Photocatalytic Hydrogen Production over CdS Nanomaterials: An Interdisciplinary Experiment for Introducing Undergraduate Students to Photocatalysis and Analytical Chemistry

Photocatalytic hydrogen generation over semiconductor photocatalysts has attracted considerable attention over the past few decades. This experiment is designed for sophomore- and higher-level undergraduates who are in the majors of materials chemistry, analytical chemistry, catalysis, or chemical engineering. In this experiment, CdS nanoparticles and nanosheets were first fabricated with a one-step direct-precipitation reaction and a two-step precipitation–ion-exchange reaction, respectively, and then used as photocatalysts for visible-light hydrogen evolution from water, in the presence of noble-metal Pt nanoparticles as in situ cocatalysts and sodium sulfide and sulfite (Na2S/Na2SO3) as sacrificial reagents. A gas chromatograph with a thermal-conductivity detector (GC-TCD) was used to quantitatively monitor the produced hydrogen gas. This interdisciplinary experiment is expected to give students an introduction to nanomaterial synthesis, the general process of photocatalytic hydrogen generation, and th...