Necip Ali Tuna , Adem Mutlu , I. Isil Gurten Inal , Esra Yıldız
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引用次数: 0
Abstract
This study explores the feasibility of heteroatom-doped activated carbon (Ac) as a low-cost substitute for platinum (Pt) counter electrode (CE) in dye-sensitized solar cells (DSSCs). Ac was doped with nitrogen (N), sulfur (S), and phosphorus (P), both individually and in combination (S-N-P), to examine their effects on Ac structure, electrochemical behavior, and DSSC performance. Scanning electron microscopy (SEM) demonstrated notable micromorphological changes due to doping, influencing porous structure and surface uniformity. While undoped Ac exhibited a rough and irregular microstructure, N-doping reduced surface roughness and irregularity, leading to a more ordered porous structure. However, it also increased charge transfer resistance due to the formation of larger pores, ultimately resulting in lower efficiency. P-doping introduced structural disorder, further elevating charge transfer resistance and shortening electron lifetime, resulting in the lowest DSSC power conversion efficiency (PCE) of 0.9 %. In contrast, S-doping produced a more compact structure with enhanced electrocatalytic activity, improving PCE (3.2 %). The best performance was observed in S-N-P co-doped Ac, which achieved a PCE of 5.0 %, approaching that of Pt (6.6 %), due to reduced charge transfer resistance (R1 = 6.5 Ω). Electrochemical impedance spectroscopy (EIS) confirmed that lower charge transfer resistance correlates with higher DSSC performance. Raman and XPS analyses further supported this result by confirming balanced defect density and rich surface functionalization in the S-N-P co-doped Ac. The research demonstrates the potential of multi-heteroatom doping of Ac for developing scalable, sustainable, and environmentally friendly alternatives to platinum for DSSC applications.
期刊介绍:
Dyes and Pigments covers the scientific and technical aspects of the chemistry and physics of dyes, pigments and their intermediates. Emphasis is placed on the properties of the colouring matters themselves rather than on their applications or the system in which they may be applied.
Thus the journal accepts research and review papers on the synthesis of dyes, pigments and intermediates, their physical or chemical properties, e.g. spectroscopic, surface, solution or solid state characteristics, the physical aspects of their preparation, e.g. precipitation, nucleation and growth, crystal formation, liquid crystalline characteristics, their photochemical, ecological or biological properties and the relationship between colour and chemical constitution. However, papers are considered which deal with the more fundamental aspects of colourant application and of the interactions of colourants with substrates or media.
The journal will interest a wide variety of workers in a range of disciplines whose work involves dyes, pigments and their intermediates, and provides a platform for investigators with common interests but diverse fields of activity such as cosmetics, reprographics, dye and pigment synthesis, medical research, polymers, etc.