Integrating Blockchain with IoT and AI: Toward a Secure and Intelligent Future

The convergence of Blockchain, Internet of Things (IoT), and Artificial Intelligence (AI) represents a transformative evolution in the digital era. This integration promises to reshape industries by enabling decentralized, intelligent, and secure systems. Blockchain provides a robust foundation for data integrity and trust, while IoT enables seamless interconnectivity of devices, and AI offers capabilities for autonomous decision-making and predictive analytics. This review paper explores the synergistic integration of these technologies, highlighting the benefits, use cases, current research trends, and associated challenges. It also identifies potential research directions to guide future developments. The paper aims to provide a comprehensive understanding of how the fusion of Blockchain, IoT, and AI can drive innovation in sectors like healthcare, smart cities, supply chain, and finance while ensuring security, transparency, and efficiency. Through a synthesis of contemporary literature, this paper also delves into the role of emerging paradigms like federated learning, decentralized edge computing, and token economies, offering a forward-looking perspective on the secure and intelligent future enabled by technological convergence.