TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The growing the array of two-element nanowires further involves: uniformly varying a characteristic of each two-element nanowire, where the characteristic is at least one of physical dimension, processing time, temperature, packing density, energy band-gap, and composition of each two-element nanowire; seeded growing of the array of two-element nanowires; and performing a hydrothermal or solvothermal synthesis. The uniformly doping or alloying each two-element nanowire further involves: uniformly controlling a concentration and band-gap of each at least three-element nanowire by varying a fabrication parameter selected from temperature, processing time, pH and pressure; or uniformly controlling a concentration of each element of each at least three-element nanowire. The wet chemical synthesis is a hydrothermal or solvothermal synthesis performed at less than 300 degrees C. The hydrothermal or solvothermal synthesis is performed at 100-200 degrees C. The uniformly doping or alloying each two-element nanowire is performed by uniformly doping or alloying each two-element nanowire with the doping or alloying element with respect to a radial cross section of each two-element nanowire. The method (M1), (M2) or the system further involves: annealing the uniform nanowire array of at least three-element nanowires performed at 200-1000 degrees C for 5 minutes to 10 hours. The heating is performed at less than 300 (preferably 100-200) degrees C. Preferred Components: When the two-element nanowire comprises Zn and O; Cu and O; Cd and O; Mg and O; Fe and O; Be and O; Mn and O; then the doping or alloying element or at least third element is at least one of Mg, Cd, Mn, Cu, Be, Fe or Co; Zn, Mg, Cd, Be, Fe, or Co; Mg, Zn, Mn, Cu, Be, Fe, or Co; Zn, Cd, Mn, Cu, Be, Fe, or Co; Zn, Cd, Mn, Cu, Mg, Be or Co; Zn, Cd, Mn, Cu, Fe, Mg or Co; Zn, Cd, Cu, Fe, Mg, Be or Co respectively. The first module further comprises uniformly varying a characteristic of each two-element nanowire, where the characteristic being at least one of physical dimensions, processing time, temperature, packing density, energy band-gap, and composition of each two-element nanowire; a seeded growing of the array of two-element nanowires; hydrothermal or solvothermal synthesis module. The uniform composition distribution or uniformity is achieved by controlling a concentration and band-gap of each at least three-element nanowire by varying a fabrication parameter selected from temperature, processing time, pH and pressure; or is achieved by controlling a concentration of each element of each at least three-element nanowire. The uniform composition distribution is achieved by uniformly doping or alloying each two-element nanowire with the doping or alloying element with respect to a radial cross section of each two-element nanowire. In the uniform nanowire array (A1), at least three-elements include Zn, O, and Mg; Zn and O and at least one of Mg, Cd, Mn, Be, Fe, and Co; Cu and O and at least one of Zn, Mg, Cd, Be, Fe, Mn, and Co; Cd and O and at least one of Mg, Zn, Mn, Cu, Be, Fe, and Co; Mg and O and at least one of Zn, Cd, Mn, Cu, Be, Fe, and Co; Fe and O and at least one of a Zn, Cd, Mn, Cu, Mg, Be, and Co; Be and O and at least one of Zn, Cd, Mn, Cu, Fe, Mg, and Co; or Mn and O and at least one of Zn, Cd, Cu, Fe, Mg, Be, and Co. In the solar cell device or electronic device, the elements include Zn, O and Mg.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Device: The electronic device further comprises leads configured to carry electrons to or from the junction to enable the electronic device to convert electrons to photons or photons to electrons.