Spatiotemporal dynamics and topological connectivity of the global platinum group metals trade network: a multiscale network perspective

Platinum group metals (PGMs) are critical raw materials for diverse industries, including automotive, chemical, electronics, and hydrogen energy sectors. Research on the spatiotemporal evolution of global PGMs trade networks is essential for understanding global supply-demand dynamics and supply chain systems. This study constructs a comprehensive long-term dataset of the global PGMs trade networks and employs advanced network analysis methods to characterize their spatiotemporal evolution and topological structures. The findings include: (1) Since 2001, both the trade value and volume of global PGMs have exhibited fluctuating growth trends, notably responsive to international events such as financial crises and the COVID-19 pandemic. (2) The overall structure of the global PGMs trade network has remained stable, with continual growth in trade scale and network density, showing clear hierarchical and spatial imbalances. This structure features South Africa and Russia at its core, surrounded by major trade groups in Europe-America and Asia. (3) At the macro level, the connectivity of the global PGMs trade network has significantly improved, reflected in fluctuating trends in network clustering and transmission efficiency. At the meso level, the backbone structures have continuously expanded, demonstrating a multi-centralized nature. At the micro level, South Africa and Russia emerge as influential global PGMs exporters, while the United States, Germany, the United Kingdom, Switzerland, Italy, Japan, and others maintain core positions. China is progressively becoming a pivotal trade hub in Asia and globally. Building on these findings, this paper proposes policy recommendations to enhance international trade cooperation in PGMs and ensure supply security.