TOKYO -- China dominates a global ranking of the most-cited research papers published in the 30 hottest technology fields, a development likely to alarm American leadership already leery of its rising Asian rival.

Though the U.S. accounted for 3.9 million research papers overall compared with 2.9 million from China, the Asian country produced the largest share in 23 of the 30 fields that drew the most interest, while America took the crown for the remaining seven.

Nikkei and Elsevier compiled the ranking based on 2013-18 data provided by the Dutch publisher, covering a total of 17.2 million papers.

Materials known as perovskites, used to make highly efficient solar cells, topped the list of these 30 fields, followed by monatomic layers that are expected to lead to faster and more energy efficient semiconductors. Sodium-ion batteries that are seen providing a low-cost source of power ranked third.

China led the world in the majority of the top 10 fields, and each of the five areas in the top 10 tied to battery research. It accounted for more than 70% of all papers on photocatalysts and nucleic-acid-targeted cancer treatment, which ranked 12th and 14th. The U.S. led in three biotechnology fields, including No. 7 genome editing and No. 10 immunotherapy.

China was previously noted for the sheer volume of its research papers, but the quality of the research has improved in recent years. It accounted for nearly 11% of the papers that made the biggest impact, based on such factors as the number of citations, between 2014 and 2016.

The country's rise in technology research follows a sharp increase in R&D investment. China more than tripled spending on research and development between 2010 and 2016.

China's domestic R&D investment totaled $410 billion in 2016, not far behind the $464 billion of the U.S., data from the Organization for Economic Cooperation and Development shows. In 2017, 510,000 Chinese papers were published in scientific journals, representing a 27% increase in five years, according to Elsevier. While America remained ahead with 560,000, its output was nearly flat over that period.

The U.S., which has dominated cutting-edge research for decades, is deeply suspicious of China's growing presence. President Donald Trump has repeatedly criticized Beijing's "Made in China 2025" initiative to advance domestic industry as American concerns over the country's ascent in technology research exacerbate the current trade war.

More than the U.S. or Japan, China has focused its investment in areas with commercial potential, with a particular focus on material science for applications in electronics and electric vehicles, Elsevier said.

Beijing is targeting 10 core fields in its Made in China 2025 campaign. By improving its research and development process, China aims to become a manufacturing power in 2025 and a world-class producer in 2049. The core fields for Made in China 2025 can be seen in the list of research topics the country dominates in the ranking.

Although China is considered the world's factory for its production of goods like home electronics and cars, the U.S., Europe and Japan are still considered to have the lead in key technologies. "China is concentrating investment in research for high-tech industries so that it can also become self-reliant in fields for which it heavily relies on imports," said Naoto Saito at the Daiwa Institute of Research.

The U.S. has responded by taking steps against emerging companies closely linked to Made in China 2025, such as telecommunications equipment makers Huawei and ZTE. Tensions between the countries will intensify should the U.S. grow concerned that China will dominate research fields that are likely to be commercialized in five to 10 years.

Meanwhile, Japan lags behind both countries with less than a 10% share of papers in nearly all of the top 30 fields. It 2016 R&D spending came to 18.4 trillion yen ($170 billion at current rates), well under half the American and Chinese totals. The government covered 17.4% of this spending, compared with more than 20% in the U.S. and China.