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Verified CAS / Academic Author4 Decoded Studies

Prof. GAO Feng

School of Materials Science and Engineering, Xi'an Jiaotong University

Co-Affiliations:Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, Shaanxi Normal UniversityZhejiang University

Research Publications & English Decoded Briefs

Showing 4 publications
SCIENCE CHINA Materials2026DOI: 10.1007/s40843-025-3727-0

Multilevel Encapsulation-Engineered Ultra-Stable Flexible Scintillator Films for High-Resolution X-ray Imaging

Lead halide perovskites are promising scintillators for X-ray imaging due to high X-ray absorption efficiency, excellent luminescence, and facile synthesis. However, their ionic nature challenges simultaneous high photoluminescence efficiency and environmental robustness. This work introduces a multilevel encapsulation strategy: CsPbBr3 quantum dots (QDs) are sequentially coated with Cs4PbBr6, SiO2, and polydimethylsiloxane (PDMS). Cs4PbBr6 passivates surface defects, while SiO2 and PDMS provide barriers against moisture, heat, and radiation. The resulting CsPbBr3@Cs4PbBr6/SiO2/PDMS flexible films exhibit a photoluminescence quantum yield (PLQY) of 85%, outstanding mechanical flexibility, and durability under stretching, bending, and compressing. Films retain emission stability under elevated temperatures, prolonged X-ray irradiation, and extended water immersion. X-ray imaging demonstrates spatial resolution of 12 lp/mm, enabling distortion-free imaging of curved objects; superior water resistance allows long-term underwater imaging. This work highlights hierarchical encapsulation in balancing luminescence efficiency and stability, offering a pathway toward practical flexible perovskite scintillators.

SCIENCE CHINA Materials2026DOI: 10.1007/s40843-025-3692-9

Lighting the Way: Precision Doping in Organic Semiconductors

Doping is essential for modulating semiconductor conductivity, forming p–n junctions, and reducing contact resistance. However, organic semiconductors (OSCs) face challenges in achieving precise regional doping due to uncontrollable dopant diffusion and poor process compatibility. This highlight discusses a breakthrough light-triggered strategy for spatially controlled n-type doping in OSCs, developed by Pei's Group. The method employs inert photoactivable dopants (iPADs) that are thermally stable but undergo rapid 6π-electrocyclization upon UV irradiation, transforming into potent n-dopants (PADs). These PADs irreversibly dope n-type OSCs via hydride transfer. With a high activation barrier (>28 kcal mol−1), the reaction is thermally suppressed even at 120°C, enabling orthogonal control: doping occurs only where and when light is applied. This approach achieves down to 1 μm spatial resolution, far surpassing physical masking methods. The method's universality accommodates diverse n-type OSCs (LUMO: −3.7 to −4.7 eV) with conductivity enhancements up to nine orders of magnitude (exceeding 30 S cm−1 in some systems). Doping levels, conductivity, and Fermi energy are tunable via UV dose and dopant concentration. The doped regions exhibit robust stability and withstand subsequent thermal processing, aligning with large-scale and flexible manufacturing. In organic field-effect transistors, precise spatial doping significantly enhances carrier mobility, reduces contact resistance to one-sixth of its original value, and effectively lowers surface trap density, providing critical support for device miniaturization and high-density integration.

SCIENCE CHINA Materials2026DOI: 10.1007/s40843-026-4072-3

Record Efficiency of 20.01% in HTM-Free Carbon-Based CsPbI3 Perovskite Solar Cells Achieved by TEPM Multifunctional Additive

All-inorganic, hole-transport-material-free (HTM-free), carbon-based perovskite solar cells (C-PSCs) have attracted significant attention due to their exceptional stability and low cost. However, their performance and commercial potential are constrained by poor interfacial contact, insufficient crystallinity, and energy level misalignment. In this work, we address these challenges via a molecular engineering strategy by introducing tetrakis(4-ethynylphenyl)methane (TEPM) as a multifunctional additive. The alkynyl moiety (C≡C) in TEPM coordinates with Pb2+ ions in perovskite precursors, synergistically slowing crystallization kinetics to regulate crystal growth and passivate deep-level defects. Consequently, CsPbI3 films exhibit larger grain sizes, improved crystallinity, and lower defect densities. Devices modified with TEPM achieved a record power conversion efficiency (PCE) of 20.01% (certified 19.58%). Additionally, unencapsulated devices retained 87.6% of their initial efficiency after 1080 h under ambient conditions (25 °C, 30% relative humidity), and maintained 94.0% of their initial efficiency after 730 h of continuous AM 1.5G illumination in air. This work sets a new efficiency benchmark for inorganic HTM-free C-PSCs and provides a versatile molecular engineering strategy for developing high-performance, stable perovskite photovoltaics.

SCIENCE CHINA Materials2025DOI: 10.1007/s40843-025-3479-9

Functional Antifouling Hydrogel Surface Engineering: Insight into Mechanisms, Interfacial Regulation and Marine Protection

Marine biofouling, the attachment and accumulation of marine organisms on submerged anthropogenic structures, imposes substantial operational and environmental burdens on shipping, offshore engineering, and marine ecosystems. Traditional antifouling strategies, including mechanical scrubbing, ultrasonic removal, and heavy-metal ion electrolysis, are constrained by high cost, operational complexity, and ecological hazards. Antifouling coatings have emerged as a cost-effective alternative, yet early formulations based on asphalt, tar, and lead posed environmental risks, and tributyltin (TBT) self-polishing coatings were globally banned in 2008 due to toxicity and bioaccumulation. Hydrogel coatings have attracted considerable interest because of their biocompatibility, low toxicity, and environmentally friendly characteristics. This review synthesizes the application of hydrogel coatings in marine antifouling, systematically analyzing molecular design and network structure regulation achieved through various crosslinking strategies, and elucidating antifouling mechanisms. It summarizes antifouling performance in laboratory and field environments, examines composite and multifunctional hydrogel coatings for enhanced overall performance, and discusses developmental potential. Current limitations of hydrogel antifouling coatings are analyzed and future research directions proposed, intending to provide theoretical insights for effective and environmentally responsible marine antifouling solutions.