Near infrared to visible up-conversion devices have every growing demand in a myriad of industrial sectors including photovoltaics, energy harvesting, medicine and imaging. Here we have demonstrated an up-conversion device which utilizes quantum dots for both infrared absorption and visible emission. The band structure of the device is designed and optimized with well-constructed carrier transport and blocking layers. The achieved up-conversion device exhibits an impressive conversion efficiency of over 6 %, with a high near infrared on-off ratio of over 104. The device demonstrates a potential new approach for an up-conversion device designed solely on quantum dots with high efficiency.
