Efficient, Ambient‐Stable, All‐Polymer Organic Photodetector for Machine Learning‐Promoted Intelligent Monitoring of Indoor Plant Growth
Bing‐Huang Jiang, Di‐Wen Lin, Ming‐Neng Shiu, Yu‐Wei Su, Tsung‐Han Tsai, Pei‐Hsun Tsai, Tien‐Shou Shieh, Choon Kit Chan, Jong‐Hong Lu, Chih‐Ping Chen
Abstract
Abstract The blend ratio and thickness of the PM6:PY‐IT active layer are optimized to realize highly efficient all‐polymer organic photodetectors (OPDs). Ultralow dark current densities of less than 5.92 × 10 −10 A cm −2 (at −1 V) appear when the PM6:PY‐IT active layers have thicknesses in the range of 250–400 nm and blend ratios between 1:1 and 1:1.4, suggesting a wide fabrication window. Fast rise/fall times of 560/250 ns are measured with a cut‐off frequency of 530 kHz for the OPD incorporating a 250‐nm‐thick 1:1 blend. This OPD provides superior performance, with a high detectivity of 2.98 × 10 13 Jones and a wide linear dynamic range of 138 dB (at 530 nm (−1 V)). In addition, the ultralow dark current of the OPD retains excellent long‐term stability over 500 h of aging testing (thermal stress, ambient conditions, and continuous illumination). With the integration of specific light filters, a system is realized for the efficient detection of indoor plant‐growth lighting, allowing the rapid and accurate detection (>97%) of photosynthetic photon flux at various wavelengths of light that directly determine the photosynthesis and photomorphogenesis of indoor plants, supervised by machine learning. The artificial intelligence‐trained OPD effectively improves detection accuracy.