A method is provided for making a lithium-sodium-antimony photocathode including the step of forming a base layer including antimony on a substrate. Sodium is then deposited onto the base layer at an elevated temperature to a first peak value of responsivity, thereby forming a sodium-antimony surface. Next, at room temperature, lithium is deposited onto the substrate containing the sodium-antimony surface until the lithium-sodium-antimony photocathode develops a hazy brown color. The photocathode is sensitized by heating the substrate to an elevated temperature until a second peak value of responsivity, greater than the first peak value, is obtained. Antimony, sodium and lithium are then alternately deposited on the photocathode in order to stabilize the second responsivity peak.