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To prepare a hierarchical micro-nano structure FeF3·0.33H2O simply and economically, a one-pot method with dual surfactants was used. Scanning electron microscopy and a Fourier transformation infrared spectrometer revealed that polyvinyl pyrrolidone (PVP) regulates the morphology of the material, while cetyltrimethylammonium bromide (CTAB) can reshape FF@PVP, it can not only remove PVP at room temperature, but also obtain a hierarchical micro-nano structure. The electrochemical results show that the hierarchical micro-nano structure FF(1.5CTAB 0.5PVP) has the best electrochemical performance. It maintained a high specific capacity of 109.4 mAh g−1 after 100 cycles at 1 C. In particular, under the ultra-high rate discharge of 20 C, the ultra-high specific discharge capacity of 66.4 mAh g−1 was reached. The FF(1.5CTAB 0.5PVP)'s excellent electrochemical performance is mainly due to a large contact area between the electrolyte and active materials. [ABSTRACT FROM AUTHOR]

Honeycomb structure is extraordinarily effective to trap light, and the efficiency of solar cell with this texture is as high as 24.4 %. In this paper, plasma immersion ion implantation and acid etching are applied to texture multi-crystalline silicon. Surface reflectivity and surface morphology are investigated by UV-Vis-NIR spectrophotometer and field emission scanning electron microscopy, respectively. We found that random nano-honeycomb structures have been formed on silicon surface. The weighted average reflectance is 7.68 % from 300 to 1,100 nm wavelength region. We obtained honeycomb-textured solar cells following standard fabrication protocol. These solar cells show obvious better performance in short circuit current density (>5.4 %) and efficiency (~0.8 % absolute) compared with acid-textured cell, while other performance parameters, such as open circuit voltage and fill factor, are not deteriorated. [ABSTRACT FROM AUTHOR]

A black silicon on emitter (BSOE) solar cell, with a uniform depletion region, was investigated by its internal quantum efficiency (IQE) and by scanning electron microscopy using an electron beam-induced current. We establish a three-dimensional energy band diagram of a non-uniform depletion region to illustrate the shunt effect by introducing a lateral electric field into the black silicon solar cell. The IQE spectral response at 450nm is enhanced by ∼31%. The conversion efficiency is improved by 0.8% abs compared with a black silicon solar cell. [Copyright &y& Elsevier]

Abstract: In the present study, the black silicon has been successfully produced by plasma immersion ion implantation (PIII). The microstructure and the reflectance of the black silicon have been investigated by field emission scanning electron microscope and spectrophotometer, respectively. Results show that the black silicon exhibits a needle-like structure with the average reflectance of 1.79%. The solar cell based on black silicon yields an efficiency of 15.68% with a fill factor (FF) of 0.783. [Copyright &y& Elsevier]

Abstract: In this paper, we report a simple method to produce micro/nano dual-scale textured silicon surfaces by combining alkaline etching with plasma surface processing. The surface morphologies were investigated by a field emission scanning electron microscope, while the surface reflectance and wettability were examined by a UV–VIS-NIR spectrophotometer and a drop shape analysis system, respectively. Results show that random nano-scale needle-like structures have been formed on micro-scale pyramids. The average reflectance and contact angle are 2.8% and ~120°, respectively. The solar cell based on the dual-scale textured silicon yields a high efficiency of 17.5% with a short circuit current density of 36.0mA/cm2. [Copyright &y& Elsevier]