RESUMEN
SiO2 nanomaterials are widely used for antireflection and self-cleaning, but the preparation process is usually complex and time-consuming. Hence, we present a facile one-step synthesis of a hydrophobic two-dimensional SiO2 nanomesh by tuning the reaction temperature using dodecylamine as a catalyst. SiO2 nanomesh has the advantages of an adjustable refractive index, simple preparation process, and low cost, which affords both antireflection and self-cleaning functions for solar cells. Two types of perovskite solar cells were used to verify the stability and universality of the SiO2 nanomesh coatings. The antireflection effect of the SiO2 nanomesh is found to increase the current density of both perovskite solar cells fabricated at 500 °C and 150 °C, with the efficiency increased by 4.48% and 4.79%, respectively.
RESUMEN
Interface passivation in the electron transport layer (ETL) has emerged as a very important and challenging topic for the improvement of stability and efficiency of perovskite solar cells (PSCs). Here, we introduce the n-type small organic molecule Y6 that acts as an effective ETL modifier through surface engineering. As a result, the simple PCBM + Y6 ETL led to significantly stronger light absorption, higher electron extraction ability and transportability, and reduced recombination loss in regular MAPbI3 PSCs. The power conversion efficiency can be significantly increased from 17.39 to 20.02% in inverted p-i-n MAPbI3 PSCs without additional alternation, with an increment of over 15%, along with higher open-circuit voltage and short-circuit current. What is more, the devices with the Y6-modified ETL also exhibited better long-term stability compared to the control devices. This indicates the feasibility of enhancing absorption over a wider light spectrum in a single-junction cell and gaining a comprehensive understanding of interface engineering between the ETL and perovskite layer.
RESUMEN
Alkali halide perovskites have emerged as representative candidates for novel opto-electronic devices owing to their balanced efficiency and stability. However, their fabrication method still remains a challenging topic with conflicts among their effectiveness, complexity, and cost. Herein, a complete two-step electrochemical method has been applied in the fabrication of inorganic perovskites for the first time. The dimension and microstructure of CsPbBr3 can be easily controlled by variation of simple physical parameters during the fabrication. By optimizing the parameters, high-quality CsPbBr3 films are obtained, and the champion device has achieved an efficiency of 7.86% with a high open-circuit voltage of 1.43 V. More importantly, the as-fabricated materials have shown an extraordinary robust stability against environmental conditions even after 150 days of exposure to air without encapsulation. This has evidently proved the electrochemical methods as an effective route for perovskite synthesis in its future development.
RESUMEN
Microwave bandpass filter structure has been designed and fabricated by filling the periodically metallic apertures with dielectric particles. The microwave cannot transmit through the metallic subwavelength apertures. By filling the metallic apertures with dielectric particles, a transmission passband with insertion loss 2 dB appears at the frequency of 10-12 GHz. Both simulated and experimental results show that the passband is induced by the Mie resonance of the dielectric particles. In addition, the passband frequency can be tuned by the size and the permittivity of the dielectric particles. This approach is suitable to fabricate the microwave bandpass filters.