1 A review on bimetallic composites and compounds for solar cell applications 1 The scientific community has developed new technologies, including solar cells (SCs), to meet global energy demands. SCs convert solar energy into electrical energy, providing renewable, sustainable, and green energy. Despite the availability of PV systems for many years, power generation through SC technology remains costly due to the low conversion efficiency (CE). Their low CE is due to limitations in semiconducting materials. In the present review, the basic mechanism of SC and techniques for modify SC have been discussed. The main focus of this review is to given an overview about the bimetallic materials and their application in SC. Bimetallic materials consist of two metallic components that can be synthesized using different methods. They exhibit exceptional properties, including improved electrical conductivity, tunable electrochemical activity, and high charge capacity compared to monometallic materials, making them promising candidates for use as electrochemical catalysts and photocatalysts. Various types of bimetallic composites and compounds, such as, oxides, phosphide, sulfide and carbon-based bimetallic composites is explained in the context of their compositions, synthesis techniques and their power generation efficiency. In the last portion of review, the importance of bimetallic materials in SC appli-cation with their possible promising research direction and challenges are presented. 91 101 Leila Bazli School of Science and Technology, University of Georgia, Tbilisi Georgia leilabazli64@gmail.com Fariborz Sharifianjazi School of Science and Technology, University of Georgia, Tbilisi Georgia f.sharifianjazi@ug.edu.ge Amirhossein Esmaeilkhanian Department of Materials and Metallurgical Engineering, Amirkabir University of Technology, Tehran Iran esmaeilkhanian.a@gmail.com Maryam Nili Ahmadababdi Materials Engineering Department, Tarbiat Modares University, Tehran Iran M_nili@modares.ac.ir Bahman Amini Horri School of Mechanical Engineering Sciences, University of Surrey, Guildford, Surrey GU2 7XH UK b.aminihorri@surrey.ac.uk Ashish Ravalia Department of Nanoscience and Advanced Materials,Saurashtra University, Rajkot 360005 India Safiyeh Mohammadi Sciences Faculty, Zanjan University, Zanjan Iran Safiyehmohammadi61@gmail.com Abdurrahman Yolun Physics Department, Inonu University, 44280 Malatya Turkey Kyusun Kim Department of Nano Engineering, Department of Nano Science and Technology, SKKU Advanced Institute of Nanotechnology(SAINT), Sungkyunkwan University(SKKU),Suwon Republic of Korea il.jeon@spc.oxon.org Maryam Azimpour Hospital of Shahid Ayatollah Dastgheib, Shiraz University of Medical Science, Shiraz Iran m.azimpoor62@gmail.com Shwetha Rani R Centre for Nano and Material Sciences, Jain University, Jain Global Campus, Kanakapura, Bangalore 562112 Karnataka India Solar cells Bimetallic Composites Compounds Solar energy Article4.pdf [1] J.-S. 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