Computer Engineering | Open Access Articles | Digital Commons Network™

Light-Activated Photocurrent Degradation And Self-Healing In Perovskite Solar Cells, Wanyi Nie, Jean-Christophe Blancon, Amanda J. Neukirch, Kannatassen Appavoo, Hsinhan Tsai, Manish Chhowalla, Muhammad A. Alam, Matthew Y. Sfeir, Claudine Katan, Jacky Even, Sergei Tretiak, Jared J. Crochet, Gautam Gupta, Aditya D. Mohite May 2016

Light-Activated Photocurrent Degradation And Self-Healing In Perovskite Solar Cells, Wanyi Nie, Jean-Christophe Blancon, Amanda J. Neukirch, Kannatassen Appavoo, Hsinhan Tsai, Manish Chhowalla, Muhammad A. Alam, Matthew Y. Sfeir, Claudine Katan, Jacky Even, Sergei Tretiak, Jared J. Crochet, Gautam Gupta, Aditya D. Mohite

Publications and Research

Solution-processed organometallic perovskite solar cells have emerged as one of the most promising thin-film photovoltaic technology. However, a key challenge is their lack of stability over prolonged solar irradiation. Few studies have investigated the effect of light soaking on hybrid perovskites and have attributed the degradation in the optoelectronic properties to photochemical or field-assisted ion migration. Here we show that the slow photocurrent degradation in thin-film photovoltaic devices is due to the formation of light-activated meta-stable deep-level trap states. However, the devices can self-heal completely by resting them in the dark for <1 min or the degradation can be completely prevented by operating the devices at 0°C. We investigate several physical mechanisms to explain the microscopic origin for the formation of these trap states, among which the creation of small polaronic states involving localized cooperative lattice strain and molecular orientations emerges as a credible microscopic mechanism requiring further detailed studies.

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Framing The Question, "Who Governs The Internet?", Robert J. Domanski Jan 2015

Framing The Question, "Who Governs The Internet?", Robert J. Domanski

Publications and Research

There remains a widespread perception among both the public and elements of academia that the Internet is “ungovernable”. However, this idea, as well as the notion that the Internet has become some type of cyber-libertarian utopia, is wholly inaccurate. Governments may certainly encounter tremendous difficulty in attempting to regulate the Internet, but numerous types of authority have nevertheless become pervasive. So who, then, governs the Internet? This book will contend that the Internet is, in fact, being governed, that it is being governed by specific and identifiable networks of policy actors, and that an argument can be made as to …

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Mobile Apps In Collection Development: Supporting A Mobile Learning Environment, Stefanie Havelka, Rebecca Arzola Jan 2015

Mobile Apps In Collection Development: Supporting A Mobile Learning Environment, Stefanie Havelka, Rebecca Arzola

Publications and Research

We will discuss our rationale and thoughts on why we believe mobile apps should be part of a library’s collection development policy. An updated policy with apps encourages a mobile learning environment that is technologically diverse while being holistically supportive of its users and research.

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Mobile First Web And Content Strategy, Stefanie Havelka, David Stevens Nov 2012

Mobile First Web And Content Strategy, Stefanie Havelka, David Stevens

Publications and Research

The paradigm shift from the traditional desktop to the mobile web experience is fast approaching, and providing relevant date, location and time-sensitive content to users via mobile devices becomes an essential piece of the overall web strategy. This presentation demonstrates the concepts, techniques and technologies used to develop both the overall mobile content strategy and user experience, as well as the aggregation and delivery of content to both the desktop and mobile form factors from a single content source.

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Application Planning, Jochen Albrecht, Clare Davies Jan 2010