Scholarlink

<p>The transition to low-cost and efficient counter electrodes (CEs) is essential for the widespread deployment of dye-sensitized solar cells (DSSCs). In this study, we report copper–polypyrrole (Cu–PPy) nanocomposites synthesized via chemical reduction, which function as a noble-metal-free CE with excellent electrocatalytic behavior. The enhancement in performance is driven by <i>π</i>–d orbital interactions between the polypyrrole’s <i>π</i>-conjugated structure and the d-electrons of copper, promoting orbital hybridization that facilitates efficient electron delocalization and charge transfer at the electrode–electrolyte interface. X-ray diffraction confirms the presence of a crystalline face-centered cubic (FCC) copper phase embedded within the polymer matrix, while scanning electron microscopy reveals a porous architecture that is conducive to electrolyte infiltration. Electrochemical analyses, including chronoamperometry, cyclic voltammetry, and electrochemical impedance spectroscopy, indicate a notable decrease in charge transfer resistance (1.6&#xa0;Ω) and a substantial increase in cathodic current density (8.38&#xa0;mA&#xa0;cm<sup>−2</sup>), reflecting improved redox kinetics. The x-ray photoelectron spectroscopy (XPS) results confirm the successful integration of copper with polypyrrole, showing distinct Cu<sup>2+</sup> species and nitrogen bonding environments that support interfacial electronic coupling consistent with <i>π</i>–d orbital interaction. When incorporated into a DSSC using methyl orange as the sensitizing dye, the Cu<sub>0.2</sub>PPy CE delivered power conversion efficiency of 4.84%, rivaling traditional platinum-based electrodes. This excellent performance arises from the combined effects of orbital-level electronic synergy and nanoscale porosity, which collectively enhance interfacial charge mobility and catalytic accessibility. This work illustrates how rational design of hybrid materials at the molecular orbital level can yield high-performance, scalable alternatives to precious metals in solar energy devices.</p> Graphical Abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

π–d Orbital Synergism in Copper Polypyrrole Nanocomposites to Enhance Electrocatalytic Performance for DSSCs

  • 期刊论文

  • 发表日期：

    2026年2月19日

查看全文
  • Muhammad Usman,
  • Muhammad Musharaf,
  • Muhammad Junaid Raza,
  • Tabib ur Rehman,
  • Tehmina Mushtaq,
  • Abdul Majid,
  • Javed Iqbal,
  • Naeem Ahmed

摘要

The transition to low-cost and efficient counter electrodes (CEs) is essential for the widespread deployment of dye-sensitized solar cells (DSSCs). In this study, we report copper–polypyrrole (Cu–PPy) nanocomposites synthesized via chemical reduction, which function as a noble-metal-free CE with excellent electrocatalytic behavior. The enhancement in performance is driven by π–d orbital interactions between the polypyrrole’s π-conjugated structure and the d-electrons of copper, promoting orbital hybridization that facilitates efficient electron delocalization and charge transfer at the electrode–electrolyte interface. X-ray diffraction confirms the presence of a crystalline face-centered cubic (FCC) copper phase embedded within the polymer matrix, while scanning electron microscopy reveals a porous architecture that is conducive to electrolyte infiltration. Electrochemical analyses, including chronoamperometry, cyclic voltammetry, and electrochemical impedance spectroscopy, indicate a notable decrease in charge transfer resistance (1.6 Ω) and a substantial increase in cathodic current density (8.38 mA cm−2), reflecting improved redox kinetics. The x-ray photoelectron spectroscopy (XPS) results confirm the successful integration of copper with polypyrrole, showing distinct Cu2+ species and nitrogen bonding environments that support interfacial electronic coupling consistent with π–d orbital interaction. When incorporated into a DSSC using methyl orange as the sensitizing dye, the Cu0.2PPy CE delivered power conversion efficiency of 4.84%, rivaling traditional platinum-based electrodes. This excellent performance arises from the combined effects of orbital-level electronic synergy and nanoscale porosity, which collectively enhance interfacial charge mobility and catalytic accessibility. This work illustrates how rational design of hybrid materials at the molecular orbital level can yield high-performance, scalable alternatives to precious metals in solar energy devices.

Graphical Abstract