Davy conducted research on agricultural chemistry, studying the composition of soils and the nutritional requirements of plants. His lectures on agricultural chemistry were popular and influential, promoting the application of scientific principles to farming.

Davy had a strong interest in geology and conducted geological investigations in Cornwall and other regions. He studied the formation of rocks, the distribution of minerals, and the processes of erosion and sedimentation.

Davy investigated the properties of metals and alloys, seeking to develop improved materials for various applications. He studied the effects of alloying elements on the strength, ductility, and corrosion resistance of metals. He performed some early experiments on platinum.

Davy was interested in the conservation of paintings and conducted research on the chemical processes that cause the deterioration of pigments and varnishes. He developed methods for cleaning and preserving old paintings.

Davy analyzed ancient materials from archaeological sites, seeking to understand the technologies and materials used by ancient civilizations. He studied pigments from Egyptian tombs and analyzed the composition of Roman bronze artifacts.