Development of wide bandgap perovskites for next-generation low-cost CdTe tandem solar cells

Advancements in Photovoltaic Cell Materials: Silicon, Organic, and Perovskite Solar Cells

The evolution of photovoltaic cells is intrinsically linked to advancements in the materials from which they are fabricated. This review paper provides an in-depth analysis of the latest developments in silicon-based, organic, and perovskite solar cells, which are at the forefront of photovoltaic research. We scrutinize the unique characteristics, advantages, and limitations of each material class, emphasizing their contributions to efficiency, stability, and commercial viability. Silicon-based cells are explored for their enduring relevance and recent innovations in crystalline structures. Organic photovoltaic cells are examined for their flexibility and potential for low-cost production, while perovskites are highlighted for their remarkable efficiency gains and ease of fabrication. The paper also addresses the challenges of material stability, scalability, and environmental impact, offering a balanced perspective on the current state and future potential of these material technologies.

Cotton soot derived carbon nanoparticles for NiO supported processing temperature tuned ambient perovskite solar cells

The emergence of perovskite solar cells (PSCs) in a "catfish effect" of other conventional photovoltaic technologies with the massive growth of high-power conversion efficiency (PCE) has given a new direction to the entire solar energy field. Replacing traditional metal-based electrodes with carbon-based materials is one of the front-runners among many other investigations in this field due to its cost-effective processability and high stability. Carbon-based perovskite solar cells (c-PSCs) have shown great potential for the development of large scale photovoltaics. First of its kind, here we introduce a facile and cost-effective large scale carbon nanoparticles (CNPs) synthesis from mustard oil assisted cotton combustion for utilization in the mesoporous carbon-based perovskite solar cell (PSC). Also, we instigate two different directions of utilizing the carbon nanoparticles for a composite high temperature processed electrode (HTCN) and a low temperature processed electrode (LTCN) with detailed performance comparison. NiO/CNP composite thin film was used in high temperature processed electrodes, and for low temperature processed electrodes, separate NiO and CNP layers were deposited. The HTCN devices with the cell structure FTO/c-TiO2/m-TiO2/m-ZrO2/high-temperature NiO-CNP composite paste/infiltrated MAPI (CH3NH3PbI3) achieved a maximum PCE of 13.2%. In addition, high temperature based carbon devices had remarkable stability of ~ 1000 h (ambient condition), retaining almost 90% of their initial efficiency. In contrast, LTCN devices with configuration FTO/c-TiO2/m-TiO2/m-ZrO2/NiO/MAPI/low-temperature CNP had a PCE limit of 14.2%, maintaining ~ 72% of the initial PCE after 1000 h. Nevertheless, we believe this promising approach and the comparative study between the two different techniques would be highly suitable and adequate for the upcoming cutting-edge experimentations of PSC.

CdTe-Based Thin Film Solar Cells: Past, Present and Future

CdTe is a very robust and chemically stable material and for this reason its related solar cell thin film photovoltaic technology is now the only thin film technology in the first 10 top producers in the world. CdTe has an optimum band gap for the Schockley-Queisser limit and could deliver very high efficiencies as single junction device of more than 32%, with an open circuit voltage of 1 V and a short circuit current density exceeding 30 mA/cm2. CdTe solar cells were introduced at the beginning of the 70s and they have been studied and implemented particularly in the last 30 years. The strong improvement in efficiency in the last 5 years was obtained by a new redesign of the CdTe solar cell device reaching a single solar cell efficiency of 22.1% and a module efficiency of 19%. In this paper we describe the fabrication process following the history of the solar cell as it was developed in the early years up to the latest development and changes. Moreover the paper also presents future possible alternative absorbers and discusses the only apparently controversial environmental impacts of this fantastic technology.

Wide-Bandgap Metal Halide Perovskites for Tandem Solar Cells

Metal halide perovskite solar cells (PSCs) have become the most promising new-generation solar cell technology. To date, perovskites also represent the only polycrystalline thin-film absorber technology that has enabled >20% efficiency for wide-bandgap solar cells, making wide-bandgap PSCs uniquely positioned to enable high-efficiency and low-cost tandem solar cell technologies by coupling wide-bandgap perovskites with low-bandgap absorbers. In this Focus Review, we highlight recent research progress on developing wide-bandgap PSCs, including the key mechanisms associated with efficiency loss and instability as well as strategies for overcoming these challenges. We also discuss recent accomplishments and research trends on using wide-bandgap PSCs in perovskite-based tandem configurations, including perovskite/perovskite, perovskite/Si, perovskite/CIGS, and other emerging tandem technologies.

Comprehensive review of the recent advances in PV/T system with loop-pipe configuration and nanofluid

Solar photovoltaic/thermal technology has been widely utilized in building service area as it generates thermal and electrical energy simultaneously. In order to improve the photovoltaic/thermal system performance, nanofluids are employed as the thermal fluid owing to its high thermal conductivity. This paper summarizes the state-of-the-art of the photovoltaic/thermal systems with different loop-pipe configurations (including heat pipe, vacuum tube, roll-bond, heat exchanger, micro-channel, U-tube, triangular tube and heat mat) and nanoparticles (including Copper-oxide, Aluminium-oxide, Silicon carbide, Tribute, Magnesium-oxide, Cerium-oxide, Tungsten-oxide, Titanium-oxide, Zirconia-oxide, Graphene and Carbon). The influences of the critical parameters like nanoparticle optical and thermal properties, volume fraction, mass flux and mass flow rates, on the photovoltaic/thermal system performance are for the optimum energy efficiency. Furthermore, the structure and manufacturing of solar cells, micro-thermometry analysis of solar cells and recycling process of photovoltaic panels are explored. At the end, the standpoints, recommendations and potential future development on the solar photovoltaic/thermal system with various configurations and nanofluids are deliberated to overcome the barriers and challenges for the practical application. This study demonstrates that the advanced photovoltaic/thermal configuration could improve the system energy efficiency approximately 15%-30% in comparison with the conventional type whereas the nanofluid is able to boost the efficiency around 10%-20% compared to that with traditional working fluid.

Photon management to reduce energy loss in perovskite solar cells

Despite the rapid development of perovskite solar cells (PSCs) over the past few years, the conversion of solar energy into electricity is not efficient enough or cost-competitive yet. The principal energy loss in the conversion of solar energy to electricity fundamentally originates from the non-absorption of low-energy photons ascribed to Shockley-Queisser limits and thermalization losses of high-energy photons. Enhancing the light-harvesting efficiency of the perovskite photoactive layer by developing efficient photo management strategies with functional materials and arrays remains a long-standing challenge. Here, we briefly review the historical research trials and future research trends to overcome the fundamental loss mechanisms in PSCs, including upconversion, downconversion, scattering, tandem/graded structures, texturing, anti-reflection, and luminescent solar concentrators. We will deeply emphasize the availability and analyze the importance of a fine device structure, fluorescence efficiency, material proportion, and integration position for performance improvement. The unique energy level structure arising from the 4fn inner shell configuration of the trivalent rare-earth ions gives multifarious options for efficient light-harvesting by upconversion and downconversion. Tandem or graded PSCs by combining a series of subcells with varying bandgaps seek to rectify the spectral mismatch. Plasmonic nanostructures function as a secondary light source to augment the light-trapping within the perovskite layer and carrier transporting layer, enabling enhanced carrier generation. Texturing the interior using controllable micro/nanoarrays can realize light-matter interactions. Anti-reflective coatings on the top glass cover of the PSCs bring about better transmission and glare reduction. Photon concentration through perovskite-based luminescent solar concentrators offers a path to increase efficiency at reduced cost and plays a role in building-integrated photovoltaics. Distinct from other published reviews, we here systematically and hierarchically present all of the photon management strategies in PSCs by presenting the theoretical possibilities and summarizing the experimental results, expecting to inspire future research in the field of photovoltaics, phototransistors, photoelectrochemical sensors, photocatalysis, and especially light-emitting diodes. We further assess the overall possibilities of the strategies based on ultimate efficiency prospects, material requirements, and developmental outlook.

Performance of WO3-Incorporated Carbon Electrodes for Ambient Mesoscopic Perovskite Solar Cells

The stability of perovskite solar cells (PSC) is often compromised by the organic hole transport materials (HTMs). We report here the effect of WO₃ as an inorganic HTM for carbon electrodes for improved stability in PSCs, which are made under ambient conditions. Sequential fabrication of the PSC was performed under ambient conditions with mesoporous TiO₂/Al₂O₃/CH₃NH₃PbI₃ layers, and, on the top of these layers, the WO₃ nanoparticle-embedded carbon electrode was used. Different concentrations of WO₃ nanoparticles as HTM incorporated in carbon counter electrodes were tested, which varied the stability of the cell under ambient conditions. The addition of 7.5% WO₃ (by volume) led to a maximum power conversion efficiency of 10.5%, whereas the stability of the cells under ambient condition was ∼350 h, maintaining ∼80% of the initial efficiency under light illumination. At the same time, the higher WO₃ concentration exhibited an efficiency of 9.5%, which was stable up to ∼500 h with a loss of only ∼15% of the initial efficiency under normal atmospheric conditions and light illumination. This work demonstrates an effective way to improve the stability of carbon-based perovskite solar cells without affecting the efficiency for future applications.