| Affiliation: | 1. SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology, Shenzhen University, Shenzhen, 518060 P. R. China;2. Department of Physics, National University of Singapore, 117542 Singapore, Singapore Center for advanced 2D materials, National University of Singapore, 117546 Singapore, Singapore;3. Department of Chemistry, National University of Singapore, 117543 Singapore, Singapore;4. Center for Organic Photonics and Electronics and School of, Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, 30332 USA |
| Abstract: | In this work, a heterostructure obtained by vacuum evaporation of a strong molecular n-dopant, [RuCp*(mes)]2, onto black phosphorus (BP) is reported, along with the systematic investigation of the interfacial structure and properties by various in situ characterization techniques. Ultraviolet photoelectron spectra (UPS) showed a large decrease in the work function of BP and a new peak within the bandgap, which is attributed to electron transfer from dopants to the underlying BP. The electrons trapped at the interface act as hole traps and induce photogating effect so that a photodetector based on BP–organoruthenium complex heterostructure demonstrates a photoresponsivity of 5.5 mA W−1 and an EQE of 1.3 % at 515 nm, a tenfold improvement compared to the pristine BP device. |
