The temperature dependent PL measurement is performed using an excitation wavelength 544 nm, excitation power: 150 μW, integral time 1 sec for untreated and H-TFSI-only treated samples. Excitation wavelength 561 nm, excitation power 150 μW, and integral time 1 sec are used for the treated sample. The microscope steady-state PL measurement was carried out using a WITec alpha 300 s setup and has been described previously. Importantly, a 405 nm continuous wave laser (Coherent CUBE) was used as the excitation source. A long pass filter with a cutoff wavelength of 450 mm was fitted before signal collection to block excitation scatter. The light was coupled with an optical fiber to the microscope and focused using a 20×