China dominates the discovery of new chemicals and reactions

China now discovers more than 40% of new chemicals and reactions reported in scientific literature, with the country’s contributions growing exponentially in recent decades, according to a new report. The researchers behind the work attribute this to China’s investment in its chemical sector, which has enabled the country to overtake the US as the dominant leader in chemical discovery. The report also challenges the idea that China’s progress in the chemical sciences is due to its collaborations with US scientists.

In recent years, China has solidified its position as a powerhouse of scientific research. For example, the Nature Index ranking for the applied sciences shows that Chinese researchers produced more than half of the research output published in top quality journals in 2024. The top ten institutions – in terms of the number of high-quality applied science research articles authored by their researchers – were all based in China.

‘China has focused a lot on applied sciences in order to contribute to their industrial base,’ says Caroline Wagner, a science policy expert at Ohio State University in the US, who was not involved in the new analysis. ‘The question I think, for China and for all of us, is can China do basic research that underlies how a field moves forward.’

To help probe this, a team led by Guillermo Restrepo from the Max Planck Institute for Mathematics in the Sciences in Germany has now investigated how known chemical space – the collection of all reported substances and reactions – has changed over time. The researchers analysed data covering the period from 1996 and 2022 from the chemical database Reaxys and open access libraries Dimensions and OpenAlex.

A changing chemical space

Restrepo’s analysis shows that the known chemical space continues to grow steadily by around 4% per year, a trend that has been consistent over the past 200 years.

‘We [also] found that at the very beginning of [the 1990s], the US was contributing more or less a quarter of the new discoveries in the chemical space, whereas for China it was less than 1%,’ explains Restrepo. ‘Today, China is contributing 41% to the chemical space, whereas the US is 11%.’

The team also explored how the chemical space has changed in three key areas: organics, organometallics and rare-earth elements.

China now accounts for 40% of the discoveries of new organic compounds, an area that covers the vast majority of known chemical space. The researchers suggest this is in large part due to R&D initiatives and regulatory reforms in the 2000s that accelerated the growth of the country’s pharmaceutical sector.

Since 2004, China has also dominated the discovery of materials based on rare earths, and now contributes 40% of the new substances in this category that are reported each year. ‘China not only owns the ores [containing rare-earth elements], they are also the top country in the production of new substances containing rare earths,’ notes Restrepo.

While China is the top discoverer of new organometallic compounds (17%), the US (10%), Germany (9%) and India (7%) are also major contributors. Restrepo’s team says that China’s delayed expansion in this area likely stems from the country’s earlier focus on pharmaceuticals or agrochemicals, which prioritised traditional organic chemistry research.

Restrepo’s team notes that China’s growth in the chemical space ‘has been driven primarily by its own domestic efforts rather than international partnerships’.

Further illustrating China’s focus on building its domestic science base, a recent analysis by the American Association for the Advancement of Science (AAAS) found that since 2005, China has consistently employed more researchers than the US. New analysis from the Organisation for Economic Co-operation and Development (OECD) also shows that in 2024, China outspent the US on research for the first time, when figures are adjusted to take into account local purchasing power. According to the OECD’s analysis, China’s government and businesses spent an equivalent of $1.03 trillion (£760 billion) on research – around 2.7% of the country’s GDP – compared to the US’s $1.01 trillion (3.4% of GDP). The study also found that China’s investment in the sector is growing at a rate of more than 14% per year.

Economic influences

Restrepo and his team also highlight how key economic events impacted the US and China’s research output in different ways. For example, the 2008 financial crash marked the start of the US’s decline in contributions to known chemical space, while China’s chemistry research was unaffected by the event.

However, the Covid-19 pandemic and rapid lockdowns caused China’s contributions to the chemical space to fluctuate. This doesn’t appear to have been the case in the US, with Restrepo suggesting that this was due to President Trump’s more relaxed approach to the pandemic. ‘You can see how these political decisions are affecting the expansion of chemistry,’ he adds. ‘The expansion of science, and in particular the chemical space, is very sensitive to the political situation and economics.’

According to Restrepo, the Trump administration’s 2018 China Initiative – which aimed to curb the perceived threat of academic collaboration with China – fed a narrative that Chinese scientists depend on US researchers. However, he notes that the team found that more than 90% of China’s contribution to the chemical space happens without collaborating with any other countries.

As for the US, less than 80% of its contribution to the chemical space is due to solo discoveries, down from 95% in 1996. Analysis revealed that the US now increasingly collaborates with other countries – notably China in particular.

‘I wouldn’t look at it as a zero-sum game,’ says Wagner. ‘The extent to which China practises openness in science – they’re contributing to what we know, and we can all benefit from it.’

What’s next?

Restrepo and his team have now released an interactive dataset to help chemists explore trends related to their own research field or country.

Since the dataset only goes up until 2022, Restrepo cautions that we need to wait a couple of years to see the effects of, for example, trade tariffs enacted during Trump’s second presidency. He expects some volatility in the chemical space, in particular with rare-earth elements, with these substances playing important roles in technologies that have been affected by the tariffs, including in renewable energy, medical imaging and many electronic devices.

According to Wagner, the loss of the US’s dominant position in chemistry research could ‘encourage a competitive spirit’. ‘If [China is] where smart people are working, we should be working with them,’ she notes. ‘But that doesn’t always work out on the geopolitical level.’