Disclosed herein are metal oxides, metal oxide surfaces, and methods of using metal oxides and metal oxide surfaces for matrix-free analysis, identification, and characterization of small molecular mass compounds. The disclosed compounds and methods may be used with laser desorption/ionization-mass spectrometry. The disclosed surfaces may aid in producing mass/charge spectra having low or no interference found with traditional matrices. In some aspects, the method may be used to produce molecular ions. The disclosed compounds, surfaces, and methods may be used to analyze complex mixtures including fuels, vegetable shortening, lipid extracts from a variety of organic sources such as animals, plants, bacteria, algae, viruses, etc.