Guanidine isothiocyanate new skill "release": auxiliary surface matrix Engineering Technology

Guanidine isothiocyanate is widely used in the field of solar cells. It can improve the stability and photoelectric conversion efficiency of new concept cells such as perovskite solar cells. Recently, scientists have "cracked" the new skills of guanidine isothiocyanate and found its new function in the field of solar cells, that is, auxiliary surface matrix engineering technology for high-efficiency perovskite quantum dot photovoltaic materials.

Ma Wanli's team underwent mild thermal annealing through the ligand exchange process triggered by guanidine isothiocyanate (called "le-ta"), A ligand assisted surface matrix strategy is provided for the engineering design of the surface and stacking state of metal halide perovskite quantum dots (PE QDs). The relevant results are published in the recent journal new functional materials.

The researchers found that the surface matrix formed by guanidine isothiocyanate on cspbi3 QDs was mainly composed of cationic guanidine (GA +) rather than SCN -, which maintained a complete cubic structure and promoted the electrical interaction between QD solids. In addition, through experiments, cspbi3 QDs of GA matrix show significantly enhanced charge mobility and carrier diffusion length, so that the highest power conversion efficiency of 15.21% can be achieved when assembled in photovoltaic, which is one of the highest power conversion efficiency among all metal halide perovskite quantum dots. Moreover, the ligand exchange process triggered by guanidine isothiocyanate has a similar effect when applied to other PE QD photovoltaic systems (such as cspbbr3 and fapbi3), which proves that the "le-ta" method can adjust the versatility of a variety of PE QD surfaces.

The release of guanidine isothiocyanate's new skills in the field of new energy batteries may provide new guidelines for the construction of conductive and structurally complete PE QD solids for efficient optoelectronic devices.