Chunlei Huang

Organic–inorganic hybrid perovskite solar cells (PSCs) have achieved remarkable progress, yet further enhancements in efficiency and stability are required for commercialization. Herein, we introduce 4‐bromo‐2‐thiophenecarboxylic acid (BTCA) as a multifunctional small‐molecule additive to simultaneously regulate crystallization, passivate defects, and optimize energy level alignment. The carboxyl group (–COOH) coordinates with undercoordinated Pb2+, the bromine atom fills iodine vacancies, and the thiophene ring enhances charge transport. Systematic characterizations reveal the working mechanism. BTCA delays crystallization via dual anchoring with Pb2+ and FA+, yielding highly crystalline films with large columnar grains, reduced trap density (Urbach energy drops from 72.36 to 57.62 meV), and uniform surface potential. The modified films exhibit longer carrier lifetime (1430.63 ns vs. 1099.96 ns), suppressed non‐radiative recombination, and improved energy level alignment with the electron transport layer. Consequently, BTCA‐treated devices achieve a champion power conversion efficiency (PCE) of 25.63% (vs. 23.39% for the control), with increased open‐circuit voltage (1.188 V) and fill factor (84.16%). Unencapsulated devices retain 81.48% of their initial efficiency after 60 days under ambient conditions, compared to 73.20% for control. This work demonstrates a versatile molecular design strategy for efficient and stable PSCs.

Practical applications of next-generation stretchable electronics hinge on the development of sustained power supplies to drive highly sensitive on-skin sensors and wireless transmission modules. Although the manufacture of stretchable self-charging power units has been demonstrated by integrating stretchable energy harvesters and power management circuits with energy storage units, they often suffer from low and unstable output power especially under mechanical deformation and human movements, as well as complex and expensive fabrication processes. This work presents a low-cost, scalable, and facile manufacturing approach based on laser-induced graphene foams to yield a self-powered wireless sensing platform. 3D porous foams with high specific surface area and excellent charge transport provide an efficient flow of triboelectric electrons in triboelectric nanogenerators. The surface coating or doping with second laser irradiation on these foams can also form a 3D composite to provide high energy density in micro-supercapacitor arrays. The integration of a triboelectric nanogenerator and power management circuits with micro-supercapacitor arrays can efficiently harvest intermittent mechanical energy from body movements into stable power output. 3D foams and their composites patterned into various geometries conveniently create various deformable sensors on large scale at low cost. The generated stable, yet high, power with adjustable voltage and current outputs drives various stretchable sensors and wireless transmission modules to wirelessly measure pulse, strain, temperature, electrocardiogram, blood pressure, and blood oxygen. The self-powered, wireless, wearable sensing platform paves the way to wirelessly detect clinically relevant biophysical and biochemical signals for early disease diagnostics and healthy aging.

Development of simple and accurate methods for the detection of As ³⁺ is highly desirable and technically important. In this work, a highly sensitive and selective long-period fiber gratings sensor based on surface plasmon resonance was developed for As ³⁺ detection by designing glutathione-functionalized Au nanoparticles as a signal amplification tag. Based on the chemical interaction between As ³⁺ and glutathione, the self-assembling glutathione on the surface of the gold film combines selectively with As ³⁺ , and then anchors the glutathione-functionalized Au nanoparticles, which changes the refractive index of the surrounding environment, resulting in a shift of the transmission spectrum. Results show that the sensor could detect As ³⁺ with concentrations ranging from 0.02 to 2 ppb. The sensor exhibited excellent specificity for As ³⁺ against other metal ions, such as Na ⁺ , Fe ³⁺ , Mg ²⁺ , Cu ²⁺ , Pb ²⁺ , Ni ²⁺ , Ba ²⁺ , and Co ³⁺ . The fiber sensor was successfully employed to detect As ³⁺ in pond water samples, demonstrating that it has the potential for As ³⁺ detection with the advantages of low cost, high sensitivity, and a simple structure.