Involving Students in a Collaborative Project To Help Discover Inexpensive, Stable Materials for Solar Photoelectrolysis

In general, laboratory experiments focus on traditional chemical disciplines. While this approach allows students the ability to learn and explore fundamental concepts in a specific area, it does not always encourage students to explore interdisciplinary science. Often little transfer of knowledge from one area to another is observed, as students are given step-by-step instructions on how to complete their task with little involvement or problem solving. Herein, we provide an example of a real-time research laboratory experiment that is aimed at individual’s exploration and development, with the scientific goal of discovering inexpensive, stable oxide semiconductors that can efficiently photoelectrolyze water to a useable fuel, hydrogen. Students create unique metal oxide semiconductors combinations, scan the samples for photoactivity using a purchased scan station, and report their findings to a collaborative database. A distinctive feature of the project is its ability to be implemented in a variety of educational levels with a breadth and depth of material covered accordingly. Currently, kits are being used in secondary education classrooms, at undergraduate institutions, or as outreach activities. The project provides students and scientists from different disciplines the opportunity to collaborate in research pertaining to clean energy and the global energy crisis

Quantitative Reasoning in Environmental Science: Rasch Measurement to Support QR Assessment

Original work is hosted at USF Libraries Scholar Commons publisher of Numeracy, the electronic journal of the National Numeracy Network (NNN). Abstract : The ability of middle and high school students to reason quantitatively within the context of environmental science was investigated. A quantitative reasoning (QR) learning progression, with associated QR assessments in the content areas of biodiversity, water, and carbon, was developed based on three QR progress variables: quantification act, quantitative interpretation, and quantitative modeling. Diagnostic instruments were developed specifically for the progress variable quantitative interpretation (QI), each consisting of 96 Likert-scale items. Each content version of the instrument focused on three scale levels (macro scale, micro scale, and landscape scale) and four elements of QI identified in prior research (trend, translation, prediction, and revision). The QI assessments were completed by 362, 6th to 12th grade students in three U.S. states. Rasch (1960/1980) measurement was used to determine item and person measures for the QI instruments, both to examine validity and reliability characteristics of the instrument administration and inform the evolution of the learning progression. Rasch methods allowed identification of several QI instrument revisions, including modification of specific items, reducing number of items to avoid cognitive fatigue, reconsidering proposed item difficulty levels, and reducing Likert scale to 4 levels. Rasch diagnostics also indicated favorable levels of instrument reliability and appropriate targeting of item abilities to student abilities for the majority of participants. A revised QI instrument is available for STEM researchers and educators

Surface-Enhanced Nitrate Photolysis on Ice

Heterogeneous nitrates photolysis is the trigger for many chemical processes occurring in the polar boundary layer and is widely believed to occur in a quasi-liquid layer (QLL) at the surface of ice. The dipole forbidden character of the electronic transition relevant to boundary layer atmospheric chemistry and the small photolysis/photoproducts quantum yields in ice (and in water) may confer a significant enhancement and interfacial specificity to this important photochemical reaction at the surface of ice. Using amorphous solid water films at cryogenic temperatures as models for the disordered interstitial air/ice interface within the snowpack suppresses the diffusive uptake kinetics thereby prolonging the residence time of nitrate anions at the surface of ice. This approach allows their slow heterogeneous photolysis kinetics to be studied providing the first direct evidence that nitrates adsorbed onto the first molecular layer at the surface of ice are photolyzed more effectively than those dissolved within the bulk. Vibrational spectroscopy allows the ~3-fold enhancement in photolysis rates to be correlated with the nitrates’ distorted intramolecular geometry thereby hinting at the role played by the greater chemical heterogeneity in their solvation environment at the surface of ice than in the bulk. A simple 1D kinetic model suggests 1-that a 3(6)-fold enhancement in photolysis rate for nitrates adsorbed onto the ice surface could increase the photochemical NO[subscript 2] emissions from a 5(8) nm thick photochemically active interfacial layer by 30%(60)%, and 2-that 25%(40%) of the NO[subscript 2] photochemical emissions to the snowpack interstitial air are released from the top-most molecularly thin surface layer on ice. These findings may provide a new paradigm for heterogeneous (photo)chemistry at temperatures below those required for a QLL to form at the ice surface

Juice from juice: Bringing solar energy education to the classroom

The Center for Chem. Innovation in Solar Fuels (CCI Solar) has developed several diverse outreach programs over the 10 years of its existence that satisfy the National Science Foundation's Broader Impacts requirements, including citizen science, informal science education, and teacher professional development. Started in 2008, Juice from Juice is a teacher professional development program where researchers from the Center put on workshops for local teachers to introduce them to solar energy expts. and curriculum that they can implement in their classrooms. The program was originally local to the Pasadena area centered on the CCI's headquarters at Caltech. Teachers from the Pasadena Unified School District and researchers at Caltech developed the expts. and curriculum together, along with assembling kits for teachers to take back to their classroom. After professional evaluation of the program and feedback from the National Science Foundation program officer, multiple changes were implemented that not only improved the quality of the local Juice from Juice workshops, but also allowed the program to expand across the country. Now as the sunset of the Center is on the horizon, CCI Solar is reflecting on the success and challenges of the Juice from Juice program and looking to permanently secure the future of this robust, popular program. Director of Education, Outreach and Diversity at CCI Solar, Michelle DeBoever, will walk through the development of the Juice from Juice program, its evaluation, revisions to the program, and its potential future with a third party partner as Center funding comes to a close. Hopefully the story of Juice from Juice can serve as a model for other outreach programs and offer insight to what works (and what doesn't) when developing a teacher professional development workshop and offering classroom expt. kits and curriculum

Renewable energy based catalytic CH4 conversion to fuels

Natural gas is envisioned as a primary source of hydrocarbons in the foreseeable future. With the abundance of shale gas, the main concerns have shifted from the limited hydrocarbon availability to the sustainable methods of CH4 conversion to fuels. This is necessitated by high costs of natural gas transportation in its native gaseous form. Conventional gas-to-liquid conversion technologies are capital and scale intensive and can hardly be envisioned in their current form to be cost efficient in the remote locations of the natural gas extraction sites. Solar energy can be utilized at the gas extraction site to perform catalytic CH4 conversion using electrons obtained via photovoltaics or directly with photons. We provide broader insight into the catalytic CH4 conversion methods that utilize renewable energy via photo(electro)catalytic processes, with particular focus on the catalytic materials used, reaction conditions and intermediates, as well as their selectivity. Based on the currently available scientific literature, we propose several hybrid catalytic CH4 conversion processes based on both conventional and renewable – photo(electro)chemical – catalysis