Benlin He

•CQDs are converted from soybean powders by a hydrothermal method.•The biomass converted CQDs are used for all-weather DSSCs.•The so-called all-weather DSSCs can generate electricity in the daytime and dark.•A dark efficiency as high as 7.97% is determined on the all-weather photovoltaics.•The launched solar cell extend our knowledge of advanced all-weather solar cells.A great challenge for state-of-the-art photovoltaic devices is to realize electric power generation in all weathers. We constructively demonstrate here the conversion from biomass to carbon quantum dots for all-weather carbon quantum dot solar cells that can generate electricity in the daytime and in the dark. The combination of green-emitting long persistence phosphors with mesoscopic titanium dioxide realizes optical storage by composite photoanode under illumination and excitation to monochromatic green light in the dark. The optimized all-weather solar cell yields maximized dark power conversion efficiency as high as 7.97% along with persistent electricity output for several hours. This work begins a photovoltaic revolution to forward all-weather solar cells as future energy solutions.Download high-res image (115KB)Download full-size image

Transparent molybdenum sulfide decorated polyaniline complex counter electrodes for efficient bifacial dye-sensitized solar cells

Co-reporter:Benlin He, Xin Zhang, Hongna Zhang, Jinyu Li, ... Qunwei Tang

Solar Energy 2017 Volume 147(Volume 147) pp:

Publication Date(Web):1 May 2017

DOI:10.1016/j.solener.2017.03.059

•Aniline-MoS2 complexes are synthesized by a reflux method.•PANi-MoS2 complexes are employed as cost-effective and transparent CEs.•The incident light from rear side can compensate for the light from anode.•The DSSC employing PANi-6 wt‰ MoS2 complex CE shows a bifacial efficiency of 9.71%Exploration of cost-effective and transparent counter electrodes (CEs) with high electrocatalytic activity has been a persistent objective of bifacial dye-sensitized solar cells (DSSCs) development. Here, with an aim of accelerating charge transfer and increasing the active sites of a transparent CE, molybdenum sulfide (MoS2) decorated aniline complexes are synthesized by a reflux technique and subsequently in-situ polymerized for transparent polyaniline (PANi)-MoS2 complex CEs for efficient bifacial DSSCs. The preliminary results indicate that the electrocatalytic activity toward I3− reduction of PANi-MoS2 complex CE is dramatically enhanced due to the fast charge transfer between PANi (N atoms) and MoS2 (Mo atoms) by the metal (dπ)-nitrogen (pπ) antibonding interaction. Owing to the high optical transparency, electrocatalytic reduction toward I3− species, superior charge-transfer ability for I−/I3− redox couples, the bifacial DSSCs based on PANi-6 wt‰ MoS2 complexes CE yield a maximum power conversion efficiency of 7.99% from front irradiation, 3.40% from rear irradiation and 9.71% from both irradiation, which are higher than front, rear and both efficiencies of 6.37%, 1.78% and 7.50% for DSSC employing PANi CE, respectively. The high optical transparency and electrocatalytic activity along with simple preparation, relatively low cost and scalability demonstrate the potential use of PANi-MoS2 complex as a robust CE in bifacial DSSCs.

Enhanced light harvesting of TiO2/La0.95Tb0.05PO4 photoanodes for dye-sensitized solar cells

Co-reporter:Hongna Zhang, Benlin He, Qunwei Tang

Materials Chemistry and Physics 2016 Volume 173() pp:340-346

Publication Date(Web):15 April 2016

DOI:10.1016/j.matchemphys.2016.02.021

•TiO2/La0.95Tb0.05PO4 nanocrystallites are fabricated by a facile hydrothermal method.•The light intensity and therefore dye excitation have been markedly enhanced.•A conversion efficiency of 7.27% for the DSSC employing TiO2/0.5 wt% La0.95Tb0.05PO4 is obtained.•The strategy provides new opportunities for efficient DSSCs.With an aim of enhancing light harvesting for dye adsorption and therefore photovoltaic performances of dye-sensitized solar cells (DSSCs), we present here an employment of La0.95Tb0.05PO4 incorporated TiO2 nanocrystallites as photoanodes. The preliminary results demonstrate that the dye absorption and therefore electron generation have been markedly enhanced, arising from the conversion of ultraviolet to visible light by La0.95Tb0.05PO4. The crystal structure and light harvesting performances of photoanodes are optimized by adjusting La0.95Tb0.05PO4 dosage. The power conversion efficiency is enhanced from 6.52% for pristine TiO2 based DSSC to 7.27% for the device employing TiO2/0.5 wt% La0.95Tb0.05PO4, yielding an efficiency enhancement by 11.35%. This study provides a new strategy for the fabrication of highly efficient DSSCs.

Solid-state dye-sensitized solar cells from poly(ethylene oxide)/polyaniline electrolytes with catalytic and hole-transporting characteristics

Co-reporter:Yanyan Duan, Qunwei Tang, Yuran Chen, Zhiyuan Zhao, Yang Lv, Mengjin Hou, Peizhi Yang, Benlin He and Liangmin Yu

Journal of Materials Chemistry A 2015 vol. 3(Issue 10) pp:5368-5374

Publication Date(Web):22 Jan 2015

DOI:10.1039/C4TA06393G

The pursuit of cost-effective and efficient solid-state electrolytes is a persistent objective for dye-sensitized solar cells (DSSCs). Herein, we present the experimental design of iodide/triiodide (I−/I3−)-incorporated poly(ethylene oxide)/polyaniline (PEO/PANi) solid-state electrolytes, aiming at expanding the catalytic event of I3− reduction from the electrolyte/counter electrode interface to both the interface and electrolyte system and shortening the charge diffusion path length. Except for I− species, the conjugated PANi is also responsible for dye regeneration and hole transfer to the counter electrode. A DSSC with (I−/I3−)-incorporated PEO/1.0 wt% PANi electrolyte yields a maximum efficiency of 6.1% in comparison with 0.8% obtained from a PANi-free electrolyte-based solar cell and 0.1% for a PANi-based solar cell.

A dye-sensitized solar cell having polyaniline species in each component with 3.1%-efficiency

Co-reporter:Yanyan Duan, Yuran Chen, Qunwei Tang, Zhiyuan Zhao, Mengjin Hou, Ru Li, Benlin He, Liangmin Yu, Peizhi Yang, Zhiming Zhang

Journal of Power Sources 2015 Volume 284() pp:178-185

Publication Date(Web):15 June 2015

DOI:10.1016/j.jpowsour.2015.03.032

•The DSSC having PANi species in each component yield an efficiency of 3.1%.•The solar cell consists of a PANi/TiO2 anode, a PANi CE, and a PANi electrolyte.•The PANi electrolyte can shorten charge diffusion path length.•The new concept is also applicable to all-carbon solar cells, etc.Pursuit of technological implementation with no sacrifice of photovoltaic performances has been a persistent objective for dye-sensitized solar cells (DSSCs). We launch here the experimental realization of a class of DSSCs consisting of polyaniline (PANi) incorporated TiO2 anodes, PANi counter electrodes (CEs), and iodide doped PANi solid-state electrolytes. The PANi filled in photoanode can inject electrons for dye recovery, whereas the PANi CE fulfills the function of reducing triiodide into iodide ions. In particular, the solid PANi electrolyte has an ability of catalyzing triiodide species, shortening charge diffusion path length, and recovering dye molecules at anode/electrolyte interface. The photovoltaic performances are optimized by adjusting assembly process and lithium iodide dosage, yielding a maximum efficiency as high as 3.1% in the resultant DSSC device accompanied with fast start-up, multiple start/stop cycling, and good stability under persistent irradiation.

Multifunctional graphene incorporated polyacrylamide conducting gel electrolytes for efficient quasi-solid-state quantum dot-sensitized solar cells

Co-reporter:Jialong Duan, Qunwei Tang, Ru Li, Benlin He, Liangmin Yu, Peizhi Yang

Journal of Power Sources 2015 Volume 284() pp:369-376

Publication Date(Web):15 June 2015

DOI:10.1016/j.jpowsour.2015.03.060

•Graphene is incorporated into microporous PAAm matrix.•The catalytic reaction of redox couples is conducted into conducting gel electrolyte.•Liquid electrolyte is driven by osmotic pressure and capillary diffusion.•A power conversion efficiency of 2.34% is recorded in the quasi-solid-state QDSC.Pursuit of a high efficiency and stability has been a persistent objective for quantum dot-sensitized solar cells (QDSCs). Here we launch a strategy of synthesizing graphene implanted polyacrylamide (PAAm-G) conducting gel electrolytes for quasi-solid-state QDSCs. With an aim of elevating the dosage of S2−/Sx2− redox couples and therefore charge-transfer ability, both osmotic press across the PAAm-G and capillary force within the three-dimensional micropores are utilized as driving forces. A promising power conversion efficiency of 2.34% is recorded for the QDSCs by optimizing graphene dosage in the conducting gel electrolyte. The enhanced conversion efficiency of solar cell is attributed to the expanded catalytic area from counter electrolyte/electrolyte interface to both interface and the conducting gel electrolyte.

Cost-effective, transparent iron selenide nanoporous alloy counter electrode for bifacial dye-sensitized solar cell

Co-reporter:Juan Liu, Qunwei Tang, Benlin He, Liangmin Yu

Journal of Power Sources 2015 Volume 282() pp:79-86

Publication Date(Web):15 May 2015

DOI:10.1016/j.jpowsour.2015.02.045

•Nanoporous FeSe alloy counter electrodes are synthesized by a mild solution method.•Surfactant DBSA is utilized as a template for preparing nanopores.•The resultant FeSe alloy electrode has high optical transparency.•The transparent FeSe alloy CEs are used for bifacial DSSC applications.•The DSSC with FeSe CE yields front and rear efficiencies of 9.16% and 5.38%, respectively.Pursuit of cost-effective and efficient counter electrodes (CEs) is a persistent objective for dye-sensitized solar cells (DSSCs). We present here the design of transparent Fe–Se nanoporous alloy CEs for bifacial DSSC applications. Due to the superior charge-transfer ability for I−/I3− redox couples, electrocatalytic reduction toward I3− species, and optical transparency in visible-light region, the bifacial DSSC with FeSe alloy electrode yields maximum front and rear efficiencies of 9.16% and 5.38%, respectively. A fast start-up, high multiple start capability, and good stability of the FeSe alloy CE demonstrate the potential applications in driving solar panels. The impressive efficiency along with simple preparation of the cost-effective Fe–Se nanoporous alloy CEs highlights their potential application in robust bifacial DSSCs.

Graphene-incorporated quasi-solid-state dye-sensitized solar cells

Co-reporter:Xiaoxu Chen, Qunwei Tang, Benlin He and Haiyan Chen

RSC Advances 2015 vol. 5(Issue 54) pp:43402-43407

Publication Date(Web):28 Apr 2015

DOI:10.1039/C5RA05078B

The pursuit of technological implementation with no sacrifice of photovoltaic performances is a persistent objective for dye-sensitized solar cells (DSSCs). Herein, we report an experimental realization of a graphene-incorporated quasi-solid-state DSSC comprising a graphene/TiO2 anode, a graphene integrated polyacrylate–poly(ethylene glycol) (PAA–PEG) gel electrolyte with I−/I3− redox couples, and a graphene counter electrode. An efficiency of 3.62% is measured under global air mass irradiation for the quasi-solid-state solar cell with a graphene/TiO2 photoanode, a PAA–PEG/graphene gel electrolyte, and a graphene counter electrode. The new concept, along with promising results, demonstrates the potential application of the new solar cells for cost-effective electricity generation.

Alloying of platinum and molybdenum for transparent counter electrodes. A strategy of enhancing power output for bifacial dye-sensitized solar cells

Co-reporter:Huihui Zhang, Qunwei Tang and Benlin He

RSC Advances 2015 vol. 5(Issue 64) pp:51600-51607

Publication Date(Web):27 May 2015

DOI:10.1039/C5RA04735H

Designing a cost-effective counter electrode (CE) with no sacrifice of photovoltaic performances and power output for a bifacial dye-sensitized solar cell (DSSC) is a persistent objective in photovoltaic power generation. We present here the fabrication of a novel transparent binary Pt-Mo alloy CE by an electrochemical strategy for bifacial DSSC application with an aim of bringing down the cost for solar-to-electric conversion. Electrochemical, and therefore photovoltaic performances, are optimized by adjusting stoichiometries of Pt-Mo alloys. Due to high charge-transfer ability, electrocatalytic activity, and optical transparency, maximum power conversion efficiencies of 6.75% and 2.89% are recorded under front and rear irradiation, respectively, which are comparable to 6.74% and 2.47% from a pristine Pt electrode-based solar cell. Due to the compensation effect of light from a transparent alloy CE to the incident light from the anode, the maximum power output of a solar cell has been markedly enhanced under simultaneous irradiation in comparison with either side. The enhanced efficiency along with enhanced power output, fast start-up, multiple start capability, simple preparation, and low Pt dosage highlights the potential application of these cost-effective transparent Pt-Mo alloy CEs in bifacial DSSCs.

All-solid-state quantum dot-sensitized solar cell from plastic crystal electrolyte

Co-reporter:Jialong Duan, Qunwei Tang, Benlin He and Haiyan Chen

RSC Advances 2015 vol. 5(Issue 42) pp:33463-33467

Publication Date(Web):09 Apr 2015

DOI:10.1039/C5RA05275K

A plastic crystal based solid-state electrolyte composing of plastic crystal succinonitrile and sodium sulfide (Na2S) is creatively synthesized by a simple blending approach. The ionic conductivity, charge-transfer ability, and photovoltaic performance are optimized by adjusting the succinonitrile/Na2S ratio. An optimal power conversion efficiency of 1.29% is measured for its quantum dot-sensitized solar cell (QDSSC) under one sun irradiation. The impressive efficiency along with the simple preparation of the cost-effective Na2S integrated succinonitrile electrolytes highlights the potential application of plastic crystal electrolytes in solid-state QDSSCs.

Quasi-solid-state dye-sensitized solar cells from hydrophobic poly(hydroxyethyl methacrylate/glycerin)/polyaniline gel electrolyte

Co-reporter:Qinghua Li, Qunwei Tang, Haiyan Chen, Haitao Xu, Yuancheng Qin, Benlin He, Zhichao Liu, Suyue Jin, Lei Chu

Materials Chemistry and Physics 2014 Volume 144(Issue 3) pp:287-292

Publication Date(Web):15 April 2014

DOI:10.1016/j.matchemphys.2013.12.032

•Poly(HEMA/GR) was employed to combine with PANi in the 3D framework.•The conductivity and electrochemical performances were enhanced.•The conversion efficiency of the quasi-solid-state DSSC was 6.63%.Hydrophobic poly(hydroxyethyl methacrylate/glycerin) [poly(HEMA/GR)] gel with a three-dimensional (3D) framework was successfully fabricated and employed to integrate with polyaniline (PANi). The resultant poly(HEMA/GR)/PANi gel electrolyte exhibited interconnective porous structure for holding I−/I3−, giving a similar conduction mechanism and ionic conductivity to that of liquid system but a much enhanced retention of I−/I3− redox couple. Fourier transform infrared spectroscopy, X-ray diffraction patterns, cyclic voltammograms as well as electrochemical impedance spectroscopy were employed to evaluate the molecular structure, crystallinity, and the electrochemical behaviors, showing that the combination of PANi with poly(HEMA/GR) caused a lower charge-transfer resistance and higher electrocatalytic activity for the I3−/I− redox reaction in the gel electrolyte. An efficiency of 6.63% was recorded from the quasi-solid-state DSSC assembled with the poly(HEMA/GR)/PANi gel electrolyte at 100 mW cm−2.A poly(HEMA/GR)/PANi gel electrolyte is synthesized through in situ polymerization of PANi in 3D framework of poly(HEMA/GR) hydrophobic hydrogel. The recorded ionic conductivity and electrochemical performances are significantly enhanced by integrating with PANi The resultant overall photo-to-electric conversion efficiency is 6.63%. The high ionic conductivity, along with good electrolyte retention ability, reasonable DSSC performance, low cost, simple and scalable synthesis procedure, and competitive cost, promises the electrolyte to find applications in quasi-solid-state DSSCs.

Microporous gel electrolyte for quasi-solid-state dye-sensitized solar cell

Co-reporter:Yuancheng Qin;Xiaoxu Chen;Qunwei Tang;Qinghua Li;Kexin Chen;Suyue Jin;Weili Dai;Mingjun Li;Yu Xie;Yunhua Gao

Polymer Engineering & Science 2014 Volume 54( Issue 11) pp:2531-2535

Publication Date(Web):

DOI:10.1002/pen.23808

The extension of electrocatalytic reaction of I⁻/I₃⁻ from counter electrode/gel electrolyte interface to gel electrolyte can significantly enhance the redox kinetics and therefore conversion efficiency of dye-sensitized solar cells. Microporous gel electrolyte from polypyrrole integrated poly(hydroxyethyl methacrylate/cetytrimethylammonium bromide) [PPy-integrated poly (HEMA/CTAB)] is successfully synthesized by in-situ polymerization of pyrrole monomers in three-dimensional framework of porous poly(HEMA/CTAB) matrix. An ionic conductivity of 12.72 mS cm⁻¹ and activation energy of 8.65 kJ mol⁻¹ are obtained from PPy-integrated poly(HEMA/CTAB) gel electrolyte. Tafel polarization and electrochemical impedance spectroscopy are employed to characterize the electrocatalytic behaviors of the gel electrolytes. The resultant quasi-solid-state dye-sensitized solar cell shows a light-to-electrical conversion efficiency of 6.68%. POLYM. ENG. SCI., 54:2531–2535, 2014. © 2013 Society of Plastics Engineers

Imbibition of polypyrrole into three-dimensional poly(hydroxyethyl methacrylate/glycerol) gel electrolyte for robust quasi-solid-state dye-sensitized solar cells

Co-reporter:Qinghua Li, Xiaoxu Chen, Qunwei Tang, Haitao Xu, Benlin He and Yuancheng Qin

Journal of Materials Chemistry A 2013 vol. 1(Issue 27) pp:8055-8060

Publication Date(Web):03 May 2013

DOI:10.1039/C3TA11166K

Hydrophobic poly(hydroxyethyl methacrylate/glycerol) [poly(HEMA/GR)] gel with a three-dimensional (3D) framework was successfully fabricated and employed to integrate with polypyrrole (PPy). The resultant PPy imbibed poly(HEMA/GR) gel electrolyte exhibited interconnective porous structure for holding I−/I3−, giving a similar conduction mechanism and ionic conductivity to that of a liquid system but a much enhanced retention of I−/I3− redox couple. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction technique, Tafel-polarization measurements as well as electrochemical impedance spectroscopy were employed to evaluate the morphology, molecular structure, crystallinity, and the electrochemical behaviors. The results showed that the combination of PPy with poly(HEMA/GR) caused a lower charge-transfer resistance and higher electrocatalytic activity for the I−/I3− redox reaction in the gel electrolyte. The resultant quasi-solid-state dye-sensitized solar cells based on PPy imbibed poly(HEMA/GR) gel electrolyte gave an overall light-to-electric conversion efficiency of 6.63%.

Preparation and electrochemical properties of polyaniline/-RuCl3.xH2O composites for supercapacitor

Co-reporter:Benlin He;Xin Meng;Yongbo Zhu ;Qunwei Tang

Polymer Composites 2013 Volume 34( Issue 12) pp:2142-2147

Publication Date(Web):

DOI:10.1002/pc.22623

Polyaniline/α-RuCl₃.xH₂O composites were successfully synthesized by an in-situ chemical polymerization and employed as new electrode materials in supercapacitors. The synthesized composites were characterized physically by scanning electronic microscope (SEM). The electrochemical capacitance performance of these composites was investigated by cyclic voltammetry, galvanostatic charge–discharge tests and AC impedance spectroscopy with a three-electrode system in 1 mol l⁻¹ NaNO₃ aqueous solution electrolyte. The polyaniline/α-RuCl₃.xH₂O composites electrodes showed much higher specific capacitance, better power characteristics and were more promising for application in capacitor than pure polyaniline electrode. The effect and role of α-RuCl₃.xH₂O in the composite electrode were also discussed in detail. POLYM. COMPOS., 34:2142–2147, 2013. © 2013 Society of Plastics Engineers