UPS and UV spectroscopies combined to position the energy levels of TiO2 anatase and rutile nanopowders

Positioning of absolute energy levels and the quantitative description of occupied levels obtained for TiO₂ nanopowders, combining UPS and UV-Vis spectroscopies.

Predoped Oxygenated Defects Activate Nitrogen-Doped Graphene for the Oxygen Reduction Reaction

The presence of defects and chemical dopants in metal-free carbon materials plays an important role in the electrocatalysis of the oxygen reduction reaction (ORR). The precise control and design of defects and dopants in carbon electrodes will allow the fundamental understanding of activity-structure correlations for tailoring catalytic performance of carbon-based, most particularly graphene-based, electrode materials. Herein, we adopted monolayer graphene – a model carbon-based electrode – for systematical introduction of nitrogen and oxygen dopants, together with vacancy defects, and studied their roles in catalyzing ORR. Compared to pristine graphene, nitrogen doping exhibited a limited effect on ORR activity. In contrast, nitrogen doping in graphene predoped with vacancy defects or oxygen enhanced the activities at 0.4 V vs the reversible hydrogen electrode (RHE) by 1.2 and 2.0 times, respectively. The optimal activity was achieved for nitrogen doping in graphene functionalized with oxygenated defects, 12.8 times more than nitrogen-doped and 7.7 times more than pristine graphene. More importantly, oxygenated defects are highly related to the 4e^– pathway instead of nitrogen dopants. This work indicates a non-negligible contribution of oxygen and especially oxygenated vacancy defects for the catalytic activity of nitrogen-doped graphene.

Surface, Interface, and Bulk Electronic and Chemical Properties of Complete Perovskite Solar Cells: Tapered Cross-Section Photoelectron Spectroscopy, a Novel Solution

The surface, interface, and bulk properties are a few of the most critical factors that influence the performance of perovskite solar cells. The photoelectron spectroscopy (PES) is used as a technique to analyze these properties. However, the information depth of PES is limited to 10-20 nm, which makes it not suitable to study the complete devices, which have a thickness of ∼1 μm. Here, we introduce a novel and simple technique of PES on a tapered cross section (TCS-PES). It provides both lateral and vertical resolutions compared to the conventional PES so that it is suitable to study a complete perovskite solar cell. It offers many benefits over conventional PES methods such as the chemical composition in the micrometer scale from the surface to the bulk and the electronic properties at the multiple interfaces. The chemical natures of different layers of the perovskite-based solar cells [(FAPbI₃)_0.85(MAPbBr₃)_0.15] can be identified precisely for the first time using the TCS-PES method. We found that the perovskite layer has higher iodine concentration at the Spiro/perovskite interface and higher bromine concentration at the TiO₂/perovskite interface. UPS measurements on the tapered cross section revealed that the perovskite is n-type, and the solar cell studied here is a p-n-n structure type device. The unique possibilities to analyze the complete solar cell by XPS and UPS allow us to estimate the band bending in a working solar cell. Moreover, this technique can further be used to study the device under operating conditions, and it can be applied in other solid-state devices like solid electrolyte Li-ion batteries, LEDs, or photoelectrodes.

Prospective roles for Canadian oncology nurses in breast cancer rapid diagnostic clinics

The introduction of rapid diagnostic clinics for breast cancer increases oncology nurses' (ONs) responsibility for patient education and coordination of multidisciplinary care. Developed as an outcome of the E-Mentorship Oncology Nursing Program, this paper proposes new roles for these nurses to respond effectively and competently to such diagnostic innovation. The Oslo Manual Conceptual Framework of Innovation inspired the idea of change in prospective ONs' roles, corroborated by the Canadian Association of Nurses in Oncology's Standards of Practice and Competencies. New roles for ONs that are informed by the domain of information dynamics and evidence-based care are proposed.

Novel Insights into Enhanced Stability of Li-Rich Layered and High-Voltage Olivine Phosphate Cathodes for Advanced Batteries through Surface Modification and Electron Structure Design

The design of cathode/electrolyte interfaces in high-energy density Li-ion batteries is critical to protect the surface against undesirable oxygen release from the cathodes when batteries are charged to high voltage. However, the involvement of the engineered interface in the cationic and anionic redox reactions associated with (de-)lithiation is often ignored, mostly due to the difficulty to separate these processes from chemical/catalytic reactions at the cathode/electrolyte interface. Here, a new electron energy band diagrams concept is developed that includes the examination of the electrochemical- and ionization- potentials evolution upon batteries cycling. The approach enables to forecast the intrinsic stability of the cathodes and discriminate the reaction pathways associated with interfacial electronic charge-transfer mechanisms. Specifically, light is shed on the evolution of cationic and anionic redox in high-energy density lithium-rich 0.33Li2MnO3·0.67LiNi0.4Co0.2Mn0.4O2 (HE-NCM) cathodes, particularly those that undergo surface modification through SO2 and NH3 double-gas treatment to suppress the structural degradation. The chemical composition and energy distribution of the occupied and unoccupied electronic states at the different charging/discharging states are quantitatively estimated by using advanced spectroscopy techniques, including operando Raman spectroscopy. The concept is successfully demonstrated in designing artificial interfaces for high-voltage olivine structure cathodes enabling stable battery operation up to 5.1 V versus Li+/Li.

Awakening professionals' critical awareness of health literacy issues within a francophone linguistic-minority population in Ontario

INTRODUCTION

We carried out a qualitative evaluation of immediate learning and attitudinal change among health care and social services professionals who attended a workshop promoting critical reflection about health literacy among linguistic-minority Franco-Ontarians.

METHODS

The study involved 41 francophone health care and social services professionals. The workshop facilitator used evocative objects to elicit reflection on health literacy. Data sources were audio-recordings of group discussions and feedback forms completed by participants.

RESULTS

The study found that the workshop awakened participants' awareness of health literacy and stimulated them to promote health literacy in their professional practice. The workshop also broadened participants' vision of health literacy as a social determinant of health that interacts synergistically with culture, age, immigration status, social support, and socioeconomic status.

CONCLUSION

Professionals expressed their awakened awareness of health literacy as collective accountability. This corroborates our claim that critical pedagogy applied to in-service education effectively stimulates professionals' awareness of their potential to change their practice and work environment.

Role of Vacancy Defects and Nitrogen Dopants for the Reduction of Oxygen on Graphene

Disentangling the roles of nitrogen dopants and vacancy defects (VG) in metal-free carbon catalysts for the oxygen reduction reaction (ORR) ideally requires studying both the dopants and defects separately. Here, we systematically introduced nitrogen dopants and VGs via plasma treatment into the basal plane of monolayer graphene as a model carbon catalyst to investigate their specific roles in ORR catalysis. An increased defect density including dopants is positively associated with boosted ORR activity. Nitrogen dopants are responsible for an improved current via a 2e- pathway generating hydroperoxide, while VGs result in enhanced kinetics and water production. We therefore infer that VGs in graphene are responsible for the improved ORR kinetics, while nitrogen dopants majorly influence the selectivity of ORR reaction products. The nitrogen dopants without VGs lead to a higher overpotential compared with the pristine graphene. Instead of the attribution of the ORR active site to only nitrogen species in carbon materials, the improved ORR activity in nitrogen-doped carbon materials should be attributed to the active sites constituted of VGs, oxygen dopants, and nitrogen dopants. Through this work, we provide important insights into the intertwined roles of nitrogen and VGs as well as oxygen dopants in nitrogen-doped metal-free catalysts for a more efficient ORR.

[Uncertainty and hope in seropositive women]

This qualitative research study uses a phenomenological approach to understand the significant of uncertainty and hope in seropositive women and to determine the link between the two. Four seropositive women with children make up the sample. The findings illustrate that uncertainty can be divided into nine themes; reactions on learning or seropositivity; the unknowns of seropositive; the feeling that time and the future are limited; the law of silence; concerns about children; concerns about people withdrawing; concerns about intimate relationships; the image of people living with HIV, and the difficulty experiencing loss--especially loss of control over one's life. The findings also illustrate that hope can be divided into seven themes: seeking assistance through self-help groups; coherence with children; the changing perception of seropositivity; developing relationships with others living with HIV; the fight against HIV; a personal commitment to wellness; and new life experiences and spiritual growth. These findings could be used to determine measures to improve the well-being and health of seropositive women. The authors make recommendations for nursing practice.

Première étape dans l’utilisation de la thérapie par videoconference auprès de survivants du cancer vivant en contexte linguistique minoritaire : une étude pilote

Objectifs : Offrir une thérapie par videoconference pour soulager la peur de la récidive du cancer (PRC) par l’entremise de la vidéoconférence. Déterminer la faisabilité et l’efficacité de ce traitement dans un contexte clinique.

Matériel et méthodes : Thérapie par vidéoconférence cognitivoexistentielle une fois par semaine pour six semaines.

Résultats : Diminution progressive de la PRC et de la détresse psychologique reliée au cancer. Satisfaction adequate de la vidéoconférence.

Conclusion : L’utilisation de la vidéoconférence permettrait à un plus grand nombre de survivants de cancer d’être traités pour leur PRC.

Sol-gel process immobilization of TEMPO catalysts on multi-walled carbon nanotubes for electrocatalytic alcohol oxidation

Immobilizing catalysts on electrodes remains a crucial step in developing electrosynthetic and photoelectrocatalytic systems. An innovative method for immobilizing 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO), functionalized by an alkoxysilane group, around multi-walled carbon nanotubes via a sol-gel reaction is described. The system demonstrates impressive electrocatalytic performance of benzyl alcohols in carbonate buffer at pH 9.