Organic parallel grouping crystals without grain boundary

Organic crystal-based micro/nanostructures with morphology-driven photons/electrons transport characteristics demonstrate exceptional potential for the development of optoelectronic functional materials. However, the construction of continuities and lossless interfaces within multicomponent structures remains a significant challenge, primarily due to inherent material differences and current technology limits. Herein, organic parallel grouping crystals (OPGCs), which devoid of grain boundaries between crystals via a solution viscosity-induced binuclear co-growth strategy, are designed to enhance photon transmission efficiency. Notably, the symbiotic phenomenon among components within OPGCs is precisely regulated by manipulating the solvent viscosity to exceed 0.5 mPa·s through adjustments in factors such as the cooling rate, solvent type, concentration. Compared with the low photon transmission efficiency (2.1%) caused by the discontinuous splicing interface, the elimination of grain boundaries significantly enhances the interlayer photon transmission efficiency of OPGCs, resulting in an overlap degree-dependent adjustable transmission efficiency ranging from 21.3% to 54.9%. This symbiotic strategy demonstrates universality to small molecules, coordination compounds, and cocrystals, enabling the construction of parallel grouping structures comprising single- or multi-component crystals.