The multiplex network structure of global cobalt industry chain

During the transition of energy system to clean energy, energy security challenges shift from crude oil to critical minerals such as cobalt. Understanding the global cobalt industry chain thus has become a new challenge in the coming era of clean energy. In this study, we construct a multiplex network model and analyze the multiplex structure features of the global cobalt industry chain, which are our main innovations. Results show that (1) trade complexity in upstream network is the lowest compared with middle-stream network and downstream network; (2) most economies only participate in one or two stages of cobalt industry chain, while a few economies participate in the whole chain and own the global influences; (3) Mainland of China, USA, Germany, United Kingdom, and Spain are the systemic importance nodes for the global cobalt industry chain. These results provide a knowledge base for future studies on the cascading failure of supply crisis in the multiplex network of the global cobalt industry chain.