The Silk Road offers a wealth of sub-topics for a research paper dealing with Chinese history. One particular aspect of the silk road is that the Chinese were early experts in the division of labor. Centuries before Henry Ford's assembly line, Chinese artisans divided their expertise into varying aspects of the manufacture and delivery of silk.
The British East India Company blew its monopoly on British trade with China in the 1830s and this gave way to the Opium Wars. In 1836, opium was banned by the Chinese government, and it began to crack down on opium dens while executing Chinese opium dealers. The history of the Opium Wars is fertile ground for a fascinating research paper, as there are certain similarities with contemporary drug wars to compare them with.
Arguments exist as to whether China should be credited---or blamed---as the country where gunpowder was created. This lack of a formal answer to the question creates plenty of opportunity for research to determine whether China actually did precede Roger Bacon in the invention of gunpowder by two centuries.
Confucius has become the punchline of bad jokes in the Western world, but K'ung Fu Tzu really did exist, and his philosophy guided Chinese people for centuries. A research paper on Confucian philosophy can be more than just a learning experience. The research paper can take the path of exploring the history of the man or the history of the philosophy.
Legalism was a doctrine that stood in opposition to Confucianism's morality as a guiding philosophy. Legalism eschewed moral theoretical ideas in favor of harsh laws and punishment to guide citizens. A research paper can examine the effects of Legalism, especially as it was applied during the powerful Qin Dynasty.