High-Throughput Deposition of Recyclable SnO2 Electrodes toward Efficient Perovskite Solar Cells.

Chemical bath deposited (CBD) SnO2 is one of the most prevailing electron transport layers for realizing high-efficiency perovskite solar cells (PSCs) so far. However, the state-of-the-art CBD SnO2 process is time-consuming, contradictory to its prospect in industrialization. Herein, a simplified yet efficient method is developed for the fast deposition of SnO2 electrodes by incorporating a concentrated Sn source stabilized by the ethanol ligand with antimony (Sb) doping. The higher concentration of Sn source promotes the deposition rate, and Sb doping improves the hole-blocking capability of the CBD SnO2 layer so that its target thickness can be reduced to further save the deposition time. As a result, the deposition time can be appreciably reduced from 3-4 h to only 5 min while maintaining 95% of the maximum efficiency, indicating the power of the method toward high-throughput production of efficient PSCs. Additionally, the CBD SnO2 substrates are recyclable after removing the upper layers of complete PSCs, and the refurbished PSCs can maintain ≈98% of their initial efficiency after three recycling-and-fabrication processes.

[TG-fTIR study of the thermal-conversion properties of holo-cellulose derived from woody biomass].

Thermal-conversion properties of cellulose, hemi-cellulose and holo-cellulose derived from woody biomass were studied using TG-FTIR, and also compared to those of avicel cellulose and xylan. 3-D diffusion model was applied to calculate the kinetic parameters of thermal-conversion reaction of biomass materials, such as the activation energy, pre-exponential factors, etc, which showed good regression results. With the analysis of three-dimensional IR spectra of gas products, featured peaks of HzO, CO, CO2, CH4, and oxygenates were obviously observed where showing up with the maximum weight-loss rate in DTG curves. The possible forming routes of major gaseous products were analyzed and discussed. The order of releasing amounts for gaseous productions was approximately as CO2 > H2O > CO CH4. Based on the comprehensive understanding and comparative analysis of the whole results, it is concluded that the thermal conversion process of holo-cellulose was the result of interaction between cellulose and hemi-cellulose under the dominant role of cellulose.