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Time-resolved photoluminescence (TRPL) is a powerful tool to investigate charge carrier recombination processes in emissive materials. Perovskite materials are extremely promising for applications in solar cells; however, the interpretation of their TRPL is arduous due to the complicated nature of the recombination processes occurring in these materials. We present here the PErovskite cArrier Recombination Simulator (PEARS) web tool for effortlessly and quickly fitting TRPL of perovskite materials using advanced charge carrier recombination models, allowing for the extraction of recombination rate constants and trap state concentration. PEARS is flexible and can adapt to different situations, by ignoring recombination processes or fixing known parameters (e.g., the doping concentration). The tool is publicly available at https://pears-tool.herokuapp.com.

Ruthenium(II) polypyridyl complexes (RPCs) that emit from metal-to-ligand charge transfer (MLCT) states have been developed as DNA probes and are being examined as potential anticancer agents. Here, we report that MLCT-emissive RPCs that bind DNA undergo Förster resonance energy transfer (FRET) with Cy5.5-labeled DNA, forming mega-Stokes shift FRET pairs. Based on this discovery, we developed a simple and rapid FRET binding assay to examine DNA-binding interactions of RPCs with diverse photophysical properties, including non-“light switch” complexes [Ru(dppz)2(5,5′dmb)]2+and [Ru(PIP)2(5,5′dmb)]2+(dppz = dipyridophenazine, 5,5′dmb = 5,5′-dimethyl-2,2′-bipyridine, PIP = 2-phenyl-imidazo[4,5-f][1,10]phenanthroline). Binding affinities toward duplex, G-quadruplex, three-way junction, and mismatch DNA were determined, and derived FRET donor–acceptor proximities provide information on potential binding sites. Molecules characterized by this method demonstrate encouraging anticancer properties, including synergy with the PARP inhibitor Olaparib, and mechanistic studies indicate that [Ru(PIP)2(5,5′dmb)]2+acts to block DNA replication fork progression.

People with Parkinson’s disease (PD) have higher rates of hospitalisation and healthcare utilisation compared to the general population. The COVID-19 pandemic caused significant changes in admissions to hospital and access to healthcare. People with PD are some of the most vulnerable to such changes. There is no pre-existing data on the cause and duration of admission to hospital of people with PD during the COVID-19 pandemic. To determine the cause, duration, and outcome of hospital admissions to Northumbria Healthcare NHS Foundation Trust (NHCFT) for people with idiopathic Parkinson’s disease (IPD) in 2020. All people with IPD who had an emergency admission to NHCFT between 01/01/2020 and 31/12/2020 were identified. Demographic and disease characteristics, the number, duration, cause of admission and the location prior to admission were collected from an audit of medical notes. 271 people with IPD had one or more emergency admissions to NHCFT between 01/01/2020 and 31/12/2020. There was a total of 453 emergency admissions, with a median duration of 5 (IQR 2-13) days. The most common causes of admission to hospital were PD-related motor dysfunction (includes falls with no other underlying cause or associated injury) and injury (includes falls with fracture), at 78 (17.2%) and 70 (15.5%) respectively. People with IPD had a short duration but high number of emergency admissions to hospital. Our chronological data on number of admissions shows a peak in admissions during August 2020. As a result of these findings and emerging data we suggest that individuals with PD deconditioned during 2020.

Synergistic effects of the electronic structure and morphology in the PTB7-Th polymer and the nonfullerene acceptor ITIC molecule resulted in state-of-art systems for organic solar cells, achieving over 12% power conversion efficiency (PCE) values. Furthermore, the substitution of harmful halogenated solvents to environmentally friendly solvents that do not compromise PCE values has become a subject of great interest in recent literature. In this work, we employed sulfur K-edge Angle-Resolved Near-Edge X-ray Absorption Fine Structure, Resonant Auger Spectroscopy, and the core-hole clock spectroscopy in an attempt to gain information on the effect of different processing methods on the electronic and morphological properties of these systems. Comparison with the PTB7-Th:PCBM blend, which uses a conventional acceptor molecule, was also performed. Steady-state and time-resolved photoluminescence results were obtained for neat PTB7-Th and blends with ITIC and PCBM. Theoretical calculations were performed utilizing restricted-excitation-window time-dependent density functional theory. Our results shows that ortho-methylanisole is a potential replacement to the conventional halogenated solvent ortho-dichlorobenzene, as they show that in terms of morphology and charge transfer dynamics, no expressive changes occurred by varying the solvent and by thermal annealing.

Parkinson’s disease (PD) is a multi-system disorder that can impact on driving ability. Little is known about how these changes in driving ability affect people with PD, making it difficult for clinicians and carers to offer appropriate support. To assess patient views concerning the effect of PD on their driving ability, the impact of these changes and how they manage them. An online survey was created by a team of clinicians, people with PD, their carers, and representatives from Parkinson’s UK. People with PD throughout the United Kingdom were invited to participate through Parkinson’s UK’s website, newsletter and Parkinson’s Excellence Network email list. 805 people with PD took part in the survey. We found that the loss of a driving licence had an adverse impact on employment, socialisation, travel costs and spontaneous lifestyle choices. Multiple changes in driving ability related to PD were described, including that impulse control disorders can have an adverse impact on driving. Changes in driving ability caused people to change their driving practices including taking shorter journeys and being less likely to drive at night. Participants advised managing changes in driving ability through planning, vehicle adaptions, maintaining skills and self-assessment. This study demonstrates the impact that changes in driving ability can have on the lifestyle of people with PD and reveals the strategies that individuals adopt to manage these changes.

Zero-valent copper (Cu0) is a promising co-catalyst in semiconductor-based photocatalysis as it is inexpensive and exhibits electronic properties similar to those of Ag and Au. However, its practical application in photocatalytic hydrogen production is limited by its susceptibility to oxidation, forming less active Cu species. Herein, we have carried out in situencapsulation of Cu0nanoparticles with N-graphitic carbon layers (14.4% N) to stabilize Cu0nanoparticles (N/C-coated Cu) and improve the electronic communication with a TiO2photocatalyst. A facile solvothermal procedure is used to coat the Cu0nanoparticles at 200 °C, while graphitization is achieved by calcination at 550 °C under an inert atmosphere. The resultant N/C-coated Cu/TiO2composites outperform the uncoated Cu counterparts, exhibiting a 27-fold enhancement of the hydrogen evolution rate compared to TiO2and achieving a rate of 19.03 mmol g–1h–1under UV–vis irradiation. Likewise, the N/C-coated Cu co-catalyst exhibits a less negative onset potential of −0.05 V toward hydrogen evolution compared to uncoated Cu (ca. −0.30 V). This superior activity is attributed to coating Cu0with N/C, which enhances the stability, electronic communication with TiO2, conductivity, and interfacial charge transfer processes. The reported synthetic approach is simple and scalable, yielding an efficient and affordable Cu0co-catalyst for TiO2.

We present a controlled, stepwise formation of methylammonium bismuth iodide (CH3NH3)3Bi2I9perovskite films prepared via the vapour assisted solution process (VASP) by exposing BiI3films to CH3NH3I (MAI) vapours for different reaction times, (CH3NH3)3Bi2I9semiconductor films with tunable optoelectronic properties are obtained. Solar cells prepared on mesoporous TiO2substrates yielded hysteresis-free efficiencies upto 3.17% with good reproducibility. The good performance is attributed mainly to the homogeneous surface coverage, improved stoichiometry, reduced metallic content in the bulk, and desired optoelectronic properties of the absorbing material. In addition, solar cells prepared using pure BiI3films without MAI exposure achieved a power conversion efficiency of 0.34%. The non-encapsulated (CH3NH3)3Bi2I9devices were found to be stable for as long as 60 days with only 0.1% drop in efficiency. This controlled formation of (CH3NH3)3Bi2I9perovskite films highlights the benefit of the VASP technique to optimize material stoichiometry, morphology, solar cell performance, and long-term durability.

The photochemistry and stability of fullerene films is found to be strongly dependent upon film nanomorphology. In particular, PC61BM blend films, dispersed with polystyrene, are found to be more susceptible to photobleaching in air than the more aggregated neat films. This enhanced photobleaching correlated with increased oxygen quenching of PC61BM triplet states and the appearance of a carbonyl FTIR absorption band indicative of fullerene oxidation, suggesting PC61BM photo-oxidation is primarily due to triplet-mediated singlet oxygen generation. PC61BM films were observed to undergo photo-oxidation in air for even modest (≤40 min) irradiation times, degrading electron mobility substantially, indicative of electron trap formation. This conclusion is supported by observation of red shifts in photo- and electro-luminescence with photo-oxidation, shown to be in agreement with time-dependent density functional theory calculations of defect generation. These results provide important implications on the environmental stability of PC61BM-based films and devices.

To celebrate the centenary ofScience Progress we offer a short survey of the progress made over the past one hundred years in the research and application of photoinduced charge transfer. After a brief historical overview and introduction to photoinduced charge transfer, we discuss developments in the theory and practice of photography, photovoltaics, photocatalysis, fluorescent probes and chemosensing.