Luísa Andrade

Transparent conducting oxides and electron transport layers are central to optoelectronic devices, yet their interfacial electronic behavior remains strongly dependent on substrate chemistry, defect states, and surface potential alignment. Here, we compare ITO and FTO transparent electrodes coated with ZnO and TiO₂, combining ab initio simulations, surface potential mapping, Hall effect measurements, sheet resistance, microscopy, and optical spectroscopy. Density functional calculations show that both ITO and FTO behave as degenerately doped n-type transparent conducting oxides, but with distinct work functions, surface dipoles, and donor-state distributions, leading to different interfacial charge-transfer tendencies. ZnO- and TiO₂-coated substrates display markedly different temperature-dependent transport, including resistance hysteresis and carrier-type switching, with FTO-based heterojunctions showing more clearly defined transitions due to the greater thermal stability of FTO. Scanning Kelvin probe (SKP) measurements reveal that ZnO more effectively accepts electrons from ITO or FTO, whereas TiO₂ shows weaker electron accumulation and more resistive interfacial behavior. Optical measurements and HSE06-based simulations confirm that TiO₂ behaves as a wider-gap ultraviolet absorber, while ZnO exhibits a lower-energy absorption onset, with real spectra additionally shaped by substrate, thickness, scattering, and defect contributions. The results show that transparent conducting oxide substrates are active electronic participants, not passive supports, in ZnO- and TiO₂-based optoelectronic interfaces.

The performance of perovskite solar cells (PSCs) has increased markedly from 17.9% to 26.95% in less than a decade, rendering this technology increasingly competitive in the photovoltaic field. Among scalable deposition methods, the slot‐die coating technique stands out for its suitability in large‐area film deposition, offering perovskite film uniformity, reduced material waste, enhanced reproducibility, and compatibility with flexible substrates. This study focuses on optimizing slot‐die coating parameters for all active layers in inverted PSCs, namely the hole transport layer, perovskite absorber, and electron transport layer. The selected device architecture, PTAA/MAPbI ₃ /PCBM/BCP/Ag, is recognized for its superior air stability. The film morphology was analyzed using scanning electron microscopy and atomic force microscopy, while the crystallinity of the perovskite layer was assessed through X‐ray diffraction. The fabrication process for a 5 cm ² PSC device was refined using a design of experiments methodology. The champion cell, manufactured using slot‐die coating in ambient air conditions, reached a power conversion efficiency of 8.12% and maintained stable performance for over 800 h when stored in the dark under an inert atmosphere.

Perovskite solar cells (PSCs) have rapidly evolved into one of the most promising photovoltaic technologies, achieving power conversion efficiencies comparable to established silicon devices while offering unique advantages such as low weight, mechanical flexibility, and low-temperature, solution-based manufacturing. These attributes, combined with recently demonstrated tolerance to high-energy particle irradiation, position PSCs as compelling candidates for next-generation space power systems. This perspective work summarizes recent advances in PSC development for space environments, focusing on their behaviour under key stressors such as radiation (e.g., electrons, protons, gamma rays, and neutrons), ultraviolet exposure, extreme thermal cycling, and ultra-high vacuum. Progress in material design, device architecture, self-healing mechanisms, and encapsulation strategies is discussed, along with early in-orbit and suborbital demonstrations. Remaining challenges, including long-term stability, encapsulation reliability, large-area scalability, and the need for standardized space-qualification protocols, are also outlined. Indeed, PSCs represent a compelling opportunity for next-generation space photovoltaics, provided that targeted materials and engineering solutions address critical issues of encapsulation and durability under combined stressors to ensure reliable operation in harsh extraterrestrial conditions.

An ensemble of machine-learning algorithms that guides the prioritization of experimentally feasible, sustainable chalcogenide perovskites for next-generation photovoltaics is presented.

Perovskite solar cells (PSCs) hold promise for high-efficiency photovoltaic technology but face commercialization challenges due to scaling difficulties. A common approach for scaling PSCs involves creating perovskite solar modules (PSMs) with subcells connected in series, using P1, P2, and P3 laser scribing process to reduce interconnection losses. In this study, a standard nanosecond pulse UV laser was used to perform these scribes. Here we demonstrated that, by employing a single 45 µm laser line for each scribe, it can significantly reduce the dead area, resulting in exceptionally high geometric fill factors (GFFs). In inverted PSMs with active areas of 4.0 cm ² and 10.8 cm ² , it was reached GFFs of 99.3% and 98.8%, respectively. To the best of author’s knowledge, this work demonstrates the first successful use of a single nanosecond laser source for continuous P1-P2-P3 scribing, achieving a dead area as low as 0.7% in a 4 cm ² module.

Perovskite solar cells (PSCs) offer a viable alternative to silicon‐based technologies. Assessing their environmental performance is essential for a responsible development. This study compares the life cycle impacts of two PSC architectures, mesoporous n‐i‐p and inverted p‐i‐n, using the life cycle assessment methodology. The functional unit (FU) is a PSC with an active area of 2.88 cm². The life cycle inventory uses primary production data complemented with literature, the EcoInvent v3.9.1 database, and process modeling. Environmental impacts are evaluated using the ReCiPe 2016 method in SimaPro v9.5.0.1. Results indicate that producing mesoporous PSCs has a higher environmental impact than producing inverted PSCs, due to differences in material and energy consumption. Specifically, mesoporous PSCs require about 132 MJ/FU compared to 25 MJ/FU for inverted PSCs, leading to carbon footprints of 14.1 kg CO₂ eq./FU and 2.31 kg CO₂ eq./FU, respectively. For inverted PSCs, energy consumption dominates the environmental impacts, accounting for around 80% of the total impact, while for mesoporous PSCs, depending on the environmental category, both materials and energy can dominate. Results highlight that energy consumption is critical and could be significantly reduced by using fully renewable electricity and/or minimizing the presence of metal in the back‐contact.

Perovskite solar cells (PSCs) are the most rapidly advancing photovoltaic technology in terms of power conversion efficiency. An efficiency of 26.1% was achieved in a decade, which is on par with the efficiency of very mature silicon panels. However, PSC commercialisation is partly hindered by the difficulty of scaling these devices without efficiency loss, mostly due to the increasing sheet resistance of the transparent conductive layer substrates and the nonuniformity of the layers when deposited across large areas. Therefore, it is crucial for the commercialisation of PSCs to implement easily scalable deposition processes with low material waste and compatibility with roll-to-roll (R2R) processes to reduce manufacturing costs. Slot-die coating can meet all these requirements, allowing for great uniformity over large areas. The most recent developments in PSC upscaling using slot-die coating as the main deposition process, along with its extension to the R2R process, are reviewed, including a thorough discussion of the slot-die coating process and the theory behind its operating limits. In fact, R2R coating is a very promising strategy for PSC industrialisation, since all processing steps use low-cost materials and scalable processes at temperatures lower than 120 °C, allowing the cost-effective and high-throughput production of PSC devices.