On December 26, 2025, the Yang Group held its annual year-end dinner at Nancun Wanbo. Prof. Yang invited all 16 members of the group (including two postdoctoral researchers and three undergraduates) to gather together and celebrate the arrival of 2026. Prof. Yang expressed gratitude to everyone and extended sincere New Year’s wishes. It is believed that in 2026, the Yang group will continue to make steady progress in scientific research and create more memorable moments together. With the New Year just around the corner, we wish each member every success in their work and happiness in their personal lives in the year ahead. We look forward to getting together again next year.

Colloidal silicon and germanium nanocrystals (Si/Ge NCs) have been of immense interest as fundamentally important semiconductor nanomaterials in the past decades due to their distinct covalent bonding characteristics, quantum-confined optoelectronic properties, high materials stability and biocompatibility. Significant advances in surface chemistry have enabled these NCs to serve as versatile material platforms where precisely engineered ligand environments control optical responses, charge transport behaviors, and device performance. This review systematically examines the evolution of surface functionalization strategies, encompassing both conventional passivation methods and innovative ligand architectures, for the property manipulation of Si/Ge NCs. The critical role of surface chemistry in enabling diverse applications, including optical devices, optoelectronic devices, and energy conversion/storage systems, is comprehensively discussed. Special attention is given to elucidating the fundamental relationships between surface chemical modifications, nanocrystal properties, and their resulting device performance.
Journal Feature：https://mp.weixin.qq.com/s/pIaLyDrmufN3HVB-OTgMOw
Paper Link：https://doi.org/10.1039/D5QM00646E

Our joint research on quantum well-based red light-emitting diodes was recently published in InfoMat. This paper develops a colloidal quantum well light-emitting diode with long-wavelength emissions. The research significantly improved charge balance within the device by designing and implementing a triple-hole transport layer structure that effectively regulates the internal charge distribution. The fabricated quantum well films exhibit high photoluminescence quantum yield. The resulting LEDs demonstrated high external quantum efficiency, high luminance, extremely low efficiency roll-off, and excellent color saturation and stability. This charge regulation strategy was proven to be universal, effectively enhancing the performance of other-color quantum well LEDs and even quantum dot LEDs. This work provides a new approach and an effective charge management method for developing high-performance two-dimensional nanocrystal LEDs, particularly in the long-wavelength emission region.
Paper Link：https://doi.org/10.1016/j.nanoen.2025.111026

A collaborative review on the recent progress of perovskite solar cells was recently published in Advanced Materials, This review provides a systematic overview of the overall development of diverse perovskite solar cells. It encompasses major material systems including organic-inorganic hybrid perovskites, all-inorganic perovskites, lead-free perovskites, and metal-free perovskites, extending the discussion to low-dimensional and single-crystal perovskites. The article highlights that despite significant progress in laboratory efficiency, the commercial viability of perovskite solar cells continues to be hindered by fundamental challenges such as instability, lead toxicity, and difficulties in large-area fabrication. To address these issues, the field is focusing on strategies like composition engineering, dimensional control, interface modification, and defect passivation to enhance material properties and device stability. Future advancement hinges on balancing high efficiency with robust stability, developing environmentally benign materials, and facilitating the transition from laboratory research to industrial application.
Paper Link：https://doi.org/10.1002/adma.202512221

The paper is titled “Direct Dehydrocoupling Facilitates Efficient Thiophene Anchoring on Silicon Surfaces”. Silicon is a cornerstone material in electronics and photovoltaics due to its abundance, tunable semiconducting properties, and chemical versatility. Direct anchoring of thiophenes, with their highly delocalized aromatic backbones, onto silicon surfaces offers a promising route to tailor charge carrier migration properties. However, current methods for anchoring thiophenes commonly rely on pre-activation of precursors or transition-metal catalysts. Here, we introduce a catalyst-free radical strategy for direct linkage of thiophenes with Si atoms on organosilanes and silicon surfaces. This method leverages thermally induced homolytic cleavage of Si-H bonds to generate silicon radicals, which undergo efficient hydrosilylation with thiophene rings, forming Si-C linkages and releasing H2. We demonstrate the successful application of this approach on silicon surfaces, achieving functionalization with thiophenes that enhance charge carrier mobilities in silicon nanocrystals significantly higher than previously reported alkyl-functionalized SiNCs, indicating the significant potential of catalyst-free dehydrocoupling for advancing silicon-based materials in optoelectronic applications.
Paper Link：https://doi.org/10.1038/s41467-025-62002-7

On July 18, 2025, Ms. Wenxuan Li (Ph.D. Candidate) attended the 50th World Chemistry Congress in Kuala Lumpur, Malaysia, where she delivered an academic presentation titled “Branched-Cation Engineered 2D Perovskite Materials: Structural Evolution and Optoelectronic Applications” in the Inorganic and Bioinorganic Chemistry sub-forum. Her presentation highlighted the research progress in molecular design strategies for structural modulation and optoelectronic property optimization of two-dimensional metal halide perovskites.

The paper is titled “Enhancing charge carrier mobilities in colloidal germanium quantum dot solids via solid-state ligand exchange”. The optoelectronic tunability and solution processability of colloidal germanium quantum dots (GeQDs) make them highly attractive as active materials for thin film optoelectronics. However, while long-chain aliphatic ligands can effectively protect GeQD surfaces from oxidation and enhance colloidal stability, their insulating nature severely impedes charge carrier transport within the GeQD active layer. In this study, we introduce a solid-state ligand exchange (SSLE) approach using methylammonium iodide (MAI) to replace the insulating oleylamine ligands, thereby enhancing charge carrier mobilities in the GeQD thin film. We demonstrate that a low concentration of MAI effectively substitutes OAm on GeQD surfaces while preserving the structural integrity of the crystalline core. The resulting MAI-passivated GeQD films exhibit significantly reduced trap densities and enhanced hole and electron mobilities compared to their OAm-passivated counterparts. Furthermore, we fabricate solar cells using a layer-by-layer SSLE process to construct a multilayered GeQD active layer, achieving a power conversion efficiency of up to 1.64 × 10-3 %, a significant improvement over previously reported GeQD photovoltaics.
Paper Link：https://doi.org/10.1021/acsaelm.5c00777

On July 7, 2025, Ms. Meiqi Lin (Ph.D. Candidate) attended China Materials Conference 2025 in Xiamen and delivered an academic presentation titled “Doping-Assisted Synthesis and Ligand Engineering of Colloidal Germanium Quantum Dots for Photovoltaic Applications” at the Frontier Flash Talks for Young Scholars sub-forum. Her report focused on the fabrication of high-performance optoelectronic devices using colloidal germanium quantum dots (GeQDs), highlighting her research group’s latest advances in doping-assisted synthesis and surface modification strategies for GeQDs.

The paper is titled “Solid-state synthesis of colloidal tin-incorporated silicon nanocrystals”. The incorporation of tin (Sn) into crystalline silicon (c-Si) is challenging due to their substantial atomic size mismatch and the rigid diamond-type structure of c-Si. Herein, we demonstrate a solid-state synthetic approach of colloidal Sn-incorporated silicon nanocrystals with Sn content up to 0.12 atomic%. The incorporation of Sn atoms promotes silicon crystal growth, yielding NCs with increased size and enhanced crystallinity. The resulting particles exhibit intense near-infrared photoluminescence at 985 nm and demonstrate excellent thermal stability.
Paper Link：https://doi.org/10.1039/D5CC03024B

On May 16, 2025, Ms. Guoying Yao successfully completed her doctoral dissertation defense in Room B413 at the School of Chemistry, Sun Yat-sen University. The dissertation titled “Theoretical Studies on the Optoelectronic Properties of Two-Dimensional Silane” systematically investigated the regulation mechanisms of optoelectronic properties in two-dimensional silane materials. The defense committee consisted of Professor Zhiji Han (Chair) from Sun Yat-sen University, Assistant Professor Yongqing Cai from University of Macau, Professor Jun He from Guangdong University of Technology, Professor Jiuxing Jiang, Associate Professor Wen Shi, and Associate Professor Yecheng Zhou from Sun Yat-sen University. All members of the research group extend their congratulations to Ms. Guoying Yao and wish her greater achievements in the future!

On May 15, 2025, Professor Cai Yongqing from the University of Macau was invited to visit and delivered an academic lecture titled “Material Design Based on First-Principles Calculations” in Room A301 of the School of Chemistry. The lecture focused on the latest research progress in phase engineering and catalytic design of two-dimensional materials. The lecture was chaired by Professor Zhenyu Yang, with active participation and discussion from faculty members and students.

Our team contributed in collaborative research on quantum dot-based infrared photodetectors, with the finings published in Nano Energy, A novel zinc halide-controlled synthesis method has successfully produced highly monodisperse Ag2Te colloidal quantum dots. By forming silver-halogen complexes to regulate precursor reactivity, this approach enables one-step hot injection synthesis of uniformly sized quantum dots with tunable optical bandgaps. The strategy not only simplifies the process but also significantly enhances surface passivation, effectively reducing defect states. The resulting short-wave infrared photodetectors demonstrate excellent overall performance at 1550 nm, featuring high responsivity and external quantum efficiency while maintaining low noise levels and good operational stability. This advancement provides a new technical pathway for developing environmentally friendly, high-performance infrared detection materials.
Paper Link：https://doi.org/10.1002/inf2.70099