From 2016 through 2020, blockchain research in smart cities was exploratory and often siloed. By 2023, a surge in publications on security, mobility, and governance marked a transition to integrated, sector-specific deployments. While research output appeared to decline in 2025, the authors attribute this to partial data for the year. Importantly, the study emphasizes that blockchain is more than a technical layer, it is also an ethical infrastructure that s
A new study titled “Blockchain and Smart Cities: Co-Word Analysis and BERTopic Modeling” published in Smart Cities delivers the most comprehensive thematic and technological mapping of blockchain research in urban environments to date. Through a combination of co-word analysis and advanced BERTopic modeling, the authors uncover how blockchain is evolving from foundational infrastructure to sector-specific innovation engine across transportation, energy, waste, healthcare, and governance.
The analysis of 576 peer-reviewed journal articles from 2016 to 2025 reveals a distinct shift: early generalist discussions of blockchain’s potential have matured into targeted applications in decentralized energy trading, drone coordination, real-time healthcare, and privacy-preserving smart infrastructure. The study positions blockchain not just as a technical enabler, but as a socio-ethical scaffold supporting the transition toward resilient, secure, and sustainable smart city ecosystems.
The study identifies five dominant thematic clusters that define the current state of blockchain integration into urban systems. Blockchain plays a foundational role in creating secure, decentralized, and interoperable infrastructure through technologies such as IoT, edge computing, and smart contracts. This cluster highlights the use of blockchain in authenticating data, protecting privacy, and mitigating cybersecurity threats across sensor-driven city functions.
A second theme is the convergence of blockchain with AI and machine learning to enable intelligent sustainability. Applications in decentralized energy systems, including peer-to-peer (P2P) energy trading, prosumer-led microgrids, and real-time energy optimization, reflect blockchain’s role in democratizing and greening urban power flows. Additional intersections with digital twins, predictive mobility, and urban health monitoring demonstrate the technology’s reach.
The third cluster centers on decentralized mobility solutions. Blockchain supports secure vehicle-to-everything (V2X) communications, federated learning models for autonomous systems, and trusted drone swarms for logistics and surveillance. Keywords such as “ITS,” “Internet of Vehicles,” and “Edge Computing” point to blockchain’s growing presence in connected transport infrastructure.
Two more clusters address emerging applications in smart homes and public services. In residential settings, blockchain underpins trusted interactions between electric vehicles, solar panels, and household energy networks, often using consortium blockchains like Hyperledger Fabric. In healthcare and waste management, blockchain is being deployed for e-health records, pandemic tracking, e-waste transparency, and circular economy goals. These applications point to blockchain’s evolution from a generalized concept to a deeply embedded infrastructure across urban life.
Using BERTopic modeling, the study identifies seven high-coherence topics that signal the near-future direction of research and development. The largest cluster, accounting for nearly 25% of all reviewed literature, focuses on blockchain-driven security and privacy solutions for IoT-enabled smart cities. This includes decentralized identity management, secure device authentication, and hybrid AI-blockchain models for threat detection.
Another major topic addresses the strategic, institutional, and regulatory dimensions of blockchain adoption. Research highlights how national strategies (such as Dubai’s Blockchain Strategy) and pilot programs are shaping frameworks for digital governance, public sector transformation, and urban service delivery.
Mobility remains a prominent focus. Blockchain supports trusted communications in vehicular networks, decentralized parking systems, traffic optimization, and drone logistics. AI-enhanced, privacy-preserving models, especially federated learning and digital twin integration, are paving the way for self-organizing and autonomous transport ecosystems.
In energy, blockchain enables decentralized trading platforms, secure smart grid operations, and automated auction protocols for prosumers. Pioneering studies introduce lightweight consensus mechanisms and tokenized “energy tags” to foster market transparency and cost efficiency.
Other emerging clusters include blockchain-enabled healthcare platforms for urban health resilience, blockchain-driven waste governance systems using smart contracts and predictive analytics, and security frameworks for drone ecosystems, collectively referred to as the Internet of Drones (IoD). These topics reinforce the view that blockchain is increasingly central to sectoral digital transformation strategies.
The study’s longitudinal analysis reveals a significant temporal shift. From 2016 through 2020, blockchain research in smart cities was exploratory and often siloed. By 2023, a surge in publications on security, mobility, and governance marked a transition to integrated, sector-specific deployments. While research output appeared to decline in 2025, the authors attribute this to partial data for the year.
Importantly, the study emphasizes that blockchain is more than a technical layer, it is also an ethical infrastructure that supports transparency, citizen-centric design, and resilience. Use cases such as blockchain-based e-voting, public service authentication, and decentralized data ownership illustrate its role in reinforcing trust and digital sovereignty in smart urban settings.
The paper calls for future research in scalable architecture, energy-efficient consensus models, and integrated platforms combining AI, IoT, and blockchain. Researchers also urge deeper exploration into governance frameworks that ensure ethical, equitable, and transparent blockchain applications, especially in areas like health data, resource tracking, and autonomous mobility.
