Temperature-dependent photoluminescence characterization and electrochemical applications of highly stable CsPb(Cl/Br)3-CNTs heterojunctions

CsPb(Cl/Br) 3 perovskite nanocrystals (NCs) materials were synthesized by a hot injection method. To enhance the stability of the perovskite , CsPb(Cl/Br) 3 - multiwalled carbon nanotubes (CNTs) composites were synthesized by the insitu growth method. First, the successful composite of CNTs and perovskite has been proved by X-ray photoelectron spectroscopy (XPS). After CsPb(Cl/Br) 3   NCs have grew on CNTs, the exciton lifetime decays from 8.2 ns to 4.5 ns, suggesting the presence of an additional electron transfer pathway between CNTs and CsPb(Cl/Br) 3  NCs. The photoluminescence (PL) properties of perovskite NCs and CsPb(Cl/Br) 3 -CNTs were evaluated using temperature-dependent PL spectroscopy . The exciton binding energy of the CsPb(Cl/Br) 3 -CNTs composites (59.28 meV) is higher than that of the CsPb(Cl/Br) 3  NCs (51.79 meV), indicating a more stable exciton state within the CsPb(Cl/Br) 3 -CNTs structure. The PL stability experimental results reveal a notable enhancement in the stability of CsPb(Cl/Br) 3 -CNTs composites compared to CsPb(Cl/Br) 3  NCs. In addition, electrochemical tests of CsPb(Cl/Br) 3 -CNTs show a low resistance to charge transfer ( R ct ) alongside a favorable photocurrent response. This work has proved that the novel CsPb(Cl/Br) 3 -CNTs composites not only exhibit outstanding moisture and UV resistance but also demonstrate remarkable potential optoelectronic device applications.