Summary (goals and expected results):

  Concrete is the main material used for building civil infrastructure, so buildings offer margin for lowering their global sustainability impacts. Buildings sustainability can be addressed by innovations in the construction materials. We aim to use emerging binder; the geopolymer (GP) paste and functionalise it in conducting and/or transparent configuration, much like the transparent conducting oxides (TCO) materials, to research the possibility of integrating such materials with solar cells (SC).

  TCO are important for lateral current transport in many optoelectronic systems such as displays, touchscreens and SC. They are necessary in advanced SC with passivating contacts having in mind increasing importance in the quest for highest device efficiencies and therefore require a better understanding of interactions between the TCO and the passivation layers on which they are deposited. Common deposition methods are found to damage the passivation because of ion bombardment, where this project aim is to avoid or mitigate the damage to the layers by the use of softer deposition methods (chemical, spark ablation, etc.), or annealing, or hydrogenation, but still provide conductivity and transparency.

  In the 3^rd generation of SC, only charge transfer oxides (CTO) have been applied in nanostructured configuration. This project aims to investigate the benefits of such morphology in TCO layers, where nano-structuring was hardly employed, to allow better understanding of interactions between the nanostructured surfaces and adjacent layers. The aim is to expand the knowledge on interfacing of nanostructured TCO & CTO layers, to investigate their stability to atmosphere conditions. Namely, further interfacing, i.e. the issues in assembly of the layers into operative SC contribute to mayor challenges of the last-generation of energy-harvesting technology. SC will comprise following photo-absorbing layers: 1) silicon heterojunction (aim: upgrade periphery, thus stability/efficiency increase), 2) bulk-heterojunction hybrid-organic (aim: novel synthesis, thus tailoring of stability and absorption spectra) and 3) photoactive perovskite (aim: try co-absorbing, thus stability advancements).

  On behalf of a GP polymerisation engineering knowledge and SC layer interfacing findings we aim an attempt to incorporate GP in SC, as a proof-of-concept.

  Abovementioned course of investigation requires very broad spectra of advanced characterisation; many not available or up to date in Croatia. Yet Leaders established international collaboration pathway to allow access to, and utilisation of advanced equipment. Aim is also to develop new technique. Project maximise inclusion of Early Stage Researchers (ESR), where special attention will be devoted to their education via promoting the importance of international mobility and collaboration, to open doors for development of their inclusive way of thinking, personal growth, and solidifying of research network and Group impact.

  Aim is to broadly disseminate results findings, resulting in increased international visibility of research Group, Institutions involved and Funding body.

  The project deals with actual and popular scientific and industrial topics, with lucrative financial background just waiting for novel innovative solutions. The results may be applicable in a broad Technology Readiness Level (TRL), where opportunities may be found from fundamental research, over technology development, to prototyping, piloting and scale-up. Therefore, a reach-out to industrial stakeholders is a follow-up aim of the project.

Results

The project successfully conducted scientific research on the preparation and interconnection of nanostructured CTL and TCL layers. The project significantly expanded the state of knowledge in the context of SCs, but also in the broader context of devices for the preparation, conversion and storage of energy. Based on the above, it can be said that the project was particularly successful in terms of the application of researched materials and the networking of scientists. During the project, the head of the Group employed 7 doctoral students and 3 postdoctoral students from various project sources, and ~20 master and graduate theses were prepared. The leader also established the Laboratory for Thin Films at the Faculty of Chemical Engineering and Technology. The results of the project made it possible to obtain >5 projects, with actual 3 applications for HORIZON calls. The results were disseminated in over 50 scientific papers with international peer review, of which ~30 papers were cited in Q1 Current Contents journals, and at about 100 international scientific meetings, of which about 10 were plenary/invited presentations.