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Realization of the full potential of single‐atom photoelectrocatalysts in sustainable energy generation requires careful consideration of the design of the host material. Here, a comprehensive methodology for the rational design of photoelectrocatalysts using anodic titanium dioxide (TiO2) nanofilm as a model platform is presented. The properties of these nanofilms are precisely engineered to elucidate synergies across structural, chemical, optoelectronic, and electrochemical properties to maximize the efficiency of the hydrogen evolution reaction (HER). These findings clearly demonstrate that thicker TiO2 nanofilms in anatase phase with pits on the surface can accommodate single‐atom platinum catalysts in an optimal configuration to increase HER performance. It is also evident that the electrolyte temperature can further enhance HER output through thermochemical effect. A judicious design incorporating all these factors into one system gives rise to a ten‐fold HER enhancement. However, the reusability of the host photoelectrocatalyst is limited by the leaching of the Pt atom, worsening HER. Density‐functional theory calculations have provided insights into the mechanism underlying the experimental observations in terms of moderate hydrogen adsorption and enhanced gas generation. This improved understanding of the critical factors determining HER performance in a model photoelectrocatalyst paves the way for future advances in scalable and translatable photoelectrocatalyst technologies. [ABSTRACT FROM AUTHOR]

In this study, nanoporous anodic alumina distributed‐Bragg reflectors (NAA–DBRs) functionalized with tungsten trioxide (WO3) are used as prototype photoelectrocatalysts (PEC) for harnessing the slow photon effect to maximize photon‐to‐electron conversion efficiency under UV–visible–NIR illumination. NAA–DBR structures are structurally engineered by anodization, where their characteristic photonic stopband is precisely tuned along specific positions of the UV–visible spectrum. Subsequent atomic layer deposition is employed to coat the inner surface of these porous structures with WO3 semiconductor layers. Upon the application of overpotential bias, these platforms reveal excellent electron–hole pair separation to boost photoelectrocatalytic reactions. Photoelectrochemical degradation of methylene blue is used as a model reaction to elucidate enhancements associated with structural and optoelectronic arrangements. Notably, precise spectral alignment between the photonic stopband's red edge and the absorbance band of methylene blue enhances the degradation performance through the slow photon effect. Applying an overpotential bias further improves the photodegradation performance through efficient charge separation. These systems outperform comparable structures in this model reaction, achieving a maximum kinetic rate of 13.7 ± 2.0 h−1. The findings create new opportunities to develop high‐performing PEC technologies harnessing light–matter interactions. [ABSTRACT FROM AUTHOR]

A series of β‐strand peptides comprising redox‐active amino acids in the P2 position were synthesized to investigate the effects of electron‐rich side chains on charge transfer and possible coupling interactions between side chains. Electrochemical results indicated a direct link between aromaticity of the side chains and electron transfer rate constants, while single‐molecule conductance studies supported the ability of the electron‐rich side chains to behave as 'stepping stones' to facilitate electron transfer through the peptides. Additional electrochemical analysis of the analogue containing D‐Tyr in the P2 position was undertaken at various pH levels and revealed intramolecular coupling interaction between the side chains, providing further insights on proton coupled electron transfer (PCET). These findings progress the established fundamental knowledge of charge transfer kinetics and explore new pathways for advancement in the architecture of molecular‐based electronic components and devices. [ABSTRACT FROM AUTHOR]

A novel strategy to treat Staphylococcus aureus (S. aureus) skin infections is presented, where UV light is used to facilitate concomitant light‐controlled activation and delivery of an antimicrobial therapeutic agent. Specifically, a new photoswitchable gramicidin S analogue was immobilized onto a polymeric wearable patch via a photocleavable linker that undergoes photolysis at the same wavelength of light required for activation of the peptide. Unlike toxic gramicidin S, the liberated active photoswitchable peptide exhibits antimicrobial activity against S. aureus while being ostensibly non‐haemolytic to red blood cells. Moreover, irradiation with visible light switches off the antimicrobial properties of the peptide within seconds, presenting an ideal strategy to regulate antibiotic activity for localized bacterial infections with the potential to mitigate resistance. [ABSTRACT FROM AUTHOR]