Enhancing the efficiency of hybrid Schottky diode by decoration of 2D Cs:ZnO nanosheets with CNTs via a facile co-precipitation approach

Abstract The Cs:ZnO@CNTs nanocomposite was synthesized by chemical co-precipitation method and characterized using XRD, EDX, SEM, and TEM techniques, which revealed small crystalline size, high atomic density, and large surface area. The thin films showed intense optical absorption near the visible region with optical band gaps of 3.12 eV and 3.06 eV for Cs:ZnO and Cs:ZnO@CNTs nanostructures, respectively. The hybrid Schottky diode was fabricated by depositing Cs:ZnO nanosheets on p-Si using drop casting technique and the metal contacts were thermally deposited via thermal evaporation technique. The electronic parameters were evaluated in a dark environment, revealing reduced series resistance <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mo stretchy="false">(</mml:mo> <mml:mi mathvariant="normal">R</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">s</mml:mi> </mml:mrow> </mml:msub> <mml:mo stretchy="false">)</mml:mo> </mml:math> and a decreased potential barrier <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mo stretchy="false">(</mml:mo> <mml:mi>ϕ</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">b</mml:mi> <mml:mo stretchy="false">)</mml:mo> </mml:mrow> </mml:msub> </mml:math> relative to the undoped diode. The photodiode demonstrated elevated responsivity and specific detectivity under illumination conditions influenced by CNT additions, which expanded optical absorption and increased photocarrier density. The <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi mathvariant="normal">C</mml:mi> <mml:mo>/</mml:mo> <mml:mi mathvariant="normal">G</mml:mi> <mml:mo>−</mml:mo> <mml:mi mathvariant="normal">V</mml:mi> </mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">R</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">s</mml:mi> </mml:mrow> </mml:msub> <mml:mo>−</mml:mo> <mml:mi mathvariant="normal">V</mml:mi> </mml:math> measurements were executed over a wide frequency range, indicating the significant impact of trapped centers at interfacial layers on capacitance, conductance, and series resistance characteristics. The obtained results confirmed the potential use of hybrid photoactive materials in the development of solar power devices.