Journal of Photochemistry and Photobiology C: Photochemistry Reviews最新文献

This paper describes overview of electrofluorochromism, which is a phenomenon that controls photoluminescence through a change in the redox states of functional molecules, metal complexes, polymeric films, etc. Electrofluorochromic materials are considered prospective innovative materials because they can convert electrical input into intuitive visual signals. This field opens novel systems by combining absorption, reflection, and luminescence properties, leading to high contrast, night and day visibility, low-cost displays, and various sensing applications. The former sections provided a short overview of the electrofluorochromic phenomena and observation setups. The electrofluorochromic reactions and devices synchronized with the absorption change based on the electrochemical reaction we reported were also reviewed.

Semiconductor materials containing bismuth have attracted the attention of researchers over the past several decades, as a result of their high photocatalytic activity in various reactions and/or high efficiency in their photoelectric conversion of solar energy. This interest originated from the observations that bismuth-containing semiconductors have a sufficiently small bandgap, which makes them sensitive to radiation in the visible spectral range; thus, visible-light-active materials. Among the various bismuth-containing semiconductor materials, the bismuthates of alkaline earth metals are distinguished and describe into separate groups. This article reviews research on the known methods of obtaining bismuthates of various alkaline earth metals (magnesium, calcium, strontium, and barium), and further analyzes their composition, structure, and visible-light-active photocatalytic activity.

Visible-light photocatalysis offers unique opportunities to achieve smooth and clean functionalization of organic compounds by unlocking site-specific reactivities, generally under mild reaction conditions. This review offers a critical assessment of current literature, pointing out the recent developments and potential applications in the field of photocatalysis as well as its utilization in the field of organic synthesis for expected future progress.

Circularly polarized (CP) light, as a special form of polarized light, demonstrates potential application prospects in future displays and optoelectronic technologies. Circularly polarized luminescence (CPL) from chiral chromophores is an ideal method to directly generate CP light, but how to design efficient emitters is always a perplexing problem. Among various chiral materials, CPL materials with axial chirality can provide us with clear structural parameters and information to further explore the structure-activity relationship. Herein, we systematically summarize the development status of axially chiral compounds with CPL properties from two aspects of photoluminescence and electroluminescence, covering metal complexes, polymers, supramolecular assemblies, simple organic molecules, and liquid crystals systems. In addition, we initially explore the relationship between CPL performance and axially chiral configuration, and the current challenges and opportunities in this vibrant field are also discussed.

Photodynamic therapy (PDT) and photodynamic antimicrobial chemotherapy (PACT) combine light and photosensitizers to treat cancers and microbial infections, respectively. In PACT, the excitation of a photosensitizer drug with appropriate light generates reactive oxygen species (ROS) that kill pathogens in the proximity of the drug. PACT has considerably advanced with new light sources, biocompatible photosensitizers, bioconjugate methods, and efficient ROS production. The PACT technology has evolved to compete with or replace antibiotics, reducing the burden of antibiotic resistance. This review updates recent advances in PACT, with special references to light sources, photosensitizers, and emerging applications to microbial infestations. We also discuss PACT applied to COVID-19 causing SARS-CoV-2 treatment and disinfecting food materials and water. Finally, we discuss the pathogen selectivity and efficiency of PACT.

Hydrogen plays an important role in developing a clean and sustainable future energy scenario. Substantial efforts to produce green hydrogen from water splitting, biomass and hydrogen sulfide (H₂S) have been made in recent years. H₂S, naturally occurring or generated in fuel gas processing and industrial wastewater treatment, can be split into hydrogen and sulfur via photocatalysis. Although it is not as widely used as water splitting for green hydrogen production, this process is considered to be an appropriate and sustainable way to meet the future energy demands, adding value to H₂S. Therefore, it is essential to understand how to improve the solar light utilization and splitting efficiency of H₂S based on the existing technology and materials. Along with that effort, molecular modeling and theoretical calculations are indispensable tools to provide guidance to effectively design photocatalysts for improving hydrogen generation efficiency. In this review, we summarize the published work on H₂S photocatalysis modeling and illustrate the use of different computational methods to gain more in-depth insight into the reaction mechanisms and processes. Moreover, an overview of quantum mechanical and molecular simulation approaches combined with other modeling techniques, relevant to material science and catalysis design and applicable to H₂S splitting is also presented. Challenges and future directions for developing H₂S splitting photocatalysts are highlighted in this contribution, which is intended to inspire further simulation developments and experiments for H₂S splitting, tailoring photocatalysts design towards highly efficient hydrogen production.

Over the years, microorganisms have developed several resistance mechanisms against standard treatments, thus limiting the effect of drugs and rendering ineffective therapies. Considering the growing number of resistant pathogens and adverse effects of conventional therapies, new antimicrobial technologies able to provide more effective, rapid, and safer treatments to inactivate pathogens, with unlikely chances of inducing resistance, are needed. In this regard, antimicrobial photodynamic inactivation (aPDI) has emerged as an alternative modality of treatment. In particular, Zn(II) porphyrins (ZnPs) hold great potential as photosensitizers (PSs) for aPDI and have been attracting increasing attention. The chemical structure of ZnPs can be tailored to produce PSs with improved chemical stability and photophysical properties, also modulating their amphiphilic and ionic characters, bioavailability, and (sub)cellular distribution. Thus, in this review, we provide a detailed report of studies published in about the last 10 years (2010–2021) focusing on aPDI mediated by ZnPs over a variety of pathogens, including bacteria, fungi, viruses, and protozoa. Fundamentals of aPDI, and porphyrin and its derivatives, especially ZnPs, are also included herein. We hope that this review can guide and be a reference for future studies related to aPDI mediated by ZnPs, and encourages more detailed studies on ZnP photophysical and photochemical properties, aiming to improve the fight against infectious diseases.

Solar energy conversion is inciting tremendous research efforts in many fields due to the vast potential of sunlight as a sustainable energy source. For solar energy to become widely used and become a major component of our energy mix, energy storage on large scales must be addressed and the components used must be abundant. Artificial photosynthesis to produce solar fuels holds promise as a way to convert solar energy into storable energy. Organic photocatalysts have rapidly established themselves as a viable alternative to inorganic systems. Organic photocatalyst can be prepared from inexpensive precursors and offer a synthetic versatility and tunability that can be exploited to improve efficiencies. Carbon nitride (CN_x) has emerged as a leading organic photocatalyst with advantageous chemical and photo stabilities. Recombination of photogenerated electrons and holes limit the efficiency of CN_x materials below levels necessary to become a viable energy production system. To improve the efficiency and key characteristics such as light harvesting, charge carrier lifetime, and interfacial rate of charge transfer, a second material is put in contact with CN_x to form a heterojunction. While there are many examples of heterojunctions improving the photocatalytic activity beyond that of the isolated CN_x, we are still lacking the deep understanding of charge carrier dynamics necessary to rationalize the improvements and design optimal junctions. This review covers the studies of CN_x heterojunctions that have used optical methods to monitor the charge carrier dynamics. Time-resolved photoluminescence (TRPL) is the most common technique used and there are many examples that have used transient absorption spectroscopy (TAS) to probe the charge carrier dynamics. However, attempting to link the lifetime change to the activity differences does not yield a clear trend. It is likely that the reactive charges are not consistently being monitored and is obscuring the expected correlations. Both shorter and longer charge carrier lifetimes can be observed with both TRPL and TAS techniques and can be interpreted as arising from interfacial charge separation. Even when the same materials are used in the junction there is no consistency in observing a shorter or longer lifetime. The holistic view of charge carrier dynamics in CN_x heterojunctions presented here intends to identify overarching themes from a wide range of CN_x-containing systems and help take stock of where our current understanding stands. More specific spectral assignments and linking the observed lifetimes to certain photophysical or photochemical processes are needed to build models to help us understand the links between the charge carrier dynamics and the activity. These are crucial to develop general strategies that will lead to optimal CN_x heterojunctions.