In inverted perovskite solar cells (PSCs), effective modification of the interface between the metal cathode and electron transport layer (ETL) is crucial for achieving high performance and stability. Herein, sulfonated bathocuproine, commonly known as disodium bathocuproine disulfonate (BCDS), was employed as a cathode buffer layer to address the interfacial issues at the [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)/Ag interface. BCDS possesses the ability to form coordinate bonds with Ag electrodes. The utilization of the BCDS buffer layer enhanced the charge extraction capability at the cathode interface while simultaneously achieving interfacial defect passivation, improving interfacial contact, and increasing the built-in electric field. Consequently, a power conversion efficiency (PCE) of 25.06% was achieved. Furthermore, owing to the excellent film-forming uniformity of BCDS on PCBM, the stability of the device was also improved. After storage in dry air for more than 2000 h, the device maintained 96% of its initial efficiency. This work underscores the remarkable potential of tailoring coordination groups to enhance charge extraction efficiency at the ETL-cathode interface, unveiling a promising new frontier in buffer layer development and performance optimization strategies for PSCs.

The development of three-dimensional (3D) space light angle detection is vital in optical technology for applications such as 3D imaging, computer vision, and augmented reality. Current methods involve advanced sensors and algorithms, including time-of-flight cameras, which need multiple cameras and light sources to improve accuracy. However, it is a great challenge to integrate these complex components into compact devices. Subwavelength semiconductor structures offer optical resonance characteristics, enabling precise light–matter interaction regulation. A 3D star-like photodetector, fabricated using a template assistant printing strategy, demonstrates optical resonances of the subwavelength facade and the shielding effect of spatial arrangement. It achieves light angle detection with the resolution of 10° in vertical space and the resolution of 36° in horizontal space, making it a promising prototype for various applications.

Perovskite solar cells (PSCs) have seen remarkable progress in recent years, largely attributed to various additives that enhance both efficiency and stability. Among these, fluorine-containing additives have garnered significant interest because of their unique hydrophobic properties, effective defect passivation, and regulation capability on the crystallization process. However, a targeted structural approach to design such additives is necessary to further enhance the performance of PSCs. Here, fluoroalkyl ethylene with different fluoroalkyl chain lengths (CH₂CH(CF₂)_nCF₃, n = 3, 5, and 7) as liquid additives is used to investigate influences of fluoroalkyl chain lengths on crystallization regulation and defect passivation. The findings indicate that optimizing the quantity of F groups plays a crucial role in regulating the electron cloud distribution within the additive molecules. This optimization fosters strong hydrogen bonds and coordination effects with FA⁺ and uncoordinated Pb²⁺, ultimately enhancing crystal quality and device performance. Notably, 1H,1H,2H-perfluoro-1-hexene (PF₃) with the optimal number of F presents the most effective modulation effect. A PSC utilizing PF₃ achieves an efficiency of 24.05%, and exhibits exceptional stability against humidity and thermal fluctuations. This work sheds light on the importance of tailored structure designs in additives for achieving high-performance PSCs.

Precise and sensitive bioanalysis has been the major and urgent pursuit in pathologic diagnosis, food safety, environment monitoring, and drug evaluation. Photoelectrochemical (PEC) bioanalysis, as one of the most promising detection technologies, has rapidly expanded within the field of analysis. However, most of reported PEC analysis approaches still suffer from weak external anti-interference ability, high background, and the risk of false positive or negative errors due to their inherent single-signal readout. To overcome these shortcomings, new PEC-coupled dual-modal analysis approaches have been developed, where a dual-response signal can be derived through two completely different mechanisms and independent signal transduction pathways. This review introduces the basic principles of PEC biosensing and enumerates and classifies the substrate or probe selections, constructions, and applications of PEC-coupled dual-modal biosensors. Furthermore, the challenges and developmental prospects of PEC-coupled dual-mode sensing technologies are evaluated and discussed. We hope that this review will provide valuable insights into the latest advancements and practical applications of dual-mode PEC bioanalysis, which will be of great interest to those seeking to stay informed in this field.

Metal-halide perovskite solar cells have garnered significant research attention in the last decade due to their exceptional photovoltaic performance and potential for commercialization. Despite achieving remarkable power conversion efficiency of up to 26.1%, a substantial discrepancy persists when compared to the theoretical Shockley–Queisser (SQ) limit. One of the most serious challenges facing perovskite solar cells is the energy loss incurred during photovoltaic conversion, which affects the SQ limits and stability of the device. More significant than the energy loss occurring in the bulk phase of the perovskite is the energy loss occurring at the surface-interface. Here, we provide a systematic overview of the physical and chemical properties of the surface-interface. Firstly, we delve into the underlying mechanism causing the energy deficit and structural degradation at the surface-interface, aiming to enhance the understanding of carrier transport processes and structural chemical reactivity. Furthermore, we systematically summarized the primary modulating pathways, including surface reconstruction, dimensional construction, and electric-field regulation. Finally, we propose directions for future research to advance the efficiency of perovskite solar cells towards the radiative limit and their widespread commercial application.

The booming development of wearable devices has aroused increasing interests in flexible and stretchable devices. With mechanosensory functionality, these devices are highly desirable on account of their wide range of applications in electronic skin, personal healthcare, human–machine interfaces and beyond. However, they are mostly limited by single electrical signal feedback, restricting their diverse applications in visualized mechanical sensing. Inspired by the mechanochromism of structural color materials, interactively stretchable electronics with optical and electrical dual-signal feedbacks are recently emerged as novel sensory platforms, by combining both of their sensing mechanisms and characteristics. Herein, recent studies on interactively stretchable electronics based on structural color materials are reviewed. Following a brief introduction of their basic components (i.e., stretchable electronics and mechanochromic structural color materials), two types of interactively stretchable electronics with respect to the nanostructures of mechanochromic materials are outlined, focusing primarily on their design considerations and fabrication strategies. Finally, the main challenges and future perspectives of these emerging devices are discussed.

Localized surface plasmon resonance (LSPR) has been widely used in medical detection because of its time effectiveness, non-invasiveness, high sensitivity, and relatively simple fabrication process. Porous anodic alumina (PAA) can be regarded as a plasma substrate for label-free detection due to its unique two-dimensional structure. In this work, a vivid Au-PAA composite film with the inverted taper structure was developed by multi-step anodic oxidation and pore-widening processes followed by magnetron sputtering with Au nanoparticles (AuNPs). The highly saturated and bright structural color was generated by the synergistic effect of photonic and plasmonic modes. Interestingly, various Au-PAA composite films with structural colors altering from purple to red were obtained via adjusting the height/diameter ratio of PAA. Benefiting from the inverted taper structure, light trap characteristics were effectively enhanced by increasing the incident light and reducing the diffuse light. In addition, a finite difference time domain (FDTD) model was proposed to predict the relationship between the reflectance peak and the height of the composite film, and the simulated data were in good agreement with the experimental results. As a proof of concept, label-free detections of various reagents (water, ethanol, glycol, glycerol, and glucose), the concentration of glucose (refractive index sensitivity of 376 nm/RIU, RIU: refractive index unit), and thrombin (detection limit of 0.1 × 10⁻⁷ mol/L) were realized by the Au-PAA composite film. This vivid Au-PAA composite film provides a very powerful tool for in-situ label-free bio-detection.

Reaction kinetics of nanoparticles can be controlled by tuning the Peclet number (Pe) as it is an essential parameter in synthesis of multi-sized nanoparticles. Herein, we propose to implement a self-driven multi-dimension microchannels reactor (MMR) for the one droplet synthesis of multi-sized nanoparticles. By carefully controlling the Pe at the gas–liquid interface, the newly formed seed crystals selectively accumulate and grow to a specific size. By the combination of microchannels of different widths and lengths, one droplet reaction in the same apparatus achieves the synchronous synthesis of diverse nanoparticles. MMR enables precise control of nanoparticle diameter at 5 nm precision in the range of 10–110 nm. The use of MMR can be extended to the synthesis of uniform Ag, Au, Pt, and Pd nanoparticles, opening towards the production and engineering of nanostructured materials. This approach gives the chance to regulate the accumulation probability for precise synthesis of nanoparticles with different diameters.

The development of an efficient Pt-based electrocatalyst in acidic and alkaline electrolytes is of great significance to the field of electrocatalytic hydrogen evolution. Herein, we report a strategy for in situ growth of Pt₃Ni truncated octahedrons on Ti₃C₂T_x nanosheets and then obtain an ordered porous catalyst via a template method. Meanwhile, we use the finite element calculation to clarify the relationship between the component structure and performance and find that the performance of the spherical shell microstructure catalyst is higher than that of the disc structure catalyst, which is also verified by experiments. The experimental analysis shows that the ordered porous catalyst is conducive to enhancing electrocatalytic hydrogen evolution activity in acidic and alkaline electrolytes. In an acidic solution, the overpotential is 25 mV (10 mA·cm⁻²), and the Tafel slope is 22.86 mV·dec⁻¹. In an alkaline solution, the overpotential is 44.1 mV (10 mA·cm⁻²), and the Tafel slope is 39.06 mV·dec⁻¹. The synergistic coupling between Ti₃C₂T_x and Pt₃Ni nanoparticles improves the stability of the catalyst. The in situ growth strategy and design of microstructure with its correlation with catalytic performance represent critical steps toward the rational synthesis of catalysts with excellent catalytic activity.

Perovskite single-crystal arrays have attracted intensive attention because of their great potentials for integrated optoelectronic devices. However, the traditional top-down lithography strategy requires complex processing and is detrimental to perovskite crystal structures, which is incompatible to directly pattern perovskite single crystals. Herein, we report a lithography-free method to realize the controllable growth of perovskite single-crystal arrays. Through introducing a printed hydrophilic-hydrophobic substrate into the crystallization system, the MAPbCl₃ single-crystal arrays with precise location and uniform size are effectively fabricated. This method can be applied to prepare diverse perovskite single-crystal arrays, including MAPbBr₃, CsPbCl₃, CsPbBr₃, Cs₃Cu₂I₅, Cs₃Bi₂I₉, and (BA)₂(MA)₃Pb₄I₁₁. The perovskite single crystals can be selectively grown on the electrodes to fabricate ultraviolet photodetectors. The strategy demonstrates a facile approach to fabricate large-scale perovskite single-crystal arrays and opens a pathway to produce diverse perovskite optoelectronic devices.