Impacts of Post-metallisation Processes on the Electrical and Photovoltaic Properties of Si Quantum Dot Solar Cells

As an important step towards the realisation of silicon-based tandem solar cells using silicon quantum dots embedded in a silicon dioxide (SiO2) matrix, single-junction silicon quantum dot (Si QD) solar cells on quartz substrates have been fabricated. The total thickness of the solar cell material is 420 nm. The cells contain 4 nm diameter Si quantum dots. The impacts of post-metallisation treatments such as phosphoric acid (H3PO4) etching, nitrogen (N2) gas anneal and forming gas (Ar: H2) anneal on the cells’ electrical and photovoltaic properties are investigated. The Si QD solar cells studied in this work have achieved an open circuit voltage of 410 mV after various processes. Parameters extracted from dark I–V, light I–V and circular transfer length measurement (CTLM) suggest limiting mechanism in the Si QD solar cell operation and possible approaches for further improvement

Optical characterisation of silicon nanocrystals embedded in SiO2/Si3N4 hybrid matrix for third generation photovoltaics

Silicon nanocrystals with an average size of approximately 4 nm dispersed in SiO2/Si3N4 hybrid matrix have been synthesised by magnetron sputtering followed by a high-temperature anneal. To gain understanding of the photon absorption and emission mechanisms of this material, several samples are characterised optically via spectroscopy and photoluminescence measurements. The values of optical band gap are extracted from interference-minimised absorption and luminescence spectra. Measurement results suggest that these nanocrystals exhibit transitions of both direct and indirect types. Possible mechanisms of absorption and emission as well as an estimation of exciton binding energy are also discussed

On PAR: A feasibility study of the Promoting Adult Resilience programme with mental health nurses

© 2018 Australian College of Mental Health Nurses Inc. Mental health settings are recognized as complex, unpredictable environments, and challenging interpersonal situations are common for nurses in acute adult mental health services. Occupational stressors include verbal aggression and physical assault and are correlated with poor physical and mental health outcomes for nurses. There is a clear need for proactive approaches that address the negative impacts of stressors on the mental health nursing workforce. Resilience interventions are a preventive approach to strengthening skills for addressing workplace stress, improving health and well-being, and preventing adverse outcomes associated with occupational stressors. The aim of this study was to evaluate the feasibility of a workplace resilience education programme for nurses in high-acuity adult mental health settings. The outcomes were measured using a single-group pretest post-test design with follow-up at 3 months postintervention. The feasibility and acceptability of the programme were identified with descriptors of mental health, well-being, resilience, facilitator fidelity checklists, and participant satisfaction questionnaires. The programme was found to be feasible for nurses working in high-acuity inpatient settings. There were significant changes to mental health, well-being, and workplace resilience. The programme was delivered with fidelity by facilitators and accepted with high levels of satisfaction by participants. The study findings indicated that nurses can benefit from resilience education that equips them with cognitive, emotion regulation, and relational skills, in conjunction with available external supports and resources, to address workplace challenges. There is a need for comprehensive organizational approaches that include individual, work unit, and organizational-level strategies to support staff well-being

Hybrid solar energy harvesting and storage devices: The promises and challenges

Hybrid devices that can harvest solar energy and store that energy electrochemically to provide a source of power are increasingly attracting attention due to their potential to provide autonomous power sources. Of particular interest is their ability to support sensors for the Internet of Things (IoT), wearable electronics and autonomous medical monitoring. Many such hybrid devices have been reported, however challenges exist with respect to electrode arrangements and operating modes, form factors, material compatibility and durability. In this perspective, we review both the application potential and design/fabrication challenges for this class of device. It is proposed that device architecture and material choices need to be carefully selected according to the specific intended application to ensure adequate durability and offer practical outcomes over alternative solutions comprising individual solar harvesting and energy storage devices

Kinetics studies of thin film amorphous titanium niobium oxides for lithium ion battery anodes

Amorphous titanium niobium oxides (TNOs) with varying ratios of Ti and Nb (Ti4Nb2O13, Ti2Nb2O9 and TiNb2O7) are presented as promising anode materials for Li ion batteries. The capacity of the TNO materials is seen to be equivalent to, or larger than, that of the binary oxides, with average volumetric capacities over the first 10 cycles of 717, 1,039 and 925 mAh cm−3 for amorphous Ti4Nb2O13, Ti2Nb2O9 and TiNb2O7, respectively at a current density of 0.2 A cm−3, compared to 720 mAh cm−3 and 425 mAh cm−3 for amorphous TiO2 and Nb2O5. Using densities estimated with X-ray reflectometry, these are equivalent to gravimetric capacities of 231, 335, 319 mAh g−1 for amorphous Ti4Nb2O13, Ti2Nb2O9 and TiNb2O7, respectively at a current density of ~70 mA g−1, compared to 257 mAh g−1 and 137 mAh g−1 for amorphous TiO2 and Nb2O5 at a current density ~80 mA g−1 and ~50 mA g−1, respectively. We discuss how rate capability varies with varying ratios of Ti and Nb and relate this to electrochemical parameters determined by the potentiostatic intermittent titration technique. Our findings reveal that the rate capability of the films is dominated by the diffusion resistance, RD, a composite parameter linked to the insertion rate and diffusion coefficient of Li, leading to a conclusion that the rate retention of the thin films is dominated by the density of insertion sites and the insertion reaction more generally

Researching a whole school approach to school connectedness

This paper reports on a participatory action research project that investigated how a resource called the Index for Inclusion was used by a secondary school community to improve school connectedness at a whole school level. The researchers worked with the Australian case study school over one year to engage in review, development, and change. This paper reports on the procedure of working with the School Connectedness Committee through the five phases of the participatory action research. Data are organised under the theme of ‘building community’ with the sub-themes of ‘positive relationships with staff’ and ‘student leadership’. The findings from this case study indicate that the implementation of the five phases of the Index for Inclusion can support a whole school approach to build a sense of community that supports young people to be more connected to their school.</p

A School-Based Approach to Building Resilience and Mental Health Among Adolescents on the Autism Spectrum: A Longitudinal Mixed Methods Study

Tackling mental health difficulties in adolescents on the autism spectrum requires a comprehensive prevention approach. A 3-year multisite proof-of-concept longitudinal study implemented an evidence-based multilevel resilience intervention in schools to promote protective factors at the adolescent, parent, and school level. The intervention, consisting of the adolescent, parent and teacher components of the Resourceful Adolescent Program–Autism Spectrum Disorder (RAP-ASD) augmented with the Index for Inclusion, was implemented in 6 secondary schools with 30 adolescents with an autism diagnosis in Grades 7 and 8, 31 parents of 23 of the adolescents, and school staff. The intervention was implemented with good validity and acceptability. Quantitative data from adolescents and parents were analysed using the Reliable Change Index, and qualitative data were analysed using Consensual Qualitative Research. Triangulated quantitative and qualitative outcomes from the majority of adolescents and their parents showed some evidence for promoting resilience for adolescents with a diagnosis or traits of autism, as reflected in reliable improvements in coping self-efficacy and school connectedness, and a reduction in anxiety symptoms and emotional and behavioural difficulties. A reliable improvement in depressive symptoms was more modest and was only achieved by a small minority of adolescents. This multilevel, strength-focused, resilience-building approach represents a promising and sustainable school-based primary prevention program to improve the quality of life for adolescents on the spectrum by promoting their mental health and providing their families with much needed support

Differential Effects of Polyphenols on Insulin Proteolysis by the Insulin-Degrading Enzyme

The insulin-degrading enzyme (IDE) possesses a strong ability to degrade insulin and Aβ42 that has been linked to the neurodegeneration in Alzheimer’s disease (AD). Given this, an attractive IDE-centric strategy for the development of therapeutics for AD is to boost IDE’s activity for the clearance of Aβ42 without offsetting insulin proteostasis. Recently, we showed that resveratrol enhances IDE’s activity toward Aβ42. In this work, we used a combination of chromatographic and spectroscopic techniques to investigate the effects of resveratrol on IDE’s activity toward insulin. For comparison, we also studied epigallocatechin-3-gallate (EGCG). Our results show that the two polyphenols affect the IDE-dependent degradation of insulin in different ways: EGCG inhibits IDE while resveratrol has no effect. These findings suggest that polyphenols provide a path for developing therapeutic strategies that can selectively target IDE substrate specificity