4 research outputs found
Canadian Familiesâ Decisions of Communication Options* for Children Who are Deaf or Hard of Hearing: An Initial Exploration
Communication is an essential aspect of human interaction and helps connect us to the people around us. The majority of children who are deaf or hard of hearing are born to hearing parents who are likely unfamiliar with hearing loss. These parents are then asked to make critical decisions about communication options for their children. It can be a challenging process but one that needs to be done quickly in order to capture the critical language development period. Little research has explored the factors associated with parentsâ decisions about communication options for their children who are deaf or hard of hearing and no studies have been done specifically with Canadian parents. This exploratory survey design study examined the factors which influence Canadian parentsâ decisions relative to communication options for their children who are deaf or hard of hearing. Results indicate that parentsâ personal judgement and a desire for their child to be able to communicate with their family and be happy in their own unique lives were driving forces behind the decisions that were made. Confirming research conducted in other countries, Canadian parents use a combination of their own judgement, professionalsâ opinions, the needs of their child and internal values to make communication option decisions. Implications of these results are discussed as they pertain to parent-professional partnerships and family-centered services
Predicting Low Toxicity and Scalable Solvent Systems for HighâSpeed RollâtoâRoll Perovskite Manufacturing
Predicting Low Toxicity and Scalable Solvent Systems for High Speed Roll-to-Roll Perovskite Manufacturing
This manuscript introduces solvent toxicity in solar perovskite ink chemistries as a major technoeconomic limitation for the growth of the technology. More specifically, the capital and operational cost of handling such toxic chemicals to maintain a safe working environment can lead to significant added costs. As all record power conversion efficiency devices to date have been solution processed, this represents a major challenge for the perovskite optoelectronic field and of printed electronics as a whole. Knowing this limitation, we propose that solvent selections for ink chemistries should be more quantitative and focus on lowering toxicity. To this end, we show that a Hansen solubility model is effective in predicting ink systems using lower toxicity solvents. We also show that inks formed from this method are applicable for high-speed slot-die coating, limiting the need for long anneal times. These methods and results demonstrate a useful framework for quantitatively engineering solvent systems with reduced toxicity while simultaneously maintaining and surpassing performance. It therefore provides a pathway and major step forward towards the commercialization of solution coated perovskite technologies
High-Speed Vapor Transport Deposition of Perovskite Thin Films
Intensive research of hybrid metal-halide perovskite materials for use as photoactive materials has resulted in an unmatched increase in the power conversion efficiency of perovskite photovoltaics (PVs) over the last couple of years. Now that lab-fabricated perovskite devices rival the efficiency of silicon PVs, the next challenge of scalable mass manufacturing of large perovskite PV panels remains to be solved. For that purpose, it is still unclear which manufacturing method will provide the lowest processing cost and highest quality solar cells. Vapor deposition has been proven to work well for perovskites as a controllable and repeatable thin-film deposition technique but with processing speeds currently too slow to adequately lower the production costs. Addressing this challenge, in the present work, we demonstrate a high-speed vapor transport processing technique in a custom-built reactor that produces high-quality perovskite films with unprecedented deposition speed exceeding 1 nm/s, over 10Ă faster than previous vapor deposition demonstrations. We show that the semiconducting perovskite films produced with this method have excellent crystallinity and optoelectronic properties with 10 ns charge carrier lifetime, enabling us to fabricate the first photovoltaic devices made by perovskite vapor transport deposition. Our experiments are guided by computational fluid dynamics simulations that also predict that this technique could lead to deposition rates on the order of micrometers per second. This, in turn, could enable cost-effective scalable manufacturing of the perovskite-based solar technologies. Keywords: solar cells; perovskite; thin-film; vapor deposition; manufacturing; fluid dynamicsNational Science Foundation (U.S.) (Award 1541959)National Science Foundation (U.S.) (Grant 1605406