Carbon Nanolights in Piezopolymers are Self‐Organizing Toward Color Tunable Luminous Hybrids for Kinetic Energy Harvesting

Abstract

Herein, an all‐solid‐state sequential self‐organization and self‐assembly process is reported for the in situ construction of a color tunable luminous inorganic/polymer hybrid with high direct piezoresponse. The primary inorganic self‐organization in solid polymer and the subsequent polymer self‐assembly are achieved at high pressure with the first utilization of piezo‐copolymer (PVDF‐TrFE) as the host matrix of guest carbon quantum dots (CQDs). This process induces the spontaneous formation of a highly ordered, microscale, polygonal, and hierarchically structured CQDs/PVDF‐TrFE hybrid with multicolor photoluminescence, consisting of very thermodynamic stable polar crystalline nanowire arrays. The electrical polarization‐free CQDs/PVDF‐TrFE hybrids can efficiently harvest the environmental available kinetic mechanical energy with a new large‐scale group‐cooperation mechanism. The open‐circuit voltage and short‐circuit current outputs reach up to 29.6 V cm−2 and 550 nA cm−2, respectively. The CQDs/PVDF‐TrFE–based hybrid nanogenerator demonstrates drastically improved durable and reliable features during the real‐time demonstration of powering commercial light emitting diodes. No attenuation/fluctuation of the electrical signals is observed for ≈10 000 continuous working cycles. This study may offer a new design concept for progressively but spontaneously constructing novel multiple self‐adaptive complex inorganic/polymer hybrids that promise applications in the next generation of self‐powered autonomous optoelectronic devices.

Red carbon dot directed biocrystalline alignment for piezoelectric energy harvesting

“…Similar to diamonds, the individual R-CQDs have clear lattice stripes with a spacing of 0.23 nm, indicating higher crystallinity. 32–56 Also, TEM further confirms that R-CQDs were successfully introduced into the CQDs/PVA/CS nanofibers, fabricated by electrospinning a water based solution (Fig. 1b and c).…”

“…The redshifted PL emission, favorable to biomedicine, may be attributed to the interactions between R-CQD surfaces and PVA/CS molecules during hybridisation. 32–56 The room-temperature absolute PL QY of CQDs/PVA/CS is determined to be 8.97% for red emission (Fig. S2b, ESI†), which is sufficient to meet some attractive biomedical and optoelectronic applications.…”

“…S2b, ESI†), which is sufficient to meet some attractive biomedical and optoelectronic applications. 32–56…”

“…Red emissive carbon quantum dots (R-CQDs), the new kind of the carbon nanomaterial family, have attracted increasing attention in the fields of biomedicine and optoelectronic devices, due to numerous merits such as high photostability, low cytotoxicity, water dispersibility, excellent biocompatibility, and controllable biodegradability. 32–56 Under optimum long-wavelength excitation, scarce, true R-CQDs always show a dominant photoluminescence (PL) emission peak longer than 600 nm. 32–50 The emission wavelengths of R-CQDs avoid the blue autofluorescence and photodamage of the biological matrix, and provide deeper tissue penetration.…”

Microstructured PVDF Film with Improved Performance as Flexible Infrared Sensor

“…However, the rigidness of ferroelectric crystals and ceramics makes them unable to be applied in wearable flexible electronics. In comparison, ferroelectric polymers especially PVDF-based polymers, are optimal candidates for wearable flexible electronics because of their excellent flexibility, low energy consumption, low-cost process [ 24 , 25 , 26 , 27 , 28 , 29 ] and even self-powering ability [ 30 , 31 , 32 , 33 ]. The biggest disadvantage of PVDF-based polymer, however, is its low pyroelectric coefficient and, consequently, low output signal, making it difficult to use them in practical applications like their inorganic counterparts.…”