Fabrication, electrical performance analysis and photovoltaic characterization of β-H2Pc/p-Si heterojunction for solar cell device applications

Abstract

The aim of this study was to explore the potential of nanocrystalline β-metal-free phthalocyanine (β-H2Pc) in optoelectronics, particularly for the creation of a β-H2Pc/p-Si heterojunction. With a focus on photovoltaic performance, the present work aimed to assess its thermal stability, crystalline structure, optical characteristics, electrical behavior, and applicability in optoelectronic applications. We successfully fabricated a β-H2Pc/p-Si heterojunction at room temperature using a conventional high-vacuum thermal evaporation method, offering a practical approach for integrating these materials into electronic devices. Thermal gravimetric Assessment (TGA) confirmed β-H2Pc’s remarkable thermal stability up to 470 °C, which holds significant promise for high-temperature applications. Transmission Electron Microscopy (TEM) revealed the nanocrystalline nature of the deposited β-H2Pc, which is crucial for the structural integrity of advanced electronic devices. The absorption coefficient spectrum exhibited distinct absorption bands attributed to π–π* excitations, with electronic transitions identified and characterized by a 1.51 eV onset band gap and a 2.74 eV fundamental optical energy gap, highlighting its potential in optoelectronic applications. The current–voltage characteristics of the β-H2Pc/p-Si heterojunction displayed a diode-like behavior at various temperatures, with excellent rectifying properties. Photovoltaic behavior under illumination showed a power conversion efficiency of 1.1%, emphasizing its promise for renewable energy applications and future optoelectronic devices.