification on the TiO₂ Nanowires Electrode for Self-Powered UV Photodetectors

TiO₂-based core–shell structure has gained enormous significance and has developed as a promising candidate in photoelectrochemical (PEC) devices due to its excellent properties. Despite studies, the surface/interface chemistry in these nanostructures has not been fully understood and there is still much room to further improve the performance of related PEC devices. Here, using a closely integrated experimental investigation and mechanism analysis, we scrutinized the intrinsic role of the MgO coating in the photocurrent enhancement of TiO₂@MgO core–shell structured UVPDs. We evidenced that after coating with MgO, the photocurrent of UVPDs has been significantly enhanced and the optimal coating time was found to be 45 min. A large responsivity of 365 mA W^–1 at 360 nm and a simultaneously excellent on/off ratio of 16 739 are achieved, which have rarely reported previously. In addition, the structure–property relationships are well established in all studied UVPDs through comparing investigations. The superior performance is postulated to be strongly correlated to the suppression of the recombination of photogenerated electron with I₃^– in electrolyte. This work sheds some light on searching for new structures for next-generation low cost, large area, and energy-efficient optoelectronic devices

<i>In Vivo</i> Architectonic Stability of Fully <i>de Novo</i> Designed Protein-Only Nanoparticles

The fully <i>de novo</i> design of protein building blocks for self-assembling as functional nanoparticles is a challenging task in emerging nanomedicines, which urgently demand novel, versatile, and biologically safe vehicles for imaging, drug delivery, and gene therapy. While the use of viruses and virus-like particles is limited by severe constraints, the generation of protein-only nanocarriers is progressively reachable by the engineering of protein–protein interactions, resulting in self-assembling functional building blocks. In particular, end-terminal cationic peptides drive the organization of structurally diverse protein species as regular nanosized oligomers, offering promise in the rational engineering of protein self-assembling. However, the <i>in vivo</i> stability of these constructs, being a critical issue for their medical applicability, needs to be assessed. We have explored here if the cross-molecular contacts between protein monomers, generated by end-terminal cationic peptides and oligohistidine tags, are stable enough for the resulting nanoparticles to overcome biological barriers in assembled form. The analyses of renal clearance and biodistribution of several tagged modular proteins reveal long-term architectonic stability, allowing systemic circulation and tissue targeting in form of nanoparticulate material. This observation fully supports the value of the engineered of protein building blocks addressed to the biofabrication of smart, robust, and multifunctional nanoparticles with medical applicability that mimic structure and functional capabilities of viral capsids