THE GOAL OF THIS 18-MONTH PROJECT IS TO ADVANCE ESTABLISHED LOW-COST, SCALABLE, IN-LINE ELECTROCHEMICAL DEFECT QUANTIFICATION PLATFORMS THAT CAN BE SHARED WITH THE BROADER RESEARCH COMMUNITY TO ELUCIDATE THE IMPACTS OF LIGHT- AND THERMAL-INDUCED HALIDE MIGRATION AT BURIED INTERFACES THAT CONTRIBUTE TO DECREASED STABILITY OF HIGH-PERFORMING, PRINTABLE PHOTOVOLTAICS USING LEAD HALIDE PEROVSKITES. IN OBJECTIVE 1, WE WILL DEVELOP A WAVELENGTH-DEPENDENT AND TEMPERATURE-DEPENDENT PROTOTYPE TECHNIQUE THAT WILL BE USED FOR TIME-DEPENDENT FAILURE ANALYSIS BY TRACKING DEFECT CONCENTRATIONS AND ENERGETICS ON MA-FREE LEAD HALIDE PEROVSKITES FILMS DEPOSITED INTERNALLY AS PEROVSKITE/CHARGE TRANSPORT LAYER (CTL)/TRANSPARENT CONDUCTING OXIDE (TCO) HALF-STRUCTURES (MILESTONE 1.3). BENCHMARKING OF THE PROTOTYPE WILL BE DONE BY TESTING HALF-STACKS PROVIDED BY AT LEAST ONE EXTERNAL PARTNER (MILESTONE 1.4) AND REPORTING TO THE COMMUNITY. IN OBJECTIVE 2, WE AIM TO DEVELOP A FAILURE ANALYSIS APPROACH FOR PEROVSKITE SOLAR CELLS TO DEFINE THE PROTECTIVE NATURE OF TOP CONTACTS BY DEGRADING A COMPLETE DEVICE STACK AND REMOVING ITS TOP SECTION TO MEASURE DEFECT CONCENTRATIONS AS A FUNCTION OF EXPOSURE TIME IN AN ENVIRONMENTAL CHAMBER AND COMPARE TO STANDARD MAXIMUM POWER POINT TRACKING (MILESTONE 2). RUNNING CONCURRENTLY WITH OBJECTIVE 1 AND 2, OBJECTIVE 3 WILL TARGET THE RECRUITMENT AND INCLUSION OF EARLY CAREER RESEARCHERS (I.E., TWO UNDERGRADUATE STUDENTS) TO UNDERTAKE INDIVIDUAL COMPONENTS OF THE RESEARCH PROGRAM (MILESTONE 3.1) AND DEVELOP AN INTEREST AND MATRICULATION INTO THE GRADUATE STUDENT COMMUNITY. THE FINAL GOAL IS TO DELIVER A HARDWARE AND SOFTWARE PLATFORM USING COMMERCIALLY AVAILABLE PARTS, WHICH ONCE ASSEMBLED, WOULD ALLOW FOR AN ELECTROCHEMICAL APPROACH THAT FUNCTIONS AS A RELIABLE, LOW-COST, OPERANDO ACCELERATED CONTROL SYSTEM TO MEASURE STABILITY AND DURABILITY OF SEMICONDUCTOR FILMS USED IN A BROAD ARRAY OF OPTOELECTRONIC STACKS AS A FUNCTION OF WAVELENGTH AND TEMPERATURE. SUCH A PLATFORM WILL ALLOW US TO ASSESS DEVICE DEGRADATION UNDER EXTERNAL STRESS CONDITIONS AND TEST OUR CENTRAL HYPOTHESIS: BLUE LIGHT INDUCES HALIDE DISSOCIATION FROM THE PEROVSKITE LATTICE AND CONTRIBUTES TO INSTABILITIES DUE TO MOBILE HALIDE SPECIES; THE RATE OF DEFECT FORMATION AND EVOLUTION IS POSTULATED TO INCREASE WITH INCREASING TEMPERATURE. THE FIRST END OF PROJECT DELIVERABLE WILL BE THE SUBMISSION OF A MANUSCRIPT DETAILING THE SYSTEM COMPONENTS AND SCIENTIFIC DEMONSTRATION OF RELEVANT WAVELENGTHS AND TEMPERATURES CONTRIBUTING TO HALF-STACK DEGRADATION (EOP-A). THE ELECTROCHEMICAL APPROACH FOR HALF-STACKS WILL BE BENCHMARKED TO DEVICE LIFETIMES TO DEMONSTRATE FEASIBILITY AS A NEW ACCELERATED STABILITY PROTOCOL FOR THE BROADER METAL HALIDE PEROVSKITE SOLAR CELL COMMUNITY (EOP-B), TOWARDS INCREASED DEVICE LIFETIMES TO COMMERCIAL LEVEL REQUIREMENTS. TWO UNDERGRADUATE STUDENTS FROM UNDERREPRESENTED MINORITIES IN STEM HAVE COMPLETED AND PRESENTED ON INDIVIDUAL RESEARCH PROJECTS THAT INCLUDE THE DEVELOPMENT OF THE NEW SPECTROELECTROCHEMICAL SYSTEM (EOP-C).