Optoelectronic devices – including a wide variety of solar cells, smart windows, light emitting diodes, but also photoelectrochemical cells for solar-driven fuel generation – have become increasingly important in our society. These devices are also driving important innovations in materials and device architectures to enable multiple functionalities. In these optoelectronic devices, contacts and interfaces between two adjacent layers are taking a dominant role in their performance. Indeed, for many of these applications, modern contacts increasingly need to fulfill multiple electrical functions such as surface passivation, carrier collection/injection, lateral conductivity, and effective contact to the outer device terminals, while being as broadband transparent as possible or exhibiting anti-reflective properties. Additional constraints may be present such as processing compatibility, overall device stability and reliability, and use of abundant and non-toxic materials. Overall, material design aided by computational and machine learning methods, precision synthesis, the use of hybrid organic-inorganic materials, interfacial engineering and smart integration of contacts in these devices will open the way to new functionality and improved efficiency. Together with contact material innovation, novel characterization methods to elucidate the role of the interfaces in device performance will be required to design of the next generation of optoelectronic devices. The goal of this symposium is to continue the dialogue in a multidisciplinary community of organic and inorganic material and device scientists, physicists, chemists, material modeling and prediction researchers working on optoelectronic materials, interface characterization and devices. We will discuss the current and future needs in contacting materials and interfaces, including those used in high-efficiency solar cells based on hybrid halide perovskites, silicon, organic, thin-film and III-V materials.

atomic layer deposition chemical composition electronic structure extended x-ray absorption fine structure (EXAFS) microstructure scanning transmission electron microscopy (STEM) spectroscopy surface chemistry x-ray diffraction (XRD) x-ray photoelectron spectroscopy (XPS)