Applications In Photovoltaic Devices Research Articles

GeC/SiCx van der Waals heterojunction: Applications for water splitting and solar cell

We construct GeC/SiCx(x = 1,2,7) van der Waals heterojunctions to study the photoelectric properties. The first-principle calculations show that three heterojunctions have the Z-type band alignment by analyzing the charge transfer paths. The designed heterojunctions possess good optical absorption in the visible light region, suggesting potential applications in photocatalysis, solar cells, and other photovoltaic devices. It is found that GeC/SiC and GeC/SiC7 heterojunctions fulfill the requirements as photocatalysts from PH = 0 to PH = 14. Although the GeC/SiC2 heterojunction fulfills the requirements as a photocatalyst from PH = 6 to PH = 10, the GeC/SiC2-based solar cell presents excellent performance, whose power conversion efficiency reaches 24.6 % theoretically. The results demonstrate that GeC/SiCx (x = 1, 2, 7) is a potential candidate for photocatalytic and solar cell materials in the future.

Ag decorated V2O5 electrodes as a promising option for electrochromic, photovoltaic, and energy-saving applications

This study reports the fabrication of electrochromic Ag decorated V2O5 thin film by thermal evaporation method at 10−5 torr vacuum medium and the effects of the Ag doping to the V2O5 matrix. Besides, the electrochromic capabilities and energy-saving characteristics of the films are also in the scope of this study. Structural and morphological properties are investigated by XRD, FESEM, and AFM. The films have a polycrystalline structure and a porous surface. FTIR and Raman spectra verify the molecular formation of the films. The performance of the electrochromic films is characterized by a variety of techniques such as cyclic voltammetry, chronoamperometry, chronocolumetry, and electrochemical impedance spectroscopy. The color of the films changes from yellow to green and then from green to blue in the range of −1.2 and + 1.0 V vs Ag/AgCl with a reversibility of 92.9 %. With the response times of tb = 13.6 s and tc = 9.4 s, an optical modulation of 51.7 % (from yellow to blue), and a coloration efficiency of 93.7 cm2 C−1, Ag:V2O5 becomes an impressive electrochromic material produced by physical methods. Linear sweep voltammetry studies show that the photocurrent of both V2O5/ITO and Ag:V2O5/ITO electrodes increases under solar illumination. The supercapacitive performance of the film is investigated by cyclic voltammetry, and Ag:V2O5 is an encouraging electrode material with a specific capacitance of 720.9 F g−1 at 5 mV s−1 scan rate. An equivalent circuit is fitted from the film Nyquist data and the results also confirm the positive contribution of Ag doping on the response times, energy saving, and photoresponse of V2O5 thin film. In this regard, the produced electrodes are highly promising for potential applications in electrochromic, energy storage, and photovoltaic devices.

Exploring the influence of iron doping on structural, morphological and optical properties of chemical bath deposited cadmium selenide thin films for optoelectronic applications

This research investigates the structural, morphological, and optical properties of Cadmium Selenide (CdSe) thin films deposited via the Chemical Bath Deposition (CBD) Technique, focusing on the impact of Iron (Fe) doping. Using Cadmium Chloride (CdCl2) and Ferrous chloride (FeCl2) as precursor materials, the research investigates how Fe doping affects the structural and photoelectric characteristics of the films. Employing various characterization methods including X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), and UV–Vis NIR spectroscopy, the study provides a comprehensive analysis of the films. XRD analysis confirms the formation of a cubic structure with a predominant orientation along the (111) plane, consistent with XRD peaks. Additionally, XRD data reveals the degradation of thin films post-annealing. Crystalline size and strain are determined using the Debye-Scherrer and Wilson formulae, while lattice constant and Size-strain plots are derived from X-ray line broadening. The average crystallite size ranges from 12 to 21 nm. Optical band gaps are found to be 2.25 eV, 2.91 eV, 2.87 eV, and 2.85 eV for the samples. Interestingly, a decrease in crystal size with increasing doping concentration correlates with a reduction in bandgap. This investigation offers valuable insights into the fabrication and characterization of CdSe thin films, particularly highlighting the impact of Fe doping on their structural and optical properties. Overall, this study provides valuable insights into the fabrication and characterization of CdSe thin films, emphasizing the importance of precise doping control for tailoring material properties and advancing their applications in photovoltaic and optoelectronic devices.

First-principles study of Na2AgAsZ6 (Z = F, Cl, Br, I) of structural, elastic, optoelectronic, and transport properties of lead-free halide double perovskites for energy conversion applications

In this article, density functional theory (DFT) is used to investigate the physical aspects of the halide double perovskites Na2AgAsZ6 (Z = F, Cl, Br, I). These substances have a cubic arrangement and are classified under space group Fm3m (225) based on their octahedral and tolerance factors values. All the perovskites are determined to be thermodynamically stable, as indicated by their negative formation energy. These double perovskite materials are semiconductors based on their electronic band structure. The energy band gaps of Na2AgAsF6, Na2AgAsCl6, Na2AgAsBr6, and Na2AgAsI6 were determined to be 2.96 eV, 1.93 eV, 1.28 eV, and 0.68 eV, respectively. We also calculated and examined the optical properties of these substances in the photon energy range of 0–8 eV. Our results indicate that the majority of the absorption occurs in the visible-ultraviolet spectrum, which makes the materials well-suited for solar systems. We employed the BoltzTraP algorithm to compute the thermoelectric properties of the materials and establish their thermoelectric behavior. These materials demonstrated figures of merit values of 0.55, 0.71, 0.74, and 0.75, respectively. Thus, these materials are appropriate for application in photovoltaic and thermoelectric devices.

Ab initio calculation of electronic and optical properties of vdWHs HfX2/BSb(X = Se,S) using density functional theory

Recently, another series of two-dimensional (2D) materials called van der Waals heterostructures (vdWhs) have attracted a lot of attention due to their outstanding properties and wide application in electronic and optical devices. Based on density functional theory (DFT) calculations, the properties of heterostructures were investigated with two different vertical arrangements, formed by two isolated sheets of HfX2(X = Se,S) and Boron antimonide(BSb) monolayer. In particular, vdW interactions are present in all these heterostructures rather than covalent bonding. All thevdWHsare semiconductor with indirect k-M band gap, for which the HSE06 functional exhibit a larger gap, but the electronic gap of all heterostructures is smaller than the electronic gap of their constituent sheets. In addition, all vdWHs show excellent optical absorption in the visible, near-infrared, and ultraviolet regions in the x direction, while the absorption peaks for all vdWHs are higher in the z direction. By fabricating heterostructures from isolated plates, their absorption power increases. The present review demonstrates an effective method for the design of novel vdWHs, and it explores their applications for photocatalytic, photovoltaic, and optical devices.

Pressure action on ductility and optoelectronic properties of non-toxic AGeBr[formula omitted] (A = Cs, K, Na, Rb) perovskites

We performed first-principles calculations base on generalized gradient approximation(GGA) in the framework of density functional theory (DFT) to examine the effect of pressure on the structural, mechanical, electronic and optical properties of non-toxic AGeBr3 perovskites (A = Cs, K, Na, Rb) for applications in photovoltaic and optoelectronic devices. The dependence of physical properties is evaluated for several pressure values ranging from 0 GPa to 10 GPa. The determined lattice parameters show agreement with previous values and decrease with the applied pressure. All considered materials show semiconductor behavior with direct bandgap (R ⟶ R) at atmospheric pressure. The hybrid functionals HSE and PBE0 have been used to determine accurate values for bandgaps. A very good agreement was found with available experimental values. The calculated bandgap values were found to be 2.129 [2.608] for CsGeBr3, 2.065 [2.481] for KGeBr3, 2.032 [2.397] for NaGeBr3 and 2.089 [2.530] for RbGeBr3, at the HSE [PBE0] level of theory. However, as the applied pressure increases, a reduction in the bandgap is observed, leading to semiconductor to metallic transition. The materials similarly show improved optical properties under pressure with high absorption coefficients in the visible and ultraviolet regions. In addition, the ductility and stability of the considered materials were found also to improve under hydrostatic pressure, which makes them suitable for incorporation into thin films for high performance optoelectronic devices application.

An extensive study on charge transport layers to design and optimization of high-efficiency lead-free Cs2PtI6-based double-perovskite solar cells: A numerical simulation approach

Perovskite materials are getting attention day by day due to their numerous optoelectronic properties. Lead-free perovskites are well-known for various applications in photovoltaic devices due to their non-toxicity which has no impacts on both the environment and health. Cs2PtI6, a lead-free halide perovskite, is renowned for its broad-spectrum light absorption and remarkably high absorption coefficient. Its stability under ambient conditions surpasses that of numerous other halide perovskites, rendering it exceptionally appealing for photovoltaic applications. The device configuration with FTO/ETL/Cs2PtI6/HTL/Au is used in this study where 4 different ETLs and 10 HTLs are used to investigate the best device configuration. The impact of different device parameters like thickness, acceptor density, donor density, and defect density are optimized to attain the best efficient device configuration. SCAPS-1D simulator is used to perform numerical analysis under light intensity of AM 1.5 light spectrum (100 mW/cm2). After the optimization of different device parameters, the device configured with FTO/SnS2/Cs2PtI6/MoTe2/Au shows the best performance among four devices where PCE is 32.98 %, VOC is 1.11 V, JSC is 33.19 mA/cm2, FF is 88.89 %. This suggested Cs2PtI6-based perovskite solar cells demonstrate superior performance compared to numerous lead perovskite-based solar cells, highlighting Cs2PtI6 as a promising alternative for photovoltaic applications while mitigating toxicity concerns.

First principle calculations to explore the electronic, mechanical and optical properties of 2D NiX2 (X = O, S, Se) monolayers

This investigation employs ab-initio calculations to investigate the structural, dynamical, mechanical, and optoelectronic attributes of 1T-NiX2 (X = O, S, Se) monolayers. The confirmation of structural and dynamical stability is derived from negative cohesive energy values and the absence of negative frequencies in phonon dispersion spectra. Mechanical stability is established through the application of the Born-Huang stability criterion. Results indicate that an increase in the X-atom size from O to Se induces a reduction in material stiffness from 137.64 Nm−1 to 77.56 Nm−1 and thus, enhances the flexibility of the monolayers. The NiX2 monolayers exhibit indirect bandgap features with values 1.33 eV (1.81 eV), 0.63 eV (0.61 eV) and 0.28 eV (0.28 eV) using PBE (PBE+U) methods. Present results show an inverse relations between the band gap and the size of the X atom. The scanning tunnelling microscope (STM) images of 2D NiX2 monolayers are also simulated for experimental observations. Additionally, exploration of optical characteristics reveals high optical absorption (105 cm−1), which lies from infrared to UV-region. Moreover, NiO2 can be utilized as good wave anti-reflectors with reflection of incident light less than 7%. These results suggest NiX2 materials as promising candidates for diverse applications in optoelectronic and photovoltaic devices.

2D Janus ZrSSe/SnSSe Heterostructure: A Promising Candidate for Photocatalytic Water Splitting.

The distinctive physical characteristics and wide range of potential applications in optoelectronic and photovoltaic devices have ignited significant interest in two-dimensional materials. Intensive research attention has been focused on Janus transition metal dichalcogenides due to their unique properties resulting from symmetry disruption and their potential in photocatalysis applications. Motivated by the current fascination with Janus TMD heterostructures, we conducted first-principles calculations to examine the stability, electronic, and optical properties of monolayers consisting of ZrSSe, SnSSe, and the ZrSSe/SnSSe heterostructure. The results indicate that the Janus ZrSSe/SnSSe heterostructure exhibits a structural and mechanical stability. Using the HSE06 functional, the ZrSSe/SnSSe heterostructure shows an indirect band gap of 1.20 eV, and band edge analysis reveals a type-II band alignment. The potential for photo/electrocatalysis in the ZrSSe/SnSSe heterostructure for water splitting or generating reactive oxygen species (ROS) has been explored, and it was found that the oxygen evolution reaction (OER) can spontaneously activate in acidic (pH = 0) media under light irradiation, with a potential of U = 1.82 eV. Additionally, the ZrSSe/SnSSe heterostructure exhibits strong light absorption across a wide range, from visible light to the ultraviolet region, at various levels. These findings open up possibilities for the application of ZrSSe/SnSSe-based materials in optoelectronic devices.

Optoelectronic properties, stability, and thermodynamic properties of 2D XSn2N4 (X = Cr, Mo, W) monolayers

Through first-principle calculations, we show innovative CrSn2N4, MoSn2N4 and WSn2N4 monolayers with high stability. The current results reveal that CrSn2N4 is a conductor-like material with metallic propensity, while MoSn2N4 and WSn2N4 are indirect bandgap semiconductors with narrow bandgaps of 0.16 eV and 0.39 eV, respectively. The mechanical characteristics of CrSn2N4, MoSn2N4, and WSn2N4 are stable, with Young's modulus and Poisson's ratio greater than those of graphene and C2F4. Besides, the thermodynamic characteristics were tested, and it was observed that the thermodynamic stability of MoSn2N4 was superior to the other two materials. The optical properties show the layered MoSn2N4 and WSn2N4 have strong light absorption and a wide absorption range, which have the potential for application in photovoltaic cells and devices. The spectral limits of the maximum efficiencies of 22 % and 14 % for MoSn2N4 and WSn2N4, respectively, are greater than those of SnO2. Thus, the three novel two-dimensional materials have potential applications in the area of photoelectric devices.

Effect of mild mechanical stresses on device physics of slot-die coated flexible perovskite solar cells

Halide perovskites are a promising class of novel photoactive materials for their application in flexible photovoltaic devices. Tolerance and stability of devices to various mechanical stresses are important aspects of this technology for its effective and long-term operation. Currently, this aspect has not been fully researched and addressed by the research community. Hence, this work is aimed at studying the effect of mild mechanical stresses (MMSs) induced by convex bending on the behaviour of ITO/ZnO/MAPbI3/Spiro-OMeTAD/Au slot-die-coated flexible perovskite solar cells (FPSCs) and investigating the underlying mechanisms leading to performance degradation in devices. The carrier generation, recombination, and extraction processes within FPSCs are investigated before and after the application of MMSs. The obtained results suggest that the photovoltaic performance of the FPSCs deteriorates by up to 50% after convex bending, due to increased non-radiative recombination losses. The results obtained in this work provide some valuable insights into the dynamics of recombination processes in FPSCs exposed to MMSs and can be used for developing new strategies for improving the mechanical stability of devices.

Real-Time Ab Initio Investigation on Hot Electron Relaxation Dynamics in Silicon.

The relaxation of hot electrons in semiconductors is pivotal for both energy harvesting processes and optoelectronics. Utilizing a self-developed non-adiabatic molecular dynamics simulation approach in the momentum space (NAMD_k), we have examined the dynamics of hot electrons in silicon. Whether excited from the Γ or L point, the relaxation dynamics exhibit two distinct stages. Initially, within 100 fs, electrons scatter with phonons throughout the Brillouin zone. Subsequently, over a few picoseconds, they further relax toward the conduction band minimum as a whole. This picture of hot electron relaxation is highly consistent with the quasi-equilibrium hot electron ensemble (HEE) concept. Throughout the hot electron relaxation process, energy transfer to phonons is efficient, leading to time-dependent phonon excitation, which is thoroughly analyzed. This investigation provides a novel perspective on hot electron relaxation in silicon, which holds substantive implications for the realm of photovoltaic and optoelectronic device applications.

Modified surface ligand management of CsPbI3 perovskite quantum dots enables efficient and stable electroluminescent solar cells

Solution-processed CsPbI3 perovskite quantum dots (PQDs) have attracted enormous attention in both photovoltaic and electroluminescent applications in recent years. However, the surface defects of CsPbI3 PQDs in the ligand exchange procedure still suffer the challenge of imperfect passivation, leading to poor device performance and ambient stability. In this work, we propose a modified surface ligand management to deposit CsPbI3 PQD films using a layer-by-layer (LBL) solid-state exchange strategy, and its applications in photovoltaic and electroluminescent devices are studied. The conjugated phenethylammonium iodide (PEAI) ligand, acting as a short-chain ligand with a phenyl group (PEA+ ion) for encapsulating the CsPbI3 PQDs during the LBL procedure, which can both realize enhanced inter-dot coupling and defects passivation compared with conventional post-treatments. We further demonstrate the balanced transport and injection of electrons and holes within the PEAI-LBL based CsPbI3 PQD films. With this approach, the CsPbI3 PQD solar cells based on PEAI-LBL yielded a champion power conversion efficiency (PCE) of up to 14.18% with a high open voltage of 1.23 V, along with obviously electroluminescent red emission properties in one device. Meanwhile, the unencapsulated devices exhibited excellent stability under a high-humidity environment. This strategy should accelerate advancement in utilizing PQDs for bifunctional optoelectronic applications.

Investigation of AcXO3 (X = Al, Ga) perovskites for energy harvesting applications: a DFT approach

Full potential linearized augmented plane wave (FP-LAPW) based computational study is presented for AcAlO3 and AcGaO3. Tolerance factor (τG) is 0.93 for AcAlO3 and 0.90 for AcGaO3 which reveal the stability of proposed perovskite oxides in cubic phase. The calculated band structures for both materials reveal the nonmagnetic semiconductive nature with energy band gaps of 3.98 and 2.75 eV for respective Al and Ga based perovskites. Total, and partial density of states (DOS) are computed for meaningful understanding of semiconducting behavior of the proposed perovskites. The partially filled O-2p and Ac-6d states are observed to lie in the vicinity of Fermi level. Furthermore, various parameters of optical spectra have also been computed to study the light matter interaction. Moreover, thermoelectric (TE) properties of both materials have been investigated by using semiclassical Boltzmann theory with constant relaxation time approximation. Calculated figure of merit (ZT) values for AcAlO3 and AcGaO3 are 0.23 and 0.20 at 800 K, respectively. Overall, computational study for titled perovskites indicate that these materials have application in UV sensors, photovoltaic and thermoelectric devices.

Structural, optical and electrical studies of non-toxic oxide- RMnO3 [R=Y, Er, Yb] hexagonal manganite thin-films

Recently, ferroelectric-photovoltaics have come under the spotlight as a potential class of materials for application in photovoltaic devices. However, the broad bandgap of these ferroelectric-photovoltaic materials causes them to have modest photocurrents[1]. To overcome this challenge hexamanganites can be used to achieve high photovoltaic efficiency as it has a small band gap. Here we present a stable, non-toxic, and cost-efficient hexamanganite RMnO3 [R=Y, Er, Yb] thin films prepared by spray pyrolysis method. The formation of the single phase is confirmed by X-ray diffraction analysis. Morphological studies show grains are uniform and closely packed and the grain size increases with the decrease in ionic radii of rare earth ions. A narrow optical band gap of nearly 1.5 eV is observed for the films. The results of this investigation show that Ultraviolet ray irradiation can be used to tune the bandgap. With a carrier concentration of around 10+14 cm−3, Hall measurements proved that the films are p-type semiconductors. This research illuminates the exploration of stable oxide semiconductors with a small band gap for applications in futuristic solar cells.

Flexibility potential of Cs2BX6 (B = Hf, Sn, Pt, Zr, Ti; X = I, Br, Cl) with application in photovoltaic devices and radiation detectors

As interest in double perovskites is growing, especially in applications like photovoltaic devices, understanding their mechanical properties is vital for device durability. Despite extensive exploration of structure and optical properties, research on mechanical aspects is limited. This article builds a vacancy-ordered double perovskite model, employing first-principles calculations to analyze mechanical, bonding, electronic, and optical properties. Results show Cs2HfI6, Cs2SnBr6, Cs2SnI6, and Cs2PtBr6 have Young's moduli below 13 GPa, indicating flexibility. Geometric parameters explain flexibility variations with the changes of B and X site composition. Bonding characteristic exploration reveals the influence of B and X site electronegativity on mechanical strength. Cs2SnBr6 and Cs2PtBr6 are suitable for solar cells, while Cs2HfI6 and Cs2TiCl6 show potential for semi-transparent solar cells. Optical property calculations highlight the high light absorption coefficients of up to 3.5×105 cm−1 for Cs2HfI6 and Cs2TiCl6. Solar cell simulation shows Cs2PtBr6 achieves 22.4% of conversion efficiency. Cs2ZrCl6 holds promise for ionizing radiation detection with its 3.68 eV bandgap and high absorption coefficient. Vacancy-ordered double perovskites offer superior flexibility, providing valuable insights for designing stable and flexible devices. This understanding enhances the development of functional devices based on these perovskites, especially for applications requiring high stability and flexibility.

Theoretical insights into the electronic and optical properties of lithium-based perovskite for solar cell applications

This study explores the influence of central metals and halide anions on the structural, electronic, and optical properties of LiBX3 perovskites (B = Ge, Sn, Pb, X = F, Cl, Br, I) in both unit cell and supercell configurations, aiming for potential applications in photovoltaic devices. Density functional theory calculations reveal that increasing the atomic radius of halogens and central metals directly affects the lattice parameters. Our research indicates that Ge and Sn-based perovskites (except for unit cell LiSnF3) exhibit semiconductor properties with direct band gap energies, while Pb-based perovskites in the unit cell configuration display an indirect band gap. Key factors contributing to the reduction of the band gap energy in most materials include the expansion of the atomic radius of halogens and the examination of perovskites in their supercell state, such that perovskites like LiGeI3, LiSnI3, and LiPbI3 represent a band gap value of 0.001 eV in their supercell configuration. Furthermore, the light absorption characteristics of these perovskites demonstrate a high absorption coefficient ranging from 105 to 106. Among the studied compounds, I-based perovskites exhibit the highest static dielectric constant, surpassing other perovskite variants, with for example, unit cell and supercell of LiSnI3 having static dielectric constant values of 38 and 70, respectively. Additionally, the investigation of perovskites in their supercell form suggests that the number of atoms in the network does not significantly impact their optical properties. In conclusion, based on various analyses, I-based perovskites are proposed as ideal candidates for application in Photovoltaic Solar Cells (PSCs).

Ultrafast Electron and Hole Transfer and Efficient Charge Separation in a Sb2Se3/CdS Thin Film p-n Heterojunction.

Harvesting solar energy for different applications requires the continuous development of new semiconducting materials to exploit a broad part of the solar spectrum. In this direction, antimony selenide (Sb2Se3) has attracted a tremendous amount of attention over the past few years as a light-harvesting material for photovoltaic device applications owing to its phase stability, high absorption coefficient, earth abundance, and low toxicity. Here, we have fabricated a high-quality heterojunction of a p-type Sb2Se3 film and an n-type CdS film using the thermal evaporation technique. The photocurrent of the heterosystem was significantly higher than that of the pristine materials. This optoelectronic response was investigated using femtosecond transient absorption (TA) spectroscopy. TA study reveals the existence of an instantaneous electron transfer from Sb2Se3 to CdS, accompanied by a substantial charge separation at the heterojunction. Our study deals with the investigation of a well-designed p-n device, paving the way for the fabrication of highly efficient photovoltaic devices.

The influence of laser-annealing pulse width on optical transparency and carrier dynamics of ITO thin films

Indium tin oxide (ITO) has important application in photoelectronic and photonic devices, demanding effective approach and appropriate parameters to modulate the ITO properties. The effects of laser annealing at 1064 nm with different pulse width (875 ps, 10 ns, and 300 ns) on optical and nonlinear optical properties of ITO films were investigated. Compared with 875 ps and 10 ns, laser annealing at 300 ns significantly improved the near-infrared transmittance of ITO films. The change arises from the elimination of oxygen vacancies and reduction of tin oxides, resulting in the decrease of carrier concentration. Finite element simulations indicate that laser annealing with pulse width of 875 ps and 10 ns have high instantaneous peak temperatures of 1128.5 K and 783 K, respectively, while the temperature accumulation between pulses is negligible. On the contrary, the laser annealing with a pulse width of 300 nshas lower peak transient temperature of 343 K but high static residence temperature of 973 K. The results reveal that the modification of ITO films depends more on the static average temperature rather than the instantaneous peak temperature. The modulation of carrier dynamics in both amplitude and temporal domain was demonstrated after 300 ns laser annealing, achieving ultrafast transient response approximately 150 fs. This work provides theoretical and experimental basis for us to select suitable laser conditions for directional annealing of ITO film to make it suitable for the applications of broad optical spectrum photovoltaic devices or ultrafast optical exchange for high-speed data processing.

Intercorrelated Ferroelectricity and Bulk Photovoltaic Effect in Two-Dimensional Sn2P2S6 Semiconductor for Polarization-Sensitive Photodetection.

A two-dimensional (2D) ferroelectric semiconductor, which is coupled with photosensitivity and room-temperature ferroelectricity, provides the possibility of coordinated conductance modulation by both electric field and light illumination and is promising for triggering the revolution of optoelectronics for monolithic multifunctional integration. Here, we report that semiconducting Sn2P2S6 crystals can be achieved in a 2D morphology using a chemical vapor transport approach with the assistant of space confinement and experimentally demonstrate the robust ferroelectricity in atomic-thin Sn2P2S6 nanosheet at room temperature. The intercorrelated programming of ferroelectric order along out-of-plane (OOP) and in-plane (IP) directions enables a tunable bulk photovoltaic (BPV) effect through multidirectional electrical control. By combining the capability of anisotropic in-plane optical absorption, a highly integrated Sn2P2S6 optoelectronic device vertically sandwiched with graphene electrodes yields the polarization-dependent open-circuit photovoltage with a dichroic ratio of 2.0 under 405 nm light illumination. The reintroduction of ferroelectric Sn2P2S6 to the 2D asymmetric semiconductor family provides possibilities to hardware implement of the self-powered polarization-sensitive photodetection and spotlights the promising applications for next-generation photovoltaic devices.