Application of ZIF-67 based nitrogen-rich carbon frame with embedded Cu and Co bimetallic particles in QDSSCs. (1st May 2022)

• Record Type: Journal Article
• Authors: Liu, Shuang'an; Wang, Senyang; Cao, Ying; Liang, Chengyang; Geng, Shitong; Guo, Haipeng; Liu, Ying; Zhang, Wenming; Li, Ling
• Is Part Of: Solar energy. Volume 237(2022)
• Page Start: 144
• Page End: 152
• Publication Date: 2022-05-01
• Subjects: Quantum dot sensitized-solar cells -- Counter electrode -- ZIF-67 -- Transition metal; Solar energy -- Periodicals; Solar engines -- Periodicals; 621.47
• DOI: 10.1016/j.solener.2022.04.004
• Languages: English
• ISSNs: 0038-092X

Abstract

Graphical abstract: A carbon polyhedral composite Cu/Co@NCF coated with copper and cobalt metal particles was prepared conveniently and applied as CE via silk screen method. The concave and rough surface and porous structure of Cu/Co@NCF provide sufficient catalytic activity sites, and the encapsulated Cu and Co particles greatly promote the effective enhancement of catalytic activity. With a series of film thickness optimization, Cu/Co@NCF CE of 16 μm thickness shows excellent electrocatalytic performance, contributing to the realization of the photoelectric conversion efficiency of 6.66%, apparently higher than that of Co@NCF CE without Cu-doped (5.27%), and effectively close to that of common Cu2 S/Cu CE(7.29%), providing a novel exploration for QDSSCs CE application materials. Highlights: Cu and Co metal particles were successfully doped into ZIF-67 based carbon polyhedra by hydrothermal and synchronous doping methods to form Cu/Co@NCF composites. The concave and rough polyhedral morphology and the rich doping of N element make Cu/Co@NCF porous and of a large specific surface area. The sufficient and uniform distribution of transition metals Cu and Co greatly improves the electrocatalytic performance of the composites. The PCE of QDSSCs using Cu/Co@NCF CE after optimizing the film thickness (16 μm) reaches 6.66% remarkably. Abstract: The catalytic enhancement of counter electrode materials is of an essential move for the overall evolution of QDSSCs. While the commonly used Cu2 S/Cu counter electrode is easy to be eroded off by sulfur electrolyte, resulting in photoanode pollution. Herein, rough polyhedron Cu/Co@NCF composite is smoothly prepared via hydrothermal and synchronous doping method to replace Cu2 S/Cu application. With the ZIF-67 as carbon source and morphology support, Cu and Co nanoparticles (NPs) are uniformly embedded in the carbon polyhedron without agglomeration, while the doping of nitrogen makes the composites have better porous structure. Combining the superior catalytic from Cu and Co particles with the electrical conductivity and stability from the carbon frame, the Cu/Co@NCF composite as QDSSCs counter electrode achieves an excellent photoelectric conversion effect (6.66%), close to that of Cu2 S/Cu (7.29%). With stable and excellent counter electrode performance, Cu/Co@NCF composite unquestionably has the potential to be an alternative material for the CE application of QDSSCs.