Finally I found a 6060 SMD UV-C LED with a radiant flux of 100mW @350mA and 6V, 275nm, named S6060-W275-P100-MH, datasheet can be found at the FILES section. Disadvantage is however the short life time, typically 1000 to 3000 h, depending on power output.
I spent two days to design a new high power UV-C LED driver, based on the LT1618. The width of the PCB is exactly the same as of the TO220, so I can use TO220-heat sinks. I added two mounting holes to attach two 25mm long TO220-heat sinks. The left cutout is for a push button, so the UV-C LED module will only turn on if it is correctly inserted in the disinfection chamber. The right cutout is for a status LED.
My favorite PCB fab Aisler will support me on my COVID-19 projects and provide PCBs and stencils free of charge. Thanks again, Felix!
Three of the 100mW UV-C LEDs, 30€ each:
Suitable heatsink samples: