Invention profiles and uneven growth in the field of emerging nano-energy

This paper aims to synthetically investigate invention profiles and uneven growth of technological knowledge in the emerging nano-energy field, based on patents data extracted from the Derwent Innovation Index (DII) database during the time period 1991–2012. The trend analysis shows that invention in this field has experienced enormous growth and also diversification over the past 22 years. The co-occurrence network of burst technology domains reveals that technology domains constantly burst, and innovative progress in nanotechnology has tremendously contributed to energy production, storage, conversion and harvesting and so on. Nano-energy patented inventions mainly come from a combinatorial process with a very limited role of developing brand-new technological capabilities. Reusing existing technological capabilities including recombination reuse, recombination creation and single reuse is the primary source of inventions. For the impacts of technology networks' embeddedness, we find that network tie strength suppresses the growth of technological knowledge domains, and network status and convergence both facilitate the growth of technological knowledge domains. We expect that this study will provide some enlightenment for inventing or creating new knowledge in emerging fields in complex technological environment.