Synthesis of AgBiSe2 via a facile low temperature aqueous solution route for enhanced photoelectric properties devices

Accepted Manuscript Synthesis of AgBiSe2 via a facile low temperature aqueous solution route for enhanced photoelectric properties devices Xiao Fan, Jian Zhang, Yulin Yang, Debin Xia, Guohua Dong, Mengru Li, Lele Qiu, Yu Zhang, Ruiqing Fan PII:

S0022-4596(19)30370-6

DOI:

https://doi.org/10.1016/j.jssc.2019.07.036

Reference:

YJSSC 20875

To appear in:

Journal of Solid State Chemistry

Received Date: 7 May 2019 Revised Date:

19 July 2019

Accepted Date: 19 July 2019

Please cite this article as: X. Fan, J. Zhang, Y. Yang, D. Xia, G. Dong, M. Li, L. Qiu, Y. Zhang, R. Fan, Synthesis of AgBiSe2 via a facile low temperature aqueous solution route for enhanced photoelectric properties devices, Journal of Solid State Chemistry (2019), doi: https://doi.org/10.1016/ j.jssc.2019.07.036. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT

For Table of Contents Synthesis of AgBiSe2 via a Facile Low Temperature Aqueous Solution Route for

RI PT

Enhanced Photoelectric Properties Devices

EP

TE D

M AN U

SC

Xiao Fana, Jian Zhanga, Yulin Yang*a, Debin Xiaa, Guohua Dongb, Mengru Lia, Lele Qiua, Yu Zhangc, Ruiqing Fan*a

AC C

AgBiSe2 nanoparticles were successfully synthesized by a facile solution method under a low temperature (~373 K). The as-synthesized AgBiSe2 nanoparticles possess narrow size distribution (ca. 80 nm) and excellent light absorbance across the entire UV/Vis region. More important, AgBiSe2-based devices exhibit a reduced resistance of 0.53 Ω*m and markedly 50% improved absorption efficiency after annealing treatment. Importantly, these results may potentially be extended for the preparation of other ternary semiconductors.

ACCEPTED MANUSCRIPT Synthesis of AgBiSe2 via a Facile Low Temperature Aqueous Solution Route for Enhanced Photoelectric Properties Devices

RI PT

Xiao Fan, a Jian Zhang, a Yulin Yang, *a Debin Xia, a Guohua Dong, b Mengru Li, a Lele Qiu, a Yu Zhang c and Ruiqing Fan*a a

MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and

SC

Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.

College of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, P. R.

China. c

M AN U

b

Department of Telecommunication Engineering, Heilongjiang Communications polytechnic,

Qiqihar, 161002, P. R. China.

TE D

Corresponding Author: * Yulin Yang and Ruiqing Fan

AC C

EP

E-mail: [email protected]; E-mail: [email protected]

1

ACCEPTED MANUSCRIPT

Abstract: Silver dimetal chalcogenides ternary semiconductors are commonly obtained by complex and difficult synthetic process, such as high temperatures (~1100 K), long reaction times and

RI PT

mixture heterogeneity involving solid phases. Here, we present a facile aqueous synthesis route for the preparation of AgBiSe2 nanoparticles at low temperature (~373 K). The as-synthesized AgBiSe2 nanoparticles possess narrow size distribution (ca. 80 nm) and

SC

excellent light absorbance across the entire UV/Vis region. More important, AgBiSe2-based

M AN U

devices exhibit a reduced resistance of 0.53 Ω*m and markedly 50% improved absorption efficiency under monochromatic light after heating treatment. These results may potentially be extended for the preparation of other ternary semiconductors.

AC C

EP

TE D

KEYWORDS: AgBiSe2; Semiconductors; Synthesis route; photovoltaic devices; Solar energy materials

2

ACCEPTED MANUSCRIPT

1. Introduction While modern society has enjoyed rapid economic development, the increasing severity of energy and environmental problems has prompted increased global interest in the

RI PT

exploration and utilization of sustainable energy sources.[1, 2] In particular, nuclear and solar energy have been extensively studied as alternatives to fossil fuel derived technologies.[3-5] Semiconductor materials play an important role in the field of photoelectric conversion,[6-8] 9, 10]

The copper and silver based

SC

owing to their efficient conversion of solar energy.[2,

M AN U

I−V−VI2 (where I =Cu, Ag; V = Sb, Bi; and VI = S, Se, Te) semiconductors are promising photoelectric candidates for solar energy cells,[11-13] due to NIR band gaps,[14,

15]

large

absorption coefficients,[16] and excellent electronic properties, etc.[16-19] The electron transport capability of Bi2Se3 has been extensively studied and many successful results achieved,[20]

TE D

facilitating the application of topological insulators in optoelectronic field.[21] Besides, it has been reported that when Ag atoms doped into Bi2Se3 lattices, interstitial Agi and substitutional AgBi, two major types of lattice defects, modulate the thermal and electrical

EP

properties of Bi2Se3.[22, 23] When plenty of Ag atoms have been added to Bi2Se3 lattices, the

AC C

formation of AgBi was accompanied by the removal of holes, resulting in an increase in electron concentration and a decrease in carrier concentration. Therefore, as a member of I−V−VI2 semiconductors, AgBiSe2 possesses excellent photoelectric properties and potential research value in the field of optoelectronics. However, the majority of reports on syntheses of AgBiSe2 are based on a solid-state sintering method,[24,

25]

facing the problem of high-temperature (∼ 1000 K) and long

annealing time.[18, 23, 26, 27] G. Zeier’s group synthesized AgBiSe2 in a quartz vacuum tube at

3

ACCEPTED MANUSCRIPT 1123K for 10h, obtaining a purity of about 95%.[6] Furthermore, the products suffer from large particle size.[28] These drawbacks have limited the application of AgBiSe2 in the field of optoelectronics.[29-31] Recently,

Snee’s

group

have

synthesized

AgBiSe2

via

an

RI PT

organic-solution phase synthesis strategy.[11] However, this strategy was carried out in oleylamine solution system, which is also hostile to environment. In order to overcome the above-mentioned difficulties, we tried to develop an ideal synthetic strategy and avoid the

SC

harmful solution at the same time.

M AN U

Herein, we developed an effective way to synthesize AgBiSe2 via a solution phase synthesis strategy, avoiding high temperature and long annealing time. Na2SeSO3 precursor was prepared by the simple mixing of Se powder and Na2SO3 in boiling water under stirring. Subsequently, aqueous Bi(NO3)3 and AgNO3 suspensions were introduced followed by

TE D

stirring for 1.5 h to yield the target product. The obtained AgBiSe2 was then deposited under vacuum to form high quality thin films. Benefiting from the high crystallinity and uniform particle size, AgBiSe2 film exhibits strong light absorption intensity and wide light absorption

EP

range in optical measurements. Excellent electron transport properties of AgBiSe2 make it

AC C

useful in the field of optoelectronics. Moreover, our strategy may potentially be extended for the preparation of other ternary semiconductors.

2. Experimental Section 2.1 . Materials

Selenium power (Se, 99.5%, ACROS), nitrilotriacetic acid (C6H9NO6, 99%, Adamas), silver nitrate (AgNO3, AR, ≥99.8%) bismuth (III) nitrate pentahydrate (Bi(NO3)3·5H2O, 98%, Alfa Aesar), sodium sulfate anhydrous (Na2SO3, AR, ≥97%). All the chemicals were

4

ACCEPTED MANUSCRIPT purchased commercially without further purification.

2.2 . Synthesis of Na2SeSO3 solution 50 mL water and 2.4 g (20.0 mmol) Na2SO3 were added into a single-necked

RI PT

round-bottomed flask and slowly heated to 100 ℃ with stirring for 1 h. When the Na2SO3 completely dissolved, 0.79 g (10.0 mmol) Se power was added in the above solution. Then, the solution was heated at 100 ℃ for 1.5 h to obtain the precursor Na2SeSO3 solution.

SC

2.3 . Synthesis of AgBiSe2

M AN U

100 mL water and 0.61 g (1.25 mmol) Bi(NO3)3·5H2O, 2.4 g (32.00 mmol) of nitrilotriacetic acid, 0.17 g (1.00 mol) AgNO3 were added into a single-necked round-bottomed flask and heated at 70 ℃ for 30 minutes. The solution was kept stirring and the pH value was adjusted to 9.0 by ammonia solution, and the mixed solution turned into

TE D

milky white color slowly. Then, 15 mL as-prepared Na2SeSO3 solution was added in and the mixture was slowly heated and maintained at 90 ℃ for 1.5 h. Then the solution cooled down to room temperature, the black color AgBiSe2 nanocrystals generated at the bottom of the

AC C

and ethanol.

EP

flask. The as-synthesized composites were collected and washed several times with acetone

2.4 . Annealing Treatment of AgBiSe2 composites As-synthesized AgBiSe2 compounds was added into a quartz tube and slowly heated up to 350 ℃ and maintained for 3 h under N2 atmosphere. Afterward, the sample cooled down to room temperature and kept in N2 atmosphere.

2.5 . The preparation of AgBiSe2 film The fluorine-doped tin oxide (FTO) glasses were first cut into square bases of 1.5 cm *

5

ACCEPTED MANUSCRIPT 1.5 cm in size. Then FTO glasses were etched with Zn powder and hydrochloric acid (2 mol L-1). Next, the sheets were washed with detergent, deionized water, acetone, and isopropanol, followed by removing the last traces of organic residues through oxygen plasma treating for

RI PT

15 minutes. The as-synthesized powders were used as the source for evaporation and the vapor deposition was carried out in a vacuum evaporation apparatus. The current procedure of evaporation deposition was 0.5 Å/s. Finally, an AgBiSe2 film with a thickness of 400 nm

SC

was deposited by thermal evaporation.

M AN U

2.6 . Characterization

X-ray diffraction (XRD) measurements were performed by Shimadzu XRD-6000 instrument with Cu Kα radiation. Scan electron microscopy (SEM) images were collected by Rili SU 8000HSD series Hitachi new generation cold-field emission SEM. A combined

TE D

instrument of energy-dispersive spectrometer (EDS) was used for analyzing element and distribution. Thermo Gravimetric Analyzer (TG) and Differential Scanning Calorimetry (DSC) were conducted on PerkinElmer STA 6000 simultaneous thermal Analyzer at a

EP

heating rate of 10 ℃/minute under nitrogen atmosphere. X-ray photoelectron spectroscopy

AC C

(XPS) measurements were performed with ESCALAB 250Xi. The UV/Vis absorption spectra were recorded on PerkinElmer 750 spectrophotometer, and the BaSO4 powder was selected as the baseline correction material. An electrochemical workstation (Gamry INTERFACE 1000E) was used to detect the electrochemical properties of the samples. Steady-state photoluminescence (PL) measurements were performed using a FLS 920 luminescence spectrometer and the emission spectra were filtered with a 380 nm low-pass filter.

6

ACCEPTED MANUSCRIPT The current-voltage (I-V) measurements of photovoltaic devices were characterized using Gamry INTERFACE 1000E electrochemical workstation with an external bias potential under simulated sunlight with an intensity of 100 mWcm-2 at a scan rate of 20 mV s-1.

RI PT

Electrochemistry impedance spectroscopy (EIS) measurements were performed under AM 1.5G illumination at a frequency of 0.01-105 Hz with a bias voltage of 0 V using the Gamry INTERFACE 1000E electrochemical

workstation.

The incident

photon-to-electron

SC

conversion efficiency (IPCE) spectra were obtained with an IPCE measurement system and

M AN U

light intensity was calibrated by silicon detector (model 71675, Newport, USA).

3. Results and Discussion

In the synthesis process of AgBiSe2 (Scheme. 1), Bi(NO3)3 and AgNO3 were chosen as Bi3+ and Ag+ sources, and Se powder was used as anion source. The reaction equations are

Se s

(1) (2)

AC C

EP

AgN

N

TE D

shown as follows：

Scheme. 1 The synthesis of AgBiSe2 via a low temperature and aqueous solution route.

First of all, the influence of different heating time on the reaction (Eq. 1) was investigated (Fig. S1). When the reaction time increased from 1.5 to 2 h, the intensity of Se diffraction peak increased at 30°, exhibiting the possible decomposition of Na2SeSO3. As the reaction time increased to 2.5 h, the intensity of characteristic diffraction peak of AgBiSe2 was significantly weakened, indicating that the decomposition of Na2SeSO3 was more 7

ACCEPTED MANUSCRIPT serious, resulting in a sharp decrease in the product and a lower crystallinity. Owing to the thermal instability of Na2SeSO3, extended heating time appears detrimental to the success of the second step of the reaction. Therefore, the optimal reaction time should be deduced as 1 h to1.5 h.

RI PT

Next, the optimal ratio of AgNO3, Bi(NO3)3 and Na2SeSO3 to form AgBiSe2 was investigated. When the second reaction (Eq. 2) was carried out in a ratio of Ag:Bi:Se = 1:1:2, the appearance of Ag2Se impurities was observed and verified by XRD measurement. When

SC

the molar ratio of Ag to Bi decreased to 0.8, the diffraction peak of byproduct Ag2Se near 35° disappeared (Fig. S2). Finally, powder XRD pattern of the optimized product (Fig. 1(a))

M AN U

matched well with the standard card of a hexagonal phase of AgBiSe2 (PDF#29-1441).[6] The XRD result indicates that AgBiSe2 is successfully synthesized in an aqueous solution under a

AC C

EP

TE D

low temperature.

Fig. 1 (a) XRD patterns for AgBiSe2 nanoparticles. (b) TG-DSC patterns for AgBiSe2 nanoparticles.

Fig. 1(b) shows the TG-DSC curves of the as-synthesized AgBiSe2 composites. Clearly, the weight of powder does not significantly change before 700 ℃, indicating the good thermal stability of AgBiSe2. Besides, the DSC curve begin to drop at 700 ℃ and show the decomposition of sample, which corresponding to the TG curve. Furthermore, it can be observed that the DSC curve decreases at 300 ℃, as a result of the crystal transformation of

8

ACCEPTED MANUSCRIPT sample.[26] The above-analyzed results confirm that the product presents purity and high

SC

RI PT

thermal stability, which is benefit to the photoelectric energy conversion devices.

Fig. 2 (a) SEM image for AgBiSe2 sample. (b) EDS spectrum for AgBiSe2 sample

M AN U

In order to check the morphology of as-synthesized AgBiSe2 composites, the SEM and EDS measurements were carried out. As shown in Fig. 2(a), it is clearly seen that the size of AgBiSe2 ranges from 70-100 nm, and the majority of nanocrystals are with a particle size of ~80 nm. Compared with the solid sintering method, the product synthesized by a solution

TE D

method is directly nano-sized particles (Fig. S3). Apparently, their optical and thermal

AC C

EP

properties should be improved by the nano-effects of as-synthesized compound.

Fig. 3. (a) XPS spectrum for AgBiSe2 sample. (b), (c), (d) The XPS patterns of Ag 3d5/2 and Ag 3d3/2, Bi 4f7/2 and Bi 4f5/2, Se 3d5/2 and Se 3d3/2. 9

ACCEPTED MANUSCRIPT The X-ray photoelectron spectroscopy (XPS) analysis was performed to investigate the composition of as-prepared AgBiSe2 composites. As shown in Fig. 3, the peaks at 367 and 373 eV are attributed to Ag 3d5/2 and Ag 3d3/2, respectively. Besides, the binding energies of

RI PT

Bi 4f7/2 and Bi 4f5/2 located at 157.5 and 162 eV, respectively. The binding energies of Se 3d5/2 and Se 3d3/2 are observed at 52 and 53 eV, respectively.[19] Therefore, the elemental composition and valence state of the elements of as-synthesized AgBiSe2 composites were

TE D

M AN U

SC

confirmed by the XPS result.

EP

Fig. 4. (a) UV/Vis absorption for AgBiSe2 composites. (b) UPS survey spectrum for AgBiSe2 composites.

Furthermore, the UV/Vis absorption measurement was performed to study the optical

AC C

properties. As shown in Fig. 4(a), the absorption of AgBiSe2 composites has a very wide range from 300 to 1200 nm and high absorption intensity at 400-800 nm, indicating a narrow bandgap about 0.84 eV (Fig. S4). The excellent visible light absorption of AgBiSe2 composites will lead to an efficient utilization of sunlight and substantial potential in the photoelectric applications. In order to calculate its valence position, the ultraviolet photoelectron spectroscopy (UPS) of the AgBiSe2 composites has been detected, and the result was shown in Fig. 4(b). According to the formula: 10

ACCEPTED MANUSCRIPT E VBM " hν % ECucoff % EFermi

(3)

where EFermi is Fermi edge calculus in the UPS test curve, ECucoff is intersection of the line fitted by the cutoff edge with the baseline or the midpoint of the cutoff edge, hν is a constant of 21.22 eV.[32] It can be calculated that the valence band position of AgBiSe2 is -5.85 eV. In

RI PT

combine with bandgap and valence band, conduction band are calculated to be -5.01 eV. AgBiSe2 film was prepared by evaporation under vacuum of 10-4 Pa at a current program

SC

of 0.5 Å s-1 and applied to thin film. It is well known that the quality of film has a great influence upon device performance. Thus, a series of experiments were carried out to

M AN U

optimize the film quality, including film thickness, annealing temperature and annealing time length. First of all, the effect of film thickness on the light absorption behavior was explored. As displayed in Fig. 5(a), the film thickness has an influence upon the absorption intensity of the AgBiSe2. It can be observed that when the film thickness was 400 nm, the film presents

AC C

EP

TE D

the strongest light absorption intensity.

Fig. 5 UV/Vis absorption for AgBiSe2 film. (a) under different film thickness. (b) under different annealing temperature. (c) under different annealing time.

In order to improve the photoelectric properties of the film, the film had been annealed to improve the surface morphology. Annealing conditions of the film had been studied, and results were shown in Fig. 5(b) and (c). After the annealing treatment, all of the AgBiSe2

11

ACCEPTED MANUSCRIPT films have a strong absorption under the visible light area. SEM was further carried out to analyze the causes of changes in absorbance in the UV/Vis test results, as the heating temperature was increased from 100 °C to 120 °C, the surface of the AgBiSe2 film become

RI PT

smoother and denser, and no obvious cracks could be observed (Fig. S5). The good morphology can reduce defect inside the film and suppress the recombination between carriers effectively.

SC

After annealing treatment, the film exhibits a great potential in the separation and

M AN U

transport of electrons and holes. When the temperature further increased, irregular crystal grains began to appear on the surface of the AgBiSe2 film, defects on the surface of the film increased and caused the bad light absorption. Similarly, the regular uniform crystals appeared on the surface of the AgBiSe2 film after 100 minutes annealing treatment, and the

TE D

high crystallinity of the particles are suitable for the transportation of carriers (Fig. S6). As shown in Fig. 6(a), after annealing under the optimal parameters (120 °C, 100 minutes), the AgBiSe2 film has a significant improvement on the light absorption intensity under the

EP

wavelength range of 300-800 nm. In addition, the surface morphology of the AgBiSe2 film

AC C

has also been greatly improved (Fig. 6(b) and (c)). The surface of annealed AgBiSe2 film changes to smooth and flat, and regular small crystals appear, which could reduce the formation of defects and avoid the recombination of electrons and holes. In order to further understand what caused the improved performance of the annealed films, the EDS and XPS were carried out. As shown in Fig. S7-9, the elemental composition and valence of the film did not change, which consistent with the XRD test (Fig. S10) of AgBiSe2 film after annealing treatment. The above tests all indicate that the annealing treatment does help to

12

ACCEPTED MANUSCRIPT improve the transmission capacity of the carriers by improving the defect state on the surface

RI PT

of the film.[33]

SC

Fig. 6 (a) UV/Vis absorption for AgBiSe2 film, annealing parameters: 120 °C, 100 minutes. SEM images

M AN U

of the surface for AgBiSe2 film. (b) without annealing treatment, (c) with annealing treatment (120 °C, 100 minutes).

The steady-state photoluminescence (PL) of AgBiSe2 film was also investigated (Fig. 7a). Under the excitation wavelength at 380 nm, the AgBiSe2 film shows an obvious emission

TE D

peak at 430 nm. The emission intensity of the AgBiSe2 film exhibits a significant enhancement after annealing, which can be attributed to the reduction of non-radiative recombination in the surface. The result is consistent with the previous UV/Vis test and SEM

EP

test results. Overall, annealing process can improve the film morphology and reduce the

AC C

defects in the device, thereby suppressing the recombination of holes and electrons and promoting the transportation of carriers.[34]

13

ACCEPTED MANUSCRIPT Fig. 7 (a) PL spectra for AgBiSe2 film (excitation wavelength: 380 nm, annealing parameters:120 °C, 100 minutes). (b) J-V curves for AgBiSe2 film.

For further checking the photoelectric response of the AgBiSe2 film, we fabricated a

RI PT

device by sandwiching the AgBiSe2 films between the FTO films. Then the device was characterized by the I-V measurement under AM 1.5 G simulated one sun light. Fig. 7(b) shows the J-V curves of the AgBiSe2 films. Then, we calculated the resistivity of films using

/

3

" 1 " 24

(4)

M AN U

0

SC

the following equation:

where U represents the voltage (V), I represents the current (A), L represents the length (m), S represents the surface area (m2), P represents the resistivity (Ω*m). It should be noted that the area of the AgBiSe2 film are constantly defined by the area of etched FTO layer. The

TE D

resistivity of the AgBiSe2 film with annealing treatment was calculated as 0.53 Ω*m. On the contrary, the AgBiSe2 film without annealing is 0.57 Ω*m. The lower resistivity will facilitate

AC C

EP

electron transport inside the device.

Fig. 8 (a) EIS spectra for AgBiSe2 film. (b) IPCE spectra for AgBiSe2 film.

The EIS and IPCE measurements were performed in order to study the electrochemical performances of the device. As shown in Fig. 8(a), the circle can be belonged to charge

14

ACCEPTED MANUSCRIPT transfer at FTO/AgBiSe2 film interfaces. After annealing treatment, the half located at 90 to 120 KΩ cm-2 of the curve shrank significantly, indicating the reduced transmission resistance. The annealing treatment improved the morphology of the film and made it advantageous for

RI PT

the transportation of carriers should be the possible reason.[35] The IPCE spectra are shown in Fig. 8(b), the monochromatic light absorption efficiency of the film, especially between 450 and 700 nm in the visible light area, has been further improved after annealing treatment. It

SC

proves that the annealing treatment is attributed to the enhancement in the interfacial

M AN U

optoelectronic properties.[36] Therefore, the transmission efficiency of carriers between the interfaces and the absorption intensity of light can be improved after AgBiSe2 composites doped in the devices.

4. Conclusion

TE D

In summary, the AgBiSe2 nanoparticles were successfully synthesized by a facile solution method under a low temperature, which is quite suitable for the construction of thin film photovoltaic devices. AgBiSe2 shows a granular shape with a diameter of ca. 80 nm.

EP

More importantly, AgBiSe2 features an excellent light absorbance in the whole UV/Vis region,

AC C

which is a prominent characteristic for its photovoltaic application. In addition, fluorescence emission intensity of AgBiSe2 film can be effectively enhanced after heating treatment at a suitable temperature condition, proving that annealing can improve the crystallinity of nanoparticles and change the morphology of film. Finally, EIS and IPCE results support the enhancement of photoelectric conversion efficiency and the interfacial transport of charge carriers after annealing treatment. This facile method may facilitate the development of high-performance photovoltaic devices based on ternary semiconductors.

15

ACCEPTED MANUSCRIPT

Acknowledgements This work is supported by National Natural Science Foundation of China (Grant No. 21873025, 21571042, 21371040, and 51603055), the Natural Science Foundation of

RI PT

Heilongjiang Province (Grant No. QC2017055), the China Postdoctoral Science Foundation (Grant No. 2016M601424, 2017T100236), the Postdoctoral Foundation of Heilongjiang

SC

Province (Grant No. LBH-Z16059).

References

M AN U

[1] Y. Liu, Y. Zhang, Z. Yang, J. Feng, Z. Xu, Q. Li, M. Hu, H. Ye, X. Zhang, M. Liu, K. Zhao, S. Liu, Low-temperature-gradient crystallization for multi-inch high-quality perovskite single crystals for record performance photodetectors, Mater. Today 22 (2019) 67-75. [2] J. Li, Y. Pan, C. Wu, F. Sun, T. Wei, Processing of advanced thermoelectric materials, Sci. China: Technol. Sci. 60(9) (2017) 1347-1364.

TE D

[3] N. Li, Z. Lan, L. Cai, F. Zhu, Advances in solution-processable near-infrared phototransistors, J. Mater. Chem. C 7(13) (2019) 3711-3729. [4] T.-R. Wei, C.-F. Wu, F. Li, J.-F. Li, Low-cost and environmentally benign selenides as

EP

promising thermoelectric materials, Journal of Materiomics 4(4) (2018) 304-320. [5] A. Tabeti, M. Batouche, K. Bidai, A. Djied, T. Seddik, R. Khenata, H. Baltach, X. Wang, DFT investigation on the electronic and thermoelectric properties of ternary semiconductor

AC C

AgBiS2 for energy conversion application, Chin. J. Phys. 59 (2019) 578-584. [6] F. Böcher, S.P. Culver, J. Peilstöcker, K.S. Weldert, W.G. Zeier, Vacancy and anti-site disorder scattering in AgBiSe2 thermoelectrics, Dalton Trans. 46(12) (2017) 3906-3914. [7] Z. Tiejun, L. Yintu, F. Chenguang, H.J. P., S.J. G., Z. Xinbing, Compromise and synergy in high-efficiency thermoelectric materials, Adv. Mater 29(14) (2017) 1605884. [8] M.D. Nielsen, V. Ozolins, J.P. Heremans, Lone pair electrons minimize lattice thermal conductivity, Energy Environ. Sci. 6(2) (2013) 570-578. [9] Y. Zhang, G.D. Stucky, Heterostructured approaches to efficient thermoelectric materials, Chem. Mater. 26(1) (2014) 837-848. 16

ACCEPTED MANUSCRIPT [10] K. Hoang, S.D. Mahanti, Atomic and electronic structures of I-V-VI2 ternary chalcogenides, Journal of Science: Advanced Materials and Devices 1(1) (2016) 51-56. [11] M. Dutta, K. Pal, U.V. Waghmare, K. Biswas, Bonding heterogeneity and lone pair induced anharmonicity resulted in ultralow thermal conductivity and promising

RI PT

thermoelectric properties in n-type AgPbBiSe3, Chem. Sci. (2019) 10, 4905-4913 [12] Y. Goto, A. Nishida, H. Nishiate, M. Murata, C.H. Lee, A. Miura, C. Moriyoshi, Y. Kuroiwa, Y. Mizuguchi, Effect of Te substitution on crystal structure and transport properties of AgBiSe2 thermoelectric material, Dalton Trans. 47(8) (2018) 2575-2580.

SC

[13] F. Heinke, F. Nietschke, C. Fraunhofer, I. Dovgaliuk, J. Schiller, O. Oeckler, Structure and thermoelectric properties of the silver lead bismuth selenides Ag5Pb9Bi19Se40 and

M AN U

AgPb3Bi7Se14, Dalton Trans. 47(35) (2018) 12431-12438.

[14] T. Bernges, J. Peilstöcker, M. Dutta, S. Ohno, S.P. Culver, K. Biswas, W.G. Zeier, Local structure and influence of Sb substitution on the structure-transport properties in AgBiSe2, Inorg. Chem. (2019) 58 14 9236-9245.

[15] A. Das, A. Shamirian, P.T. Snee, Arsenic Silylamide: An effective precursor for arsenide

TE D

semiconductor nanocrystal synthesis, Chem. Mater. 28(11) (2016) 4058-4064. [16] L. Mehdaoui, R. Miloua, M. Khadraoui, M.O. Bensaid, D. Abdelkader, F. Chiker, A. Bouzidi, Theoretical analysis of electronic, optical, photovoltaic and thermoelectric

EP

properties of AgBiS2, Phys. B, 564 (2019) 114-124. [17] T. Xing, R. Liu, F. Hao, P. Qiu, D. Ren, X. Shi, L. Chen, Suppressed intrinsic excitation and enhanced thermoelectric performance in AgxBi0.5Sb1.5−xTe3, J. Mater. Chem. C 5(47)

AC C

(2017) 12619-12628.

[18] S.N. Guin, S. Banerjee, D. Sanyal, S.K. Pati, K. Biswas, Nanoscale stabilization of nonequilibrium rock salt BiAgSeS: colloidal synthesis and temperature driven unusual phase transition, Chem. Mater. 29(8) (2017) 3769-3777. [19] A. Das, B. Hsu, A. Shamirian, Z. Yang, P.T. Snee, Synthesis of high-quality AgSbSe2 and AgBiSe2 nanocrystals with antimony and bismuth silylamide reagents, Chem. Mater. 29(10) (2017) 4597-4602. [20] M. Liu, P.D. Spanos, S.-H. Yu, Synthesis of ultrathin Bi2Se3 nanosheets/graphene nanocomposite with defects/vacancies-dependent transient photocurrent performance, Nano 17

ACCEPTED MANUSCRIPT Energy, (2019) 103877. [21] J. Moon, J. Kim, N. Koirala, M. Salehi, D. Vanderbilt, S. Oh, Ferromagnetic anomalous hall effect in Cr-doped Bi2Se3 thin films via surface-state engineering, Nano Lett. 19(6) (2019) 3409-3414.

RI PT

[22] S. Gupta, D.C. Agarwal, B. Sivaiah, S. Amrithpandian, K. Asokan, A. Dhar, B.K. Panigrahi, D.K. Avasthi, V. Gupta, Enhancement in thermoelectric properties due to Ag nanoparticles incorporated in Bi2Te3 matrix, Beilstein J. Nanotechnol. 10 (2019) 634-643. [23] M.-P. Lu, C.-N. Liao, J.-Y. Huang, H.-C. Hsu, Thermoelectric properties of Ag-doped

SC

Bi2(Se,Te)3 compounds: dual electronic nature of Ag-related lattice defects, Inorg. Chem. 54(15) (2015) 7438-7444.

M AN U

[24] S. Figueroa-Millon, I. Álvarez-Serrano, D. Bérardan, A. Galdámez, Synthesis and transport properties of p -type lead-free AgSnmSbSe2Tem thermoelectric systems, Mater. Chem. Phys. 211 (2018) 321-328.

[25] S.N. Guin, D.S. Negi, R. Datta, K. Biswas, Nanostructuring carrier engineering and bond anharmonicity synergistically boost the thermoelectric performance of p-type

TE D

AgSbSe2-ZnSe, J. Mater. Chem. A 2(12) (2014) 4324.

[26] L. Pan, D. Bérardan, N. Dragoe, High thermoelectric properties of n-Type AgBiSe2, J. Am. Chem. Soc. 135(13) (2013) 4914-4917.

EP

[27] T. Manimozhi, J. Archana, M. Navaneethan, K. Ramamurthi, Shape-controlled synthesis of AgBiS2 nano/microstructures using PEG-assisted facile solvothermal method and their functional properties, Appl. Surf. Sci. 487 (2019) 664-673.

AC C

[28] D.J. Xiaocun Liu, and Xin Liang, Enhanced Thermoelectric performance of n-Type transformable AgBiSe2 polymorphs by indium doping, Appl. Phys. Lett., (2016), 109 133901. [29] L. Xinsheng, C. Chao, W. Liang, Z. Jie, L. Miao, C. Jie, X. Ding-Jiang, L. Dengbing, Z. Ying, T. Jiang, Improving the performance of Sb2Se3 thin film solar cells over 4% by controlled addition of oxygen during film deposition, Prog Photovolt Res Appl. 23(12) (2015) 1828-1836. [30] D.-J. Xue, S.-C. Liu, C.-M. Dai, S. Chen, C. He, L. Zhao, J.-S. Hu, L.-J. Wan, GeSe thin-film solar cells fabricated by self-regulated rapid thermal sublimation, J. Am. Chem. Soc. 139(2) (2017) 958-965. 18

ACCEPTED MANUSCRIPT [31] T.A. Hameed, A.R. Wassel, I.M. El Radaf, Investigating the effect of thickness on the structural, morphological, optical and electrical properties of AgBiSe2 thin films, J. Alloys Compd. (2019) 805 1-11. [32] H. Luo, J. Wu, X. Liu, Y. Yang, Q. Liu, M. Zhang, P. Yuan, W. Sun, Z. Lan, J. Lin,

RI PT

Thiourea interfacial modification for highly efficient planar perovskite solar cells, ACS Appl. Energy Mater. 1(12) (2018) 6700-6706.

[33] T.H. Han, S. Tan, J. Xue, L. Meng, J.W. Lee, Y. Yang, Interface and defect engineering for metal halide perovskite optoelectronic devices, Adv. Mater. (2019) 1803515.

SC

[34] B. Xu, Z. Zhu, J. Zhang, H. Liu, C.-C. Chueh, X. Li, A.K.Y. Jen, 4-Tert-butylpyridine free organic hole transporting materials for stable and efficient planar perovskite solar cells,

M AN U

Adv. Energy Mater. 7(19) (2017) 1700683.

[35] X. Yin, P. Chen, M. Que, Y. Xing, W. Que, C. Niu, J. Shao, Highly efficient flexible perovskite solar cells using solution-derived NiOx hole contacts, ACS nano 10(3) (2016) 3630-6.

[36] Y.H. Choi, H.B. Kim, I.S. Yang, S.D. Sung, Y.S. Choi, J. Kim, W.I. Lee, Silicotungstate,

TE D

a potential electron transporting layer for low-temperature perovskite solar cells, ACS Appl.

AC C

EP

Mater. Interfaces 9(30) (2017) 25257-25264.

19

ACCEPTED MANUSCRIPT 1. AgBiSe2 was

prepared

via

a

facile

synthesis

route

under

a

lower

temperature(~373K). 2. High quality nanomaterials with good crystallinity were synthesized. 3. AgBiSe2-based devices exhibit a reduced resistance of 0.53 Ω*m and markedly 50%

AC C

EP

TE D

M AN U

SC

RI PT

improved absorption efficiency after annealing treatment.