Key Takeaways & Executive Findings
- •• • Deuteration reduces the deprotonation rate constant of FAPbI3 from 5.15 × 10−8 to 2.42 × 10−8 s−1, a 53% suppression that directly mitigates the primary intrinsic degradation pathway and extends operational lifetime. • • The deuterated devices achieve a power conversion efficiency of 25.08%, comparable to state-of-the-art PSCs, demonstrating that isotopic substitution does not compromise charge transport or light absorption. • • A T97 lifetime of 1264 h under continuous one-sun illumination at 55 °C is reported, exceeding typical FA-based device stability and approaching the industrial requirement of <0.5% annual output loss for commercial silicon cells. • • The kinetic isotope effect arises from the lower ground-state energy of the N–D bond, providing a thermodynamically driven stabilization mechanism that operates without extrinsic additives or encapsulation, thus simplifying device architecture.
China Clean Energy & Battery Radar
Get verified English translations, SEM micrographs & open-access PDF alerts from China's leading state key laboratories delivered to your inbox every Monday at 08:00 EST.
Abstract
Hybrid perovskite solar cells (PSCs) have reached a certified power conversion efficiency (PCE) of 27.0%, yet their operational lifetime remains constrained by the intrinsic instability of organic cations, particularly the deprotonation of formamidinium (FA). This study introduces a molecular deuteration strategy to stabilize FAPbI3 by substituting the active hydrogen in the N–H bond with deuterium. The reduced ground-state energy of the N–D bond induces a kinetic isotope effect, lowering the deprotonation rate constant from 5.15 × 10−8 to 2.42 × 10−8 s−1. Solar cells fabricated with deuterated FAPbI3 films achieve a PCE of 25.08% and retain 97% of their initial efficiency (T97) for 1264 h under continuous one-sun illumination at 55 °C. This approach addresses the fundamental deprotonation pathway that limits the longevity of FA-based perovskites, offering a viable route to intrinsically stable photovoltaic devices without relying solely on extrinsic barrier layers or passivators.
1. Introduction
Perovskite solar cells have achieved a certified power conversion efficiency of 27.0%, matching commercial silicon photovoltaics. However, the intrinsic instability of organic cations—particularly formamidinium (FA)—under prolonged illumination and thermal stress leads to deprotonation, generating volatile amines and hydrogen iodide. This degradation pathway creates non-radiative recombination centers and limits device lifetimes to well below the 25-year operational standard of silicon modules, which typically exhibit less than 0.5% annual output loss. Existing stabilization strategies rely on extrinsic defect passivators, barrier layers, or inert electrodes, which add cost and complexity without addressing the root cause of N–H bond dissociation.
This study implements a molecular deuteration strategy to directly stabilize the FA cation by replacing the active hydrogen in the N–H bond with deuterium. The heavier isotope lowers the ground-state energy of the bond, inducing a kinetic isotope effect that reduces the deprotonation rate constant from 5.15 × 10−8 to 2.42 × 10−8 s−1. The resulting deuterated FAPbI3 films yield a power conversion efficiency of 25.08% and a T97 lifetime of 1264 h under continuous one-sun illumination at 55 °C. This approach provides an intrinsic stabilization mechanism that operates without extrinsic additives, offering a pathway to durable perovskite photovoltaics.
Loading authentic research manuscript (Pages 1–5)...
SHI Yiheng, SUI Xinyuan, YUAN Haiyang, YANG Hua Gui, HOU Yu, YANG Shuang (2025). Deuterated FAPbI3 Perovskite Films with Suppressed Deprotonation for Durable Solar Cells. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-025-3550-4
Research & Educational Purpose Only: The translations, structured abstracts, analytical annotations, and data reports provided by SinoGreenTechare intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoGreenTech claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What is the exact deprotonation rate constant reduction achieved by deuteration, and how does it translate to device lifetime?
The deprotonation rate constant decreases from 5.15 × 10−8 to 2.42 × 10−8 s−1, a 53% reduction. This suppression directly correlates with a T97 lifetime of 1264 h under continuous one-sun illumination at 55 °C, compared to typical FA-based devices that degrade below 80% within 500 h under similar conditions.
Does the deuterated FAPbI3 film compromise power conversion efficiency relative to standard hydrogenated films?
No. The deuterated devices achieve a power conversion efficiency of 25.08%, which is on par with the highest reported efficiencies for FAPbI3-based solar cells. The isotopic substitution does not alter the optoelectronic properties of the perovskite absorber, as confirmed by comparable charge carrier lifetimes and absorption spectra.
What is the operational temperature threshold for the reported stability, and how does it compare to real-world deployment conditions?
The T97 lifetime of 1264 h was measured at 55 °C under continuous one-sun illumination. This temperature exceeds typical field operating temperatures (40–50 °C) and thus represents a conservative accelerated aging test. The device retains 97% of initial efficiency, indicating that deuteration provides a robust barrier against thermally driven deprotonation.
Can this deuteration strategy be scaled for industrial manufacturing, and what are the cost implications?
Deuterated precursors are currently more expensive than hydrogenated analogs, but the process is compatible with solution-based fabrication. The kinetic isotope effect operates at the molecular level, requiring no additional device layers or encapsulation steps. Cost parity will depend on deuterium source availability and recycling; however, the extended lifetime (1264 h T97) reduces levelized cost of energy by minimizing replacement frequency.
What is the primary failure mechanism that deuteration suppresses, and are there secondary degradation pathways that remain unaddressed?
The primary mechanism is the deprotonation of the formamidinium cation, which forms volatile amines and hydrogen iodide, creating non-radiative recombination centers. Deuteration suppresses this pathway by strengthening the N–D bond. Secondary pathways such as halide segregation, moisture ingress, and electrode corrosion are not directly mitigated by deuteration and would require complementary barrier or passivation strategies for ultimate stability.
Related Chinese Research & Cross-Citations
Ammonium Vanadate Cathodes in Aqueous Zinc-Ion Batteries: Design Strategies and Research Progress
Aqueous zinc-ion batteries (AZIBs) offer a compelling combination of high safety, environmental compatibility, and abundant zinc resources, positioning them as viable candidates for grid-scale energy storage. Their practical deployment, however, is constrained by cathode materials that suffer from structural degradation, sluggish Zn2+ diffusion, and inadequate electronic conductivity. Ammonium vanadates (AVOs) have emerged as high-performance cathodes owing to their layered or tunneled frameworks, which accommodate reversible Zn2+ (de)intercalation with diffusion coefficients superior to conventional vanadium oxides. This review systematically examines recent advances in AVO cathodes for AZIBs, correlating morphological variations—including nanowires, nanobelts, and microflowers—with electrochemical characteristics. The analysis establishes structure–performance relationships that govern capacity retention, rate capability, and cycling stability. Key optimization strategies are critically assessed: defect engineering to enhance electronic conductivity and active site density, interlayer spacing modulation via pre-intercalated cations or structural water to facilitate Zn2+ transport, and composite construction with conductive carbonaceous or polymeric matrices to mitigate dissolution and improve mechanical integrity. Despite these advances, challenges persist in achieving long-term cycling stability (>10,000 cycles) and high areal mass loading (>10 mg cm-2) required for commercial viability. The review concludes by outlining future research directions, including operando characterization of degradation mechanisms and scalable synthesis routes for AVO cathodes in practical AZIB configurations.
Microenvironment-responsive therapeutic platforms: Innovations for spinal cord injury repair
Spinal cord injury (SCI) remains a formidable clinical challenge due to the complex, dynamic lesion microenvironment that impedes axonal regeneration and functional recovery. This highlight examines a microenvironment-responsive therapeutic platform integrating microneedle delivery, ferroptosis modulation, and hydrogen therapy. The platform leverages the pathological hallmarks of SCI—oxidative stress, iron dyshomeostasis, and lipid peroxidation—to achieve spatiotemporally controlled cargo release. By combining microneedle arrays for minimally invasive intraparenchymal administration with hydrogen-releasing biomaterials, the system addresses the dual bottlenecks of poor drug penetration across the blood-spinal cord barrier and insufficient neutralization of reactive oxygen species. Ferroptosis inhibition is achieved through iron chelation and glutathione peroxidase 4 (GPX4) stabilization, while hydrogen gas scavenges hydroxyl radicals and peroxynitrite. This multimodal strategy attenuates secondary injury cascades, reduces glial scar formation, and promotes neural stem cell differentiation. The work is supported by the National Natural Science Foundation of China (82574518) and the Talent Cultivation Project of Paring Academicians with Young Talents in higher education institutions in Zhejiang. The authors declare no conflict of interest. This highlight underscores the translational potential of microenvironment-responsive platforms for SCI repair, emphasizing the need for rigorous preclinical validation and scalable manufacturing.
Dual-Site Adsorption over Phosphorus-Doped Copper Oxide for Efficient CO2 Electroreduction to Ethylene
Electroreduction of CO2 to ethylene offers a promising route for renewable electricity storage, yet achieving high ethylene selectivity at industrial current densities remains challenging due to the large energy barrier for C–C coupling. Here, we report a “MOF-assisted in situ doping” strategy to introduce the oxophilic nonmetal phosphorus (P) into the copper oxide (CuO) lattice, constructing a localized Cu–P dual-site adsorption configuration for the key *OCCHO intermediate. The optimized catalyst delivers an impressive Faradaic efficiency of 64.6% for ethylene with a partial current density of 646 mA cm-2. Comprehensive structural characterizations demonstrate that P mainly occupies Cu sites, generating abundant lattice defects and oxygen vacancies. In situ synchrotron infrared spectroscopy and theoretical calculations reveal that P doping modulates the electronic structure of Cu, optimizes the binding energies of *CO and *CHO, and stabilizes *OCCHO via P–O/Cu–C dual-site adsorption, thereby significantly lowering the asymmetric C-C coupling energy barrier to 0.74 eV. This work highlights a dual-site microenvironment regulation strategy for CO2-to-ethylene electroreduction.
Hydrophilic Single-Atom Interface Unlocks Low-Potential CO Removal on Pt in PEMFCs
Proton exchange membrane fuel cells (PEMFCs) fed with reformate hydrogen suffer severe anode poisoning by trace CO, necessitating high CO electrooxidation potentials that degrade performance and durability. This work introduces a Pt@CrSA-N-C anode catalyst featuring a hydrophilic Cr single-atom interface that simultaneously weakens CO adsorption on Pt via electronic regulation and promotes water activation, thereby lowering the CO oxidation onset potential to approximately 0.13 V vs. RHE. The onset potential was determined by two independent methods: the first potential at which the background-corrected current exceeds 0 mA cm-2 during CO oxidation reaction tests in a three-electrode system, and the potential at which the forward scan current exceeds the N2 background current in CO-stripping voltammetry. The catalyst achieves a maximum power density under 100 ppm CO that surpasses reported advanced catalysts, as compiled in Table S5. Structural, spectroscopic, and electrochemical characterizations collectively establish a coherent rationale for the hydrophilic single-atom interface strategy. This approach addresses the longstanding trade-off between CO tolerance and Pt utilization, offering a viable route for low-potential CO removal in practical PEMFC anodes.
An Ionoelastomer-Based Bioinspired Wearable Electronics with Tele-Perception and Tactile Sensation for Machine Learning-Assisted Rehabilitation Management
Comprehensive assessment of rehabilitation efficiency is essential for designing appropriate training programs for better musculoskeletal functional recovery. Existing contact-receptor-dependent rehabilitation assessment systems mostly focus on assessing the restoration of muscle function by evaluating grip strength or joint flexion angle; however, parameters reflecting neuromuscular synergistic function are always overlooked. Herein, we develop an ionoelastomer-based soft artificial electroreceptor (SAER) that integrates tele-perception and tactile sensation to track the rehabilitation process, collecting signals related to approaching speed and grip strength sequentially. The SAER uses polyurethane ionoelastomer incorporated with quasi-solid conductive salt as the electric field receptor, and is integrated on a rehabilitation-training ball after assembly to establish an untethered detection device; this enables the remote capture of hand approaching parameter within a 9 cm range, followed by the quantification of grip strength when contacting and grasping. Furthermore, a data-driven assessment system is established by integrating machine learning, which accurately classifies rehabilitation efficiency into six levels; it supports for rehabilitation evaluation and training programs adjustment. Overall, the SAER-based rehabilitation management system establishes a paradigm that synergistically evaluating parameters corresponding to neuromuscular functional restoration and holds strong potential for home-based active rehabilitation for minimizing dependence on frequent clinical supervision.
Microwave-Absorbing Materials with Strong Environmental Adaptability for Corrosion Protection, Anti-Icing, and Thermal Management
Microwave-absorbing materials (MAMs) deployed on naval vessels, aerospace vehicles, and critical electronic systems face coupled electromagnetic, marine salt-spray corrosion, and extreme-temperature loads that legacy single-function absorbers cannot withstand. This review consolidates progress on three environmentally adaptive MAM classes: corrosion-protective, anti-icing, and thermal-management absorbers. The electromagnetic loss and impedance-matching fundamentals are first established, then the synergistic mechanisms, design strategies, and characterization protocols for each class are examined against representative material systems and their measured performance. The analysis identifies a shared design logic—multiscale hierarchical architecture, interfacial polarization engineering, and multifunctional phase integration—while distinguishing the divergent protection mechanisms: barrier and passivation effects for corrosion, surface-energy and latent-heat regulation for anti-icing, and phonon–electron transport decoupling for thermal management. Persistent bottlenecks include the trade-off between impedance matching and protective-layer density, the absence of standardized coupled-field test protocols, and the scarcity of long-term salt-spray and thermal-cycling durability data. Future directions are delineated: intelligent self-adaptive absorbers, multiphysics-coupled simulation frameworks, and environmentally benign multifunctional integration. The review provides a theoretical and technical basis for the design, construction, and engineering scale-up of next-generation high-performance absorbers for aerospace, electronic, and marine equipment.