Lejda Katarzyna, Ziąbka Magdalena, Olejniczak Zbigniew, Janik Jerzy Franciszek
Faculty of Energy and Fuels, AGH University, al. Mickiewicza 30, 30-059 Krakow, Poland.
Faculty of Materials Science and Ceramics, AGH University, al. Mickiewicza 30, 30-059 Krakow, Poland.
Materials (Basel). 2023 Sep 11;16(18):6160. doi: 10.3390/ma16186160.
The often overlooked and annoying aspects of the propensity of no-oxygen semiconductor kesterite, CuZnSnS, to oxidation during manipulation and storage in ambient air prompted the study on the prolonged exposure of kesterite nanopowders to air. Three precursor systems were used to make a large pool of the cubic and tetragonal polytypes of kesterite via a convenient mechanochemical synthesis route. The systems included the starting mixtures of (i) constituent elements (2Cu + Zn + Sn + 4S), (ii) selected metal sulfides and sulfur (CuS + ZnS + SnS + S), and (iii) in situ made copper alloys (from the high-energy ball milling of the metals 2Cu + Zn + Sn) and sulfur. All raw products were shown to be cubic kesterite nanopowders with defunct semiconductor properties. These nanopowders were converted to the tetragonal kesterite semiconductor by annealing at 500 °C under argon. All materials were exposed to the ambient air for 1, 3, and 6 months and were suitably analyzed after each of the stages. The characterization methods included powder XRD, FT-IR/UV-Vis/Raman/NMR spectroscopies, SEM, the determination of BET/BJH specific surface area and helium density (d), and direct oxygen and hydrogen-content analyses. The results confirmed the progressive, relatively fast, and pronounced oxidation of all kesterite nanopowders towards, mainly, hydrated copper(II) and zinc(II) sulfates, and tin(IV) oxide. The time-related oxidation changes were reflected in the lowering of the energy band gap E of the remaining tetragonal kesterite component.
在空气中处理和储存期间，无氧半导体硫锡铜矿（CuZnSnS）易于氧化，这一特性中那些常常被忽视且令人烦恼的方面促使人们对硫锡铜矿纳米粉末在空气中的长时间暴露展开研究。通过便捷的机械化学合成路线，使用了三种前驱体体系来制备大量立方和四方多型的硫锡铜矿。这些体系包括：（i）组成元素（2Cu + Zn + Sn + 4S）的起始混合物；（ii）选定的金属硫化物和硫（CuS + ZnS + SnS + S）；（iii）原位制备的铜合金（由2Cu + Zn + Sn金属的高能球磨制得）和硫。所有原始产物均显示为具有失效半导体性能的立方硫锡铜矿纳米粉末。通过在氩气气氛下500℃退火，这些纳米粉末被转化为四方硫锡铜矿半导体。所有材料在环境空气中暴露1、3和6个月，并在每个阶段后进行适当分析。表征方法包括粉末XRD、FT-IR/UV-Vis/拉曼/NMR光谱、SEM、BET/BJH比表面积和氦密度（d）的测定，以及直接的氧和氢含量分析。结果证实，所有硫锡铜矿纳米粉末都朝着主要为水合硫酸铜（II）和硫酸锌（II）以及二氧化锡（IV）的方向进行渐进、相对快速且明显的氧化。与时间相关的氧化变化反映在剩余四方硫锡铜矿组分的能带隙E的降低上。
