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This NSF ITEST project (Award # 2148429) at Illinois State University focuses on engaging students in four Chicago Public High Schools in an afterschool STEM program, SUPERCHARGE, where they experience hands on activities with renewable energy technologies and related sustainability-tied experiences. Between 10 and 20 students met weekly afterschool during the first year of implementation which was preceded by a planning year in which teachers provided feedback on activities and connections to the communities of the schools were developed. Four faculty were involved in the design of the project and activities and an additional group of undergraduate STEM majors were also involved in the design and pilot of all activities. Four goals frame this project and research. These are to learn how (1) high school students’ knowledge of STEM careers and STEM domains change across their participation; (2) the high school students improve their interest in STEM career attainment and their self-efficacy for career relevant skills; (3) the undergraduate STEM majors’ views about Communities of Learners of Underrepresented Discoverers develop across their participation; and (4) teachers’ knowledge of current STEM domains, skills, and careers change. To examine the impact of the programming on each stakeholder group, PEAR’s CIS-S and CIS-E surveys, interviews, activity surveys, and workshop surveys were used. Currently, the data from the first year of programming includes 21 pre-post student surveys and 10 surveys from the undergraduate designers and 9 surveys from the teachers in the program. At this time, statistical tests were not appropriate due to these small numbers, but future years will bolster these numbers, and we anticipate the ability to perform statistical tests as the data set grows. Therefore, we focus on a qualitative analysis of the surveys and interviews at this stage. 

The Energy Grid Card Game was designed for pre-college students (grades 6-12) to be played in an informal learning environment. The game explores the technical, environmental, and economic choices and challenges of using energy resources throughout our daily lives. Undergraduates at Illinois State University designed the activity as part of the NSF-funded SUPERCHARGE project, which seeks to improve access to STEM college and career pathways while making connections to engineering and sustainability-related problems that can be addressed in their communities. 

The following activities are examples from a unit of study that focuses on harnessing, using, and controlling energy. These activities were designed for pre-college learners in grades 6-12 in informal learning settings as part of the SUPERCHARGE project] by undergraduates at Illinois State University. The goal of the project is to promote interest in college and career pathways related to engineering, sustainability, and renewable energy technologies. 

Hybrid complexes incorporating synthetic Mn-porphyrins into an artificial four-helix bundle domain of bacterial reaction centers created a system to investigate new electron transfer pathways. The reactions were initiated by illumination of the bacterial reaction centers, whose primary photochemistry involves electron transfer from the bacteriochlorophyll dimer through a series of electron acceptors to the quinone electron acceptors. Porphyrins with diphenyl, dimesityl, or fluorinated substituents were synthesized containing either Mn or Zn. Electrochemical measurements revealed potentials for Mn(III)/Mn(II) transitions that are ~ 0.4 V higher for the fluorinated Mn-porphyrins than the diphenyl and dimesityl Mn-porphyrins. The synthetic porphyrins were introduced into the proteins by binding to a four-helix bundle domain that was genetically fused to the reaction center. Light excitation of the bacteriochlorophyll dimer of the reaction center resulted in new derivative signals, in the 400 to 450 nm region of light-minus-dark spectra, that are consistent with oxidation of the fluorinated Mn(II) porphyrins and reduction of the diphenyl and dimesityl Mn(III) porphyrins. These features recovered in the dark and were not observed in the Zn(II) porphyrins. The amplitudes of the signals were dependent upon the oxidation/reduction midpoint potentials of the bacteriochlorophyll dimer. These results are interpreted as photo-induced charge-separation processes resulting in redox changes of the Mn-porphyrins, demonstrating the utility of the hybrid artificial reaction center system to establish design guidelines for novel electron transfer reactions. 

We applied reaction microscopy to elucidate fast non-adiabatic dissociation dynamics of deuterated water molecules after direct photo-double ionization at 61 eV with synchrotron radiation. For the very rare D+ + O+ + D breakup channel, the particle momenta, angular, and energy distributions of electrons and ions, measured in coincidence, reveal distinct electronic dication states and their dissociation pathways via spin–orbit coupling and charge transfer at crossings and seams on the potential energy surfaces. Notably, we could distinguish between direct and fast sequential dissociation scenarios. For the latter case, our measurements reveal the geometry and orientation of the deuterated water molecule with respect to the polarization vector that leads to this rare 3-body molecular breakup channel. Aided by multi-reference configuration-interaction calculations, the dissociation dynamics could be traced on the relevant potential energy surfaces and particularly their crossings and seams. This approach also unraveled the ultrafast time scales governing these processes. 

Creation of a super-excited radical water cation results in a long-lived excited oxygen fragment that can act as a destructive carrier and initiate secondary reactions such as breakup of DNA strands – a key radiation damage mechanism.