Yongfeng Luo

Photovoltaic Wire Derived from a Graphene Composite Fiber Achieving an 8.45 % Energy Conversion Efficiency†

Wired for light: Novel wire-shaped photovoltaic devices have been developed from graphene/Pt composite fibers. The high flexibility, mechanical strength, and electrical conductivity of graphene composite fibers resulted in a maximum energy conversion efficiency of 8.45 %, which is much higher than that of other wire-shaped photovoltaic devices.

Self-Healable Electrically Conducting Wires for Wearable Microelectronics†

Electrically conducting wires play a critical role in the advancement of modern electronics and in particular are an important key to the development of next-generation wearable microelectronics. However, the thin conducting wires can easily break during use, and the whole device fails to function as a result. Herein, a new family of high-performance conducting wires that can self-heal after breaking has been developed by wrapping sheets of aligned carbon nanotubes around polymer fibers. The aligned carbon nanotubes offer an effective strategy for the self-healing of the electric conductivity, whereas the polymer fiber recovers its mechanical strength. A self-healable wire-shaped supercapacitor fabricated from a wire electrode of this type maintained a high capacitance after breaking and self-healing.

An integrated device for both photoelectric conversion and energy storage based on free-standing and aligned carbon nanotube film

An all-solid-state and integrated device in which photoelectric conversion and energy storage are simultaneously realized has been developed from free-standing and aligned carbon nanotube films or carbon nanotube–polyaniline composite films. Due to the aligned structure and excellent electronic property of the film electrode, the integrated device exhibits a high entire photoelectric conversion and storage efficiency of ∼5.12%. The novel devices can also be flexible, and show promising applications in a wide variety of fields, particularly for portable electronic equipment.

Core-sheath carbon nanostructured fibers for efficient wire-shaped dye-sensitized solar cells.

A novel core-sheath carbon nanostructured fiber is created with high tensile strength, electrical conductivity, and electrocatalytic activity. In particular, the designed ribbon-like nanostructure on the outer surface favors the attachment and impregnation of a second functional phase that is critical for electronic devices. As a demonstration, novel wire-shaped dye-sensitized solar cells are produced with high energy conversion efficiencies up to 6.83%.

Aligned carbon nanotube/molybdenum disulfide hybrids for effective fibrous supercapacitors and lithium ion batteries

An aligned carbon nanotube/MoS2 nanosheet hybrid fiber was synthesized to display combined remarkable mechanical, electronic and electrochemical properties. It was used to fabricate flexible fibrous supercapacitors and lithium ion batteries with a high specific capacitance of 135 F cm−3 and a high specific capacity of 1298 mA h g−1, respectively.

A novel fabrication of a well distributed and aligned carbon nanotube film electrode for dye-sensitized solar cells†

Carbon nanotubes (CNTs) have been recently fabricated into macroscopic films to improve their practical applications in a wide variety of fields, e.g. electrode materials. In the current CNT electrodes however, CNTs are typically interconnected to form networks or are aligned as lots of bundles, and the resulting photovoltaic devices based on the CNT electrodes have typically shown low energy conversion efficiencies. Here we report a new and general drying approach to make a well distributed and aligned CNT film which exhibits a rapid charge separation and transport. As a demonstration, it has been used as a counter electrode to fabricate dye-sensitized solar cells with an energy conversion efficiency of 9.05%.

Flexible electroluminescent fiber fabricated from coaxially wound carbon nanotube sheets

A fiber-shaped polymer light-emitting electrochemical cell (PLEC) was developed by sandwiching an electroluminescent polymer layer between two aligned carbon nanotube (CNT) sheet electrodes. Similar to a conventional planar PLEC, the electroluminescent polymer layer and two carbon nanotube electrodes are closely and stably contacted, so that the injected charges can be rapidly and efficiently transported. Due to their one-dimensional structure, the fiber-shaped PLEC demonstrates unique and promising advantages, e.g., the luminance is almost independent on the observation angle. In addition, the fiber-shaped PLEC is thin, lightweight and flexible, which bespeaks a promising future for various electronic textiles.

An intercalated graphene/(molybdenum disulfide) hybrid fiber for capacitive energy storage

It is critical but remains challenging to make fiber-shaped energy storage systems to satisfy the rapidly developing area of flexible and wearable electronics due to the difficulty in finding high-performance fiber electrodes. Herein, we designed a one-step hydrothermal strategy to synthesize graphene/(molybdenum disulfide) hybrid fiber electrodes with a novel intercalated nanostructure that effectively combined the high electrical conductivity from graphene sheets and high pseudocapacitance from molybdenum disulfide sheets. The intercalated nanostructure also simultaneously provided large ion-accessible surface areas and a high active material content of up to 33.98 wt%. The resulting fiber-shaped supercapacitor exhibited a high specific capacitance of 368 F cm−3.

The cellulose nanofibers for optoelectronic conversion and energy storage

Cellulose widely exists in plant tissues. Due to the large pores between the cellulose units, the regular paper is nontransparent that cannot be used in the optoelectronic devices. But some chemical and physical methods such as 2,2,6,6-tetramethylpiperidine-1- oxyl radical (TEMPO) oxidation can be used to improve the pores scale between the cellulose units to reach nanometer level. The cellulose nanofibers (CNFs) have good mechanical strength, flexibility, thermostability, and low thermal expansion. The paper made of these nanofibers represent a kind of novel nanostructured material with ultrahigh transparency, ultrahigh haze, conductivity, biodegradable, reproducible, low pollution, environment friendly and so on. These advantages make the novel nanostructured paper apply in the optoelectronic device possible, such as electronics energy storage devices. This kind of paper is considered most likely to replace traditional materials like plastics and glass, which is attracting widespread attention, and the related research has also been reported. The purpose of this paper is to review CNFs which are applied in optoelectronic conversion and energy storage.

Coupling of localized surface plasmon modes in compound structure with metallic nanoparticle and nanohole arrays

We have investigated the effect of the coupling of localized surface plasmon (LSP) on the transmission properties of a compound structure with metallic particle and hole arrays. It is found that the variation in longitudinal interval G between particle and hole arrays leads to the shift in transmission peak and the new transmission peak, which are due to the change in coupling strength of LSP modes and the formation of coaxial guide mode, respectively. The lateral displacement Lx (parallel to the polarization direction of incident light) results in the splitting of transmission peak, originating from the variation in coupling manner of LSP modes, while the lateral displacement Ly (perpendicular to the polarization direction of incident light) causes the reduction and redshift in transmission peak.