SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4269-4
Self-assembled molecular interlayers (SAMs) are promising hole-selective contacts for high-efficiency organic solar cells (OSCs) due to their well-defined energy alignment and minimal parasitic absorption. However, their intrinsically limited mechanical robustness often leads to structural degradation and performance loss under mechanical deformation, restricting their application in flexible devices. Here, we report a nanoparticle-reinforced self-assembled composite interface that simultaneously enhances mechanical reliability and optoelectronic performance. Uniformly dispersed SiO2 nanoparticles are introduced as high-modulus reinforcing building blocks without disturbing molecular self-assembly. In contrast to NiOx nanoparticles, which suffer from aggregation and parasitic absorption, SiO2 nanoparticles exhibit excellent dispersion and optical transparency, enabling formation of a structurally compatible hybrid interface. Mechanistic studies reveal that SiO2 nanoparticles redistribute interfacial stress and form dynamic hydrogen-bond networks with phosphonic acid groups of 2PACz, providing efficient energy dissipation during cyclic deformation. Meanwhile, modulation of interfacial polarity extends the crystallization time window of the active layer, resulting in enhanced molecular ordering and improved charge transport. As a result, devices based on the SiO2/2PACz composite interface achieve a power conversion efficiency of 20.14% for rigid devices and 19.30% for flexible devices, placing the flexible devices among the highest-performing flexible OSCs reported to date, while retaining over 90% of their initial efficiency after repeated bending cycles. This work establishes a general strategy for overcoming the trade-off between electronic selectivity and mechanical robustness in ultrathin self-assembled molecular interfaces, providing design insights for high-performance flexible organic optoelectronics.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4378-6
Electrical stimulation (ES) is a powerful strategy to mimic endogenous bioelectricity and accelerate complex tissue regeneration, such as chronic wound healing. However, aligning external stimulation with native bioelectrical and biochemical signals for rapid and scarless tissue regeneration remains challenging. Here, we report a wireless bioelectronic dressing (E-dressing) that establishes stable bioelectronic interfaces and precisely modulates cellular physiological activities. Bioactive allylamine-functionalized gold clusterzymes (AM-AuNCs) with intrinsic superoxide dismutase-like activity were designed as functional modifiers to co-polymerize with acrylic acid (AA), forming conductive p(AA-AuNCs) hydrogels. AM-AuNCs impart the hydrogel with superior antioxidant activity, robust interfacial adhesion, and high conductivity, enabling rapid hemostasis, efficient electrical stimulation transmission, and precise fibroblast regulation. Combined with 1.00 V of electrical stimulation, the p(AA-AuNCs) hydrogel significantly promotes fibroblast proliferation, migration, and alignment by upregulating TGF-β, FGF-2, and EGF. Integrated with a biocompatible, flexible zinc-ion battery delivering sustained and tunable electrical signals for over 7 days, the E-dressing precisely guides collagen remodeling, inhibits myofibroblast activation, and maintains Col I/Col III balance, leading to a 5-fold acceleration of wound closure and a 65.5% reduction in scar formation. This multifunctional E-dressing represents a promising bioelectronic device for precise cellular regulation and multimodal regenerative therapy.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4106-8
Perovskite/organic tandem solar cells (PO-TSCs) have emerged as a compelling photovoltaic architecture to transcend the Shockley-Queisser limit of single-junction devices. By monolithically stacking a wide-bandgap (WBG) perovskite top cell and a narrow-bandgap (NBG) organic bottom cell, PO-TSCs enable broad spectral utilization and reduced thermalization loss, offering a viable pathway toward efficiencies beyond 30%. Their solution processability, compatibility with orthogonal solvents, and potential for lightweight, flexible, and semi-transparent modules further make them attractive for building integrated and portable electronics. However, the realization of high-performance PO-TSCs critically depends on precise carrier regulation across the entire multilayer stack, where inefficient charge transport, recombination losses, and interfacial bottlenecks often limit the overall power conversion efficiency (PCE) and stability. This review systematically examines the carrier-regulation strategies essential for advancing PO-TSCs, focusing on defect and phase-control in WBG perovskites, the design of optically transparent and electrically efficient interconnecting layers, and the enhancement of charge generation and collection in organic subcells. The integration of these approaches has recently enabled efficiencies exceeding 26%, demonstrating the rapid progress of the field. Ultimately, we conclude with an outlook on the remaining challenges in scalability, operational stability, and manufacturability, providing a roadmap for future research toward commercially viable tandem photovoltaics.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3571-y
Two-dimensional (2D) BiOBr has attracted considerable attention for optoelectronic applications, yet reported 2D BiOBr predominantly exhibits n-type conductivity. The absence of high-quality p-type 2D BiOBr impedes the development of complementary metal oxide semiconductor (CMOS) integrated circuits. This study reports the synthesis of large-scale, high-quality p-type 2D BiOBr single crystals via chemical potential modulation chemical vapor deposition (CPMCVD). By precisely modulating the oxygen chemical potential during growth, the conduction polarity of 2D BiOBr is controllably switched between p-type and n-type. Density functional theory calculations reveal that high oxygen chemical potential promotes bismuth vacancy formation, yielding p-type conductivity, whereas low oxygen chemical potential favors oxygen vacancies, resulting in n-type BiOBr. Field-effect transistors (FETs) fabricated from the p-type crystals exhibit a hole mobility of 26.28 cm2 V−1 s−1 and an on/off ratio exceeding 10^4. The n-type FETs demonstrate an electron mobility of 59.59 cm2 V−1 s−1, surpassing most reported n-type 2D FETs. This CPMCVD approach enables precise polarity control without extrinsic doping, offering a scalable route for integrating 2D BiOBr into CMOS technology.