Tunable emission carbonized polymer dots (CPDs) are highly desirable for the preparation of optoelectronic devices, especially white light-emitting diodes (WLEDs). In most available studies, polychromatic CPDs are synthesized using aromatic molecules as precursors. However, few studies report the successful synthesis of polychromatic CPDs using two or more unconjugated precursors. In this work, we prepare multicolor fluorescent CPDs from a single unconjugated precursor, glucose, via a hydrothermal reaction. By controlling the particle size and degree of graphitization of the synthesized CPDs, their emission wavelength can be tuned in the range 440–625 nm (i.e., almost the entire visible region). Furthermore, the CPDs can be used to construct LEDs of varying colors, including WLEDs (CIE coordinates: 0.34, 0.36) with the correlated color temperature and color rendering index of 4997 K and 92.69, respectively. In brief, the strategy proposed in this study successfully converts unconjugated glucose into high-performance LEDs with great application potential.

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We present electrical and optical characteristics of single-ion transport light-emitting electrochemical cells ͑SLECs͒ based on a blend film of poly͑p-phenylene vinylene͒ derivative with ion-conducting side groups and ionized polyurethane-poly͑ethylene glycol͒. The turn-on voltage of the SLECs is lower than 4 V. The response time of the SLECs is less than 10 ms, which is approximately two orders of magnitude faster than that of conventional bi-ionic transport light-emitting electrochemical cells. The quick response can be explained on the basis of both good compatibility between the two polymers and weak scattering behavior of the counter ions. In addition, according to the transient current and electroluminescence characteristics, we reveal that the electrical field is close to zero in the inner of the SLEC under the condition of steady state.

Polymeric semiconductors are crucial candidates for the construction of next‐generation flexible and printable electronic devices. By virtue of the successful preparation of monodispersed colloidal solution in orthogonal solvent, poly(3‐hexylthiophene) (P3HT) nanofibers are developed into versatile building blocks for nanoelectronics and their compatibilities are verified with photolithographic lift‐off technology. Then, the joint efforts from both the bottom‐up hierarchical self‐assembly and top‐down self‐alignment technology have led to the realization of lateral asymmetric heterojunctions with resolution better than 1 µm. As a result, planar photovoltaic devices incorporating N,Nʹ‐dioctyl‐3,4,9,10‐perylenedicarboximide and P3HT supramolecular nanowires as active components are constructed with the cathode‐to‐anode distance being tuned from ≈0.1 to 1–2 µm. Based on such a novel device configuration, an interesting phenomenon of channel‐length‐dependent photovoltaic efficiency is observed for the first time, strongly suggesting the impact of near‐field light intensity on the performance of nanophotonic devices.

ABSTRACT:We present the electrical and optical characteristics of a single-ion transport light-emitting electrochemical cell (SLEC) based on poly(p-phenylene vinylene) (PPV) derivative containing aryl-substituted oxadiazole in the backbone (MEH-OPPV). Ionized polyurethane-poly(ethylene glycol) (PUI) used as polymer electrolyte is introduced into the active layer of the SLEC. The turn-on voltage of the SLEC is about 3 V according to its current density-voltage (J-V) characteristics. The response time of the SLEC is less than 10 ms, lower than that of normal LECs by two orders of magnitudes roughly. The reasons of the quick response for the SLEC are discussed in the article.