Hydrogen, the smallest element, easily forms bonds to host/dopant atoms in semiconductors, which strongly passivates the original electronic characteristics and deteriorates the final reliability. Here, we demonstrate a concept of unidirectional elimination of hydrogen from semiconductor wafers as well as electronic chips through a giant local electric field induced by compact chloridions. We reveal an interactive behavior of chloridions, which can rapidly approach and take hydrogen atoms away from the device surface. A universal and simple technique based on a solution-mediated three-electrode system achieves efficient hydrogen elimination from various semiconductor wafers (p-GaN, p-AlGaN, SiC, and AlInP) and also complete light emitting diodes (LEDs). The p-type conductivity and light output efficiency of H-eliminated UVC LEDs have been significantly enhanced, and the lifetime is almost doubled. Moreover, we confirm that under a one-second irradiation of UVC LEDs, bacteria and COVID-19 coronavirus can be completely killed (>99.93%). This technology will accelerate the further development of the semiconductor-based electronic industry.