Monocrystalline InP Thin Films with Tunable Surface Morphology and Energy Band gap

Effect of the Indentation Load on the Raman Spectra of the InP Crystal

Nanoindentations and the Raman spectroscopy measurements were carried out on the (001) surface of undoped and S-doped InP crystal. The samples were indented with the maximum load ranging from 15 mN to 100 mN. The phase transition B3→B1 was not confirmed by spectroscopic experiments, indicating a plastic deformation mechanism governed by dislocations activity. Increasing the maximum indentation load shifts and the longitudinal and transverse optical Raman bands to lower frequencies reveals a reduction in the elastic energy stored in the plastic zone right below the indentation imprint. Mechanical experiments have shown that a shift in Raman bands occurs alongside the indentation size effect. Indeed, the hardness of undoped and S-doped InP crystal decreases as a function of the maximum indentation load.

Thin silicon via crack-assisted layer exfoliation for photoelectrochemical water splitting

Silicon (Si) has been widely investigated as a feasible material for photoelectrochemical (PEC) water splitting. Compared to thick wafer-based Si, thin Si (<50 μm thickness) could concurrently minimize the material usage allowing the development of cost-effective and flexible photoelectrodes for integrable PEC cells. This work presents the design and fabrication of thin Si using crack-assisted layer exfoliation method through detailed optical simulations and a systematic investigation of the exfoliation method. Thin free-standing Si photoanodes with sub-50 μm thickness are demonstrated by incorporating a nickel oxide (NiO_x) thin film as oxygen evolution catalyst, light-trapping surface structure, and a rear-pn⁺ junction, to generate a photo-current density of 23.43 mA/cm² with an onset potential of 1.2 V (vs. RHE). Our work offers a general approach for the development of efficient and cost-effective photoelectrodes with Si films with important implications for flexible and wearable Si-based photovoltaics and (opto)electronic devices.

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Design and fabrication of thin Si photoanode using crack-assisted layer exfoliation

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A systematic investigation of the crack-assisted layer exfoliation method

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Optical simulation on the dependence of photoelectrochemical performance on Si thickness

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Demonstration of thin Si photoanode with notable photoelectrochemical performance