Perovskites and graphene

Researchers from Taiwan's National Cheng Kung University and Chung Yuan Christian University have developed an interface-engineering strategy to overcome key efficiency bottlenecks in mesoporous perovskite solar cells by introducing APTS-functionalized reduced graphene oxide (APTS-rGO) into the electron transport structure.

The team focused on addressing persistent limitations associated with mesoporous TiO₂ (mp-TiO₂), which, despite its widespread use as an electron transport layer, suffers from interfacial resistance, energy level mismatch, and surface defect states that promote charge recombination. These effects suppress key photovoltaic parameters, including open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF).

Researchers at Jilin Jianzhu University, Harbin Institute of Technology, Nankai University and Sichuan University of Science & Engineering have developed a fully integrated wearable platform that combines flexible perovskite solar cells (FPSCs) with multifunctional graphene-based sensors, enabling simultaneous energy harvesting and real-time self-evaluation.

Wearable flexible solar cells have traditionally functioned solely as power sources, lacking the ability to monitor their own condition or provide feedback on performance degradation. This limitation makes it difficult to determine issues such as mechanical damage or optimal replacement timing. The team addressed this gap by integrating laser-induced graphene (LIG) sensors directly with a flexible perovskite solar cell on a single polyimide (PI) substrate, creating a monolithic system capable of both energy conversion and multi-parameter sensing.

Researchers from Bar-Ilan University, Israel; the Institute of Astronomy Space and Earth Science, India; Prabhat Kumar College, India; the University of Waterloo, Canada; the University of Goettingen, Germany; Sidho-Kanho-Birsha University, India; and the Indian Institute of Science, India have developed mini perovskite solar modules that combine competitive efficiency with over 1,300 hours of operational stability by engineering the buried hole-transport interface with reduced graphene oxide (r-GO). 

The work targets one of the main bottlenecks in perovskite photovoltaics - scaling from high-efficiency small cells to stable, larger-area modules - by systematically passivating the interface between a self-assembled monolayer (SAM)-based hole transport layer (HTL) and the perovskite absorber.

Researchers from India's CSIR-Central Scientific Instruments Organization have developed a predominantly dry, low-temperature fabrication process for flexible all-inorganic perovskite solar cells, combining material sustainability with high device performance.

The device structure - PET/ITO/rGO–SnO₂ (or rGO–TiO₂)/CsSn₁‑yGeᵧI₃/MoOₓ/Carbon - integrates lead-free CsSn₁‑yGeᵧI₃ absorbers and graphene-modified electron transport layers, enabling a power conversion efficiency of 19.2% with enhanced operational and mechanical stability. The architecture employs MoOₓ as a dopant-free hole transport layer with favorable energy-level alignment, while minimizing solvent use throughout fabrication.

GraphEnergyTech recently shared an update on its recent progress, funding goals, and strategic direction within the solar energy sector.

GraphEnergyTech’s selection for Japan’s Keihanna Global Acceleration Program (KGAP+) marks a significant milestone as the company’s graphene-enhanced carbon electrode technology aligns closely with Japan’s advanced perovskite solar cell ecosystem. A portfolio company of Frontier IP Group PLC (LSE:FIPP, FRA:8WT), GraphEnergyTech is currently raising a minimum of £3 million in a seed funding round. The capital will be used primarily to expand production capacity and accelerate R&D focused on silicon solar cells. However, CEO Dr. Thomas Baumeler noted that the company also has “a solution that fits particularly well with perovskite solar cells.”

Researchers from the University of Barcelona, Jaume I University, Slovak University of Technology and University of Valencia have engineered ultrasensitive photodetectors based on inkjet-printed nanocrystalline films of mixed-phase “raisin bread” CsPbBr₃/Cs₄PbBr₆ perovskite integrated onto graphene. By embedding photoactive CsPbBr₃ nanocrystals within a wider-bandgap Cs₄PbBr₆ matrix, the team creates a composite architecture that enhances charge confinement while simultaneously improving environmental stability relative to conventional perovskite films.

The raisin-bread morphology plays a central role in suppressing non-radiative recombination and mitigating degradation pathways that typically limit metal-halide perovskites in photodetector operation. In this configuration, the Cs₄PbBr₆ host passivates the surface of CsPbBr₃ nanodomains and acts as a protective scaffold, helping preserve optoelectronic properties over extended operation under ambient conditions. Coupled with solution-based inkjet deposition, this strategy demonstrates that complex phase-engineered perovskite microstructures can be reproducibly formed over large areas in a maskless, vacuum-free process, supporting low-cost, scalable manufacturing.

Researchers from Dongguan University of Technology have demonstrated a perovskite/graphene heterostructure that overcomes key challenges in metal-halide perovskite X-ray detectors, such as charge recombination caused by thick, defect-prone films. 

By combining CsPbBr₃ perovskite’s strong X-ray absorption and photophysical performance with graphene’s ultrahigh carrier mobility (> 10⁴ cm²·V⁻¹·s⁻¹), the heterostructure achieves efficient charge transport and reduced non-radiative losses. A MAPbCl₃ buffer layer at the perovskite/Si interface further alleviates lattice mismatch and enhances adhesion by 10×. 

Halocell and First Graphene have signed an exclusive license agreement that highlights a significant boost for perovskite solar cell (PSC) performance and commercialization. The new deal centers on graphene-enhanced carbon paste already proven to improve Halocell’s perovskite modules, particularly for indoor and lightweight applications.​

Graphene-enhanced carbon paste (L); paste layer on a perovskite solar cell (R). Image credit: First Graphene

Under the 12‑month exclusive License Agreement, First Graphene will manufacture, market and sell the graphene-enhanced carbon paste globally, while Halocell will receive a 10% royalty on sales and continue to use the material in its commercially available PSCs. This builds on an earlier Joint Development Agreement and a CRC-P Partners Agreement under which the partners optimized graphene loading, formulation and processing for PSC carbon pastes.

First Graphene has reported the addition of graphene to perovskite solar cells (PSC) can improve efficiency by 30% and reduce production costs by up to 80%.

The company has partnered with Halocell Energy and Queensland University of Technology to develop graphene-enhanced PSCs through the addition of its PureGRAPH novel functionalized graphene. A three-year AU$2.03 million grant under the federal government’s Co-operative Research Centers Projects (CRC-P) program is funding the research and development agreement, which commenced in 2023.

A research team from East China University of Science and Technology has unveiled a novel method to extend the lifespan of perovskite solar cells by developing an ultrathin protective layer for perovskite materials using graphene and a special transparent polymer. Experiments showed this "armor" doubles materials' stress resistance, reducing the expansion rate to 0.08 percent from 0.31 percent.

Perovskite materials expand by over 1 percent when exposed to light, the team noted, adding that they repeatedly expand and contract under sunlight, like an inflating and deflating balloon, causing the internal crystals to squeeze each other and generate destructive forces, ultimately leading to structural failure. Cells protected by the team's new "armor" maintained 97% efficiency after 3,670 hours, or about 153 days, of continuous operation under simulated real-world conditions of intense light and high temperatures, marking the longest-ever stable operation period for perovskite cells and providing feasibility for commercial use.