Rong Li,Jiale Ding,Xijiao Mu,Yifei Kang,Anran Wang,Weihui Bi,Yunhe Zhang,Jing Cao,Qingfeng Dong
The extreme instability of pure α-phase FAPbI 3 under high humidity conditions restricts the high-throughput fabrication in unmodified air environments, resulting in poor performance of α-phase FAPbI 3 perovskite devices obtained by scalable fabrication methods. Here we synthesized hyperbranched copper phthalocyanine (HCuPc) as a supramolecular additive with twisted phthalocyanine units to realize the molecular-level encapsulation at the grain boundaries through supramolecular interaction, which greatly broadened the processing window of FAPbI 3 under high humidity. At the same time, unlike traditional encapsulation layer that carrier can only be collected by tunneling effect, the twisted phthalocyanine ring of HCuPc in perovskite films is more conducive to hole extraction. Finally, a record efficiency was achieved in pure FAPbI 3 based inverted structured solar cell by blade-coating to the best of our knowledge, even under unmodified humid air conditions (relative humidity of 65%–85%). The best operational stability of 3D pure FAPbI 3 devices can also be achieved at the same time and unencapsulated HCuPc-FAPbI 3 device can even operate with negligible degradation for 100 h in the open air (RH 30%–40%).
As an antibiotic, tetracycline has been widely used against bacterial infection or as feed additives for growth promotion, which may lead to the enrichment of antibiotic residues in animals or their products. Therefore, the detection of tetracycline is closely related to human health. The morphological transformation of CoOOH nanoflakes induced by tetracycline was monitored by scanning electron microscope images, dark-field light scattering images and optical spectra, which found that tetracycline could decompose CoOOH nanoflakes into small nanoparticles with low light scattering signal. As a result, the reduced light scattering of CoOOH nanoflakes was proportional to the increased concentration of tetracycline in the range of 1.0–250 μmol/L, and the limit of determination (LOD) was 0.23 μmol/L (3σ/k). Most foreign substances did not interfere in the analysis of tetracycline. Furthermore, the concentration of tetracycline in different milk samples detected with the standard addition method was so low that it accorded with the safety regulation, which was similar to the detection result with high-performance liquid chromatography (HPLC).