Daocheng Pan

Synthesis of Cu−In−S Ternary Nanocrystals with Tunable Structure and Composition

Nearly monodisperse Cu-In-S ternary nanocrystals with tunable composition, crystalline structure, and size were synthesized by a hot-injection method using mixed generic precursors. Such ternary nanocrystals with zincblende and wurtzite structure were reported for the first time. This work correlates the crystalline structure of the binary ZnS nanoparticles with those of ternary Cu-In-S nanocrystals, demonstrating the feasibility of making their alloyed or core/shell structure. Furthermore, this work may provide suitable material candidates for low-cost, high-efficiency solar cell fabrication.

Fabrication of a Cu2ZnSn(S,Se)4 Photovoltaic Device by a Low-Toxicity Ethanol Solution Process

Homogeneous molecular precursor solutions are excellent choices for obtaining smooth absorber layers, and they offer the potential to significantly lower the manufacturing cost of solar cells. Here, we present a thermally degradable metal butyldithiocarbamate-based solution approach to fabricate Cu2ZnSn(S,Se)4 solar cells. Low-cost Cu2O, ZnO, and SnO were used as the starting materials and were dissolved in the ethanol solution of butyldithiocarbamic acid. By tuning the composition of the Cu2ZnSn(S,Se)4 thin film, a power conversion efficiency of 6.03% on the basis of the active area has been achieved.

A general strategy for synthesis of quaternary semiconductor Cu2MSnS4 (M = Co2+, Fe2+, Ni2+, Mn2+) nanocrystals

Quaternary semiconductor Cu2MSnS4 (M = Co2+, Fe2+, Ni2+, Mn2+) nanocrystals have been successfully synthesized via a simple and mild solvothermal method. Cu2FeSnS4 and Cu2CoSnS4 show a spherical shape; Cu2NiSnS4 and Cu2MnSnS4 possess a nail-like structure and a rod-like structure. The four types of nanocrystals exhibit significantly different magnetic properties. Cu2FeSnS4 and Cu2CoSnS4 nanoparticles show ferromagnetic behavior; Cu2MnSnS4 and Cu2NiSnS4 nanorods exhibit superparamagnetic behavior at low temperature. The band gaps of Cu2MSnS4 (M = Co, Fe, Ni, Mn) nanocrystals are in the range of 1.2–1.5 eV, indicating a high potential application in low-cost thin film solar cells.

Large-Scale Synthesis of Well-Dispersed Copper Nanowires in an Electric Pressure Cooker and Their Application in Transparent and Conductive Networks

We present a novel large-scale synthetic method for well-separated copper nanowires (CuNWs) in a commercial electric pressure cooker under mild reaction conditions. CuNWs (∼2.1 g) can be prepared in a batch with the cost of

Green and facile synthesis of water-soluble Cu-In-S/ZnS Core/Shell quantum dots

4.20/g. Well-dispersed polyvinylpyrrolidone-capped CuNWs were obtained via a ligand-exchange method. The transparent and conductive CuNW networks with excellent electrical conductivity and high optical transmittance (30 Ω/□ at 86% transmittance, respectively) were fabricated by a spin-coating process.

Synthesis and photoresponse of novel Cu2CdSnS4 semiconductor nanorods

Water-soluble Cu-In-S/ZnS core/shell quantum dots with a photoluminescence quantum yield up to 38% and an emission peak tunable from 543 to 625 nm have been successfully synthesized. All of the synthetic procedures were conducted in an aqueous solution at 95 °C under open-air conditions. L-Glutathione and sodium citrate were used as the dual stabilizing agents to balance the reactivity between copper and indium ions.

Solution-Processed Highly Efficient Cu2ZnSnSe4 Thin Film Solar Cells by Dissolution of Elemental Cu, Zn, Sn, and Se Powders

Novel semiconductor Cu2CdSnS4 nanorods with a wurtzite structure have been successfully synthesized and characterized in detail. The suitable band gap of 1.4 eV and photoresponse property of Cu2CdSnS4 nanorods indicate that they have a high potential application in low-cost thin film solar cells.

Quantum-Dot-Decorated Robust Transductable Bioluminescent Nanocapsules

Solution deposition approaches play an important role in reducing the manufacturing cost of Cu2ZnSnSe4 (CZTSe) thin film solar cells. Here, we present a novel precursor-based solution approach to fabricate highly efficient CZTSe solar cells. In this approach, low-cost elemental Cu, Zn, Sn, and Se powders were simultaneously dissolved in the solution of thioglycolic acid and ethanolamine, forming a homogeneous CZTSe precursor solution to deposit CZTSe nanocrystal thin films. Based on high-quality CZTSe absorber layer, pure selenide CZTSe solar cell with a photoelectric conversion efficiency of 8.02% has been achieved without antireflection coating.

Metal sulfide precursor aqueous solutions for fabrication of Cu2ZnSn(S,Se)4 thin film solar cells

Bioluminescence, due to its high sensitivity, has been exploited in various analytical and imaging applications. In this work, we report a highly stable, cell-transductable, and wavelength-tunable bioluminescence system achieved with an elegant and simple design. Using aqueous in situ polymerization on a bioluminescent enzyme anchored with polymerizable vinyl groups, we obtained nanosized core-shell nanocapsules with the enzyme as the core and a cross-linked thin polymer net as the shell. These nanocapsules possess greatly enhanced stability, retained bioactivity, and a readily engineered surface. In particular, by incorporating polymerizable amines in the polymerization, we endowed the nanocapsules with efficient cell-transduction and sufficient conjugation sites for follow-up modification. Following in situ polymerization, decorating the polymer shell with fluorescent quantum dots allowed us to access a continuous tunable wavelength, which extends the application of such bioluminescent nanocapsules, especially in deep tissue. In addition, the unique core-shell structure and adequate conjugation sites on surface enabled us to maximize the BRET efficiency by adjusting the QD/enzyme conjugation ratio.

Alloyed (ZnSe)x(CuInSe2)1–x and CuInSexS2–x Nanocrystals with a Monophase Zinc Blende Structure over the Entire Composition Range

Aqueous solution deposition of metal chalcogenide semiconductor thin films is considered a green and low-cost approach. However, it is hard to find a general aqueous solution approach to deposit various kinds of high-quality metal sulfide thin films. Here, we describe a green and robust ammonium thioglycolate aqueous solution approach, and fifteen types of metal sulfide precursor solutions (metal = Cu, Zn, Sn, Ge, In, Sb, Mg, Cd, Mn, Bi, Fe, Ni, Li, Na, K) can be prepared using metal oxides or metal hydroxides as raw materials at room temperature under an air atmosphere. Moreover, elemental sulfur and selenium can also be highly dissolved. By this green route, high quality CZTS nanocrystal thin films can be deposited by directly coating the mixed Cu, Zn, and Sn precursor solutions without the need for complex nanocrystal synthesis. The remarkable power conversion efficiency of 6.62% was achieved, which is the highest value for aqueous solution deposited CZTSSe thin film solar cells.