**4. Conclusion**

In summary, facile silicon surface modification methods based on one or two MACE to synthesis PSiNWs were presented. The change in morphology based on HF or H<sup>2</sup> O2 effect was presented. Furthermore, this change also affects the optical properties specially the photoluminescence and compensates the poor light absorption of the planar silicon substrate. Several emerging strategies result in high-performance hybrid solar cells based on PSiNWs were presented. These strategies are based on the organic materials or/and the design of the solar cells or on the grid electrode as a contact. These findings could be potentially employed to further reduce the fabrication cost of silicon solar cells by reducing the consumption of silicon materials and increasing their efficiency.

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