Controlling the insertion of defects on large-area MoS2 layers by electrochemical and chemical processes

• Grant number: 25/04673-7
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: September 15, 2025
• End date: September 14, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Murilo Santhiago
• Grantee: Matheus Felipe Fagundes das Neves
• Supervisor: Jonathan Nesbitt Coleman
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Institution abroad: Trinity College Dublin, Ireland
• Associated to the scholarship: 23/15689-6 - Evaluation of the impact of defect insertion on the electrical and electrochemical properties in monolayers of MoS2., BP.PD

Abstract

The introduction of defects into the basal plane of molybdenum disulfide (MoS2) has been widely recognized as a method to enhance its electrocatalytic performance. However, a comprehensive correlation between defect density and electrical properties remains underexplored. This relationship is particularly relevant, as defects, while detrimental to the functionality of electronic devices serve as necessary active sites for the Hydrogen Evolution Reaction (HER). The project seeks to overcome this gap by developing controlled exfoliation techniques, enabling precise manipulation of defect insertion in high-aspect-ratio MoS2 monolayers. The goal is to produce large-area defective MoS2 layers and precisely correlate its electrochemical and electrical characteristics. Liquid exfoliation will be employed, aided by layer intercalation, ensuring that unintentional defects and carbon contamination are minimized. Control over defect insertion will be achieved by adjusting the concentration and exposure time of an oxidizing agent to facilitate exfoliation and structural modifications. Subsequently, an in-depth characterization encompassing morphological, optical, structural, and electrical properties will be performed. As outlined in the post-doctoral research proposal for Research Internships Abroad (BEPE), these characteristics will be examined by combining expertise in advanced fabrication, electrochemistry, and electric device characterization.