Precise Atomic Structure Regulation of Single-Atom Platinum Catalysts toward Highly Efficient Hydrogen Evolution Reaction.

Noble metal single-atom-catalysts (SACs) have demonstrated significant potential to improve atom utilization efficiency and catalytic activity for hydrogen evolution reaction (HER). However, challenges still remain in rationally modulating active sites and catalytic activities of SACs, which often results in sluggish kinetics and poor stability, especially in neutral/alkaline media. Herein, precise construction of Pt single atoms anchored on edge of 2D layered Ni(OH)2 (Pt-Ni(OH)2-E) is achieved utilizing in situ electrodeposition. Compared to the single-atom Pt catalysts anchored on the basal plane of Ni(OH)2 (Pt-Ni(OH)2-BP), the Pt-Ni(OH)2-E possesses superior electron affinity and high intrinsic catalytic activity, which favors the strong adsorption and rapid dissociation toward water molecules. As a result, the Pt-Ni(OH)2-E catalyst requires low overpotentials of 21 and 34 mV at 10 mA cm-2 in alkaline and neutral conditions, respectively. Specifically, it shows the high mass activity of 23.6 A mg-1 for Pt at the overpotential of 100 mV, outperforming the reported catalysts and commercial Pt/C. This work provides new insights into the rational design of active sites for preparing high-performance SACs.

AURKB targets DHX9 to promote hepatocellular carcinoma progression via PI3K/AKT/mTOR pathway.

Aurora kinase B (AURKB) is known to play a carcinogenic role in a variety of cancers, but its underlying mechanism in liver cancer is unknown. This study aimed to investigate the role of AURKB in hepatocellular carcinoma (HCC) and its underlying molecular mechanism. Bioinformatics analysis revealed that AURKB was significantly overexpressed in HCC tissues and cell lines, and its high expression was associated with a poorer prognosis in HCC patients. Furthermore, downregulation of AURKB inhibited HCC cell proliferation, migration, and invasion, induced apoptosis, and caused cell cycle arrest. Moreover, AURKB downregulation also inhibited lung metastasis of HCC. AURKB interacted with DExH-Box helicase 9 (DHX9) and targeted its expression in HCC cells. Rescue experiments further demonstrated that AURKB targeting DHX9 promoted HCC progression through the PI3K/AKT/mTOR pathway. Our results suggest that AURKB is significantly highly expressed in HCC and correlates with patient prognosis. Targeting DHX9 with AURKB promotes HCC progression via the PI3K/AKT/mTOR pathway.

Beneficial effects of maintaining liver function during hepatic arterial infusion chemotherapy combined with tyrosine kinase and programmed cell death protein-1 inhibitors on the outcomes of patients with unresectable hepatocellular carcinoma.

BACKGROUND AND AIM: Combination therapy is the primary treatment for unresectable hepatocellular carcinoma (u-HCC). The hepatic functional reserve is also critical in the treatment of HCC. In this study, u-HCC was treated with combined hepatic arterial infusion chemotherapy (HAIC), tyrosine kinase inhibitors (TKIs), and programmed cell death protein-1 (PD-1) inhibitors to analyze the therapeutic response, progression-free survival (PFS), and safety. METHODS: One hundred sixty-two (162) patients with u-HCC were treated by combination therapy of HAIC, TKIs, and PD-1 inhibitors. PFS was assessed by Child-Pugh (CP) classification subgroups and the change in the CP score during treatment. RESULTS: The median PFS was 11.7 and 5.1 months for patients with CP class A (CPA) and CP class B (CPB), respectively (p = 0.013), with respective objective response rates of 61.1 and 27.8% (p = 0.002) and conversion rates of 16 and 0% (p = 0.078). During treatment, the CP scores in patients with CPA worsened less in those with complete and partial response than in those with stable and progressive disease. In the CP score 5, patients with an unchanged CP score had longer PFS than those with a worsened score (Not reached vs. 7.9 months, p = 0.018). CPB was an independent factor negatively affecting treatment response and PFS. Patients with CPA responded better to the combination therapy and had fewer adverse events (AEs) than those with CPB. CONCLUSIONS: Thus, triple therapy is more beneficial in patients with good liver function, and it is crucial to maintain liver function during treatment.

Bias-dependent photoresponse of Td-WTe2grown by Chemical Vapor Deposition.

The type-II Weyl semimetal Td-WTe2is one of the wonder materials for high-performance optoelectronic devices. We report the self-powered Td-WTe2photodetectors and their bias-dependent photoresponse in the visible region (405 nm, 520 nm, 638 nm) driven by the bulk photovoltaic effect (BPE). The device shows the responsivity of 15.8 mAW-1and detectivity of 5.2×109Jones at 520 nm. Besides, the response time of the WTe2photodetector shows a strong bias-voltage dependent property. This work offers a physical reference for understanding the photoresponse process of Td-WTe2photodetectors.

Complement inhibition alleviates donor brain death-induced liver injury and posttransplant cascade injury by regulating phosphoinositide 3-kinase signaling.

Brain death (BD) donors are the primary source of donor organs for liver transplantation. However, the effects of BD on donor livers and outcomes after liver transplantation remain unclear. Here, we explored the role of complement and the therapeutic effect of complement inhibition in BD-induced liver injury and posttransplantation injury in a mouse BD and liver transplantation model. For complement inhibition, we used complement receptor 2 (CR2)-Crry, a murine inhibitor of C3 activation that specifically targets sites of complement activation. In the mouse model, BD resulted in complement activation and liver injury in donor livers and a cascade liver injury posttransplantation, mediated in part through the C3a-C3aR (C3a receptor) signaling pathway, which was ameliorated by treatment with CR2-Crry. Treatment of BD donors with CR2-Crry improved graft survival, which was further improved when recipients received an additional dose of CR2-Crry posttransplantation. Mechanistically, we determined that complement inhibition alleviated BD-induced donor liver injury and posttransplant cascade injury by regulating phosphoinositide 3-kinase (PI3K) signaling pathways. Together, BD induced donor liver injury and cascade injury post-transplantation, which was mediated by complement activation products acting on PI3K signaling pathways. Our study provides an experimental basis for developing strategies to improve the survival of BD donor grafts in liver transplantation.

Thermally Reversible Cross-Linking of Recyclable Polyamide Materials Based on Schiff Base and Diels-Alder Reactions.

Recyclability of cross-link polymer materials is essential to alleviate environmental pollution caused by discarded or damaged polymers. Herein, a facile method for producing recyclable polyamide materials is developed. Linear polymer chains are constructed by Schiff base reaction between glutaraldehyde (GD) and furandiamine (FD). The linear polymer chains are crosslinked by bismaleimide (BM) to give rise to polyamide material, named GF-BMs. The resulting GF-BMs polyamide material possesses strong tensile strength (78 MPa) and good solvent resistance from room temperature to 135 °C. Especially, the thermally reversible Diels-Alder covalent bonds and dynamic imine bonds in the polymer network have a synergistic effect on fast-reprocessing, self-healing, and recyclability, which provides a new idea for recyclable materials.

Tetramethylpyrazine ameliorates hepatic fibrosis through autophagy-mediated inflammation.

BACKGROUND: Imbalanced immune response and hepatic fibrosis are key factors related to the progression of chronic liver diseases. Tetramethylpyrazine (TMP), a natural alkaloid, has been widely used for treating liver injury. In this study, we explored the effect of TMP on hepatic fibrosis and the related mechanisms regulating autophagy. METHODS: A rat model of hepatic fibrosis and a model using an hepatic stellate cell line (HSC-T6) were created using CCl4 and platelet-derived growth factor (PDGF). Staining with haematoxylin and eosin (HE), Masson's stain, and TUNEL were performed for pathological diagnosis. ELISA, Western blotting, and immunofluorescence analyses were conducted to determine the expression levels of the specific markers for fibrosis, autophagy, inflammation, and signalling pathways. RESULTS: TMP treatment significantly rescued pathological injury and hepatic fibrosis. It also alleviated imbalances in the immune system, accumulation of extracellular matrix, and autophagy signals in hepatic fibrosis. At the same time, we found that application of the autophagy inducer rapamycin enhanced the therapeutic effect of TMP, whereas the autophagy inhibitor 3-methyladenine, PI3K pathway inhibitor LY294002, and AKT pathway agonist SC79 did the opposite. CONCLUSIONS: TMP exerts therapeutic effects in hepatic fibrosis mainly through promoting autophagy to ameliorate inflammation by inhibiting the AKT-mTOR signalling pathway, providing a new perspective for the treatment of chronic liver diseases.

Lattice vibration characteristics in layered InSe films and the electronic behavior of field-effect transistors.

Understanding how temperature affects the structural and electronic properties for two-dimensional (2D) semiconductors could promote the application and development of nanoelectronic devices. Here, the temperature dependence of lattice structure for indium selenide (InSe) nanosheets and the corresponding electronic properties of 3 nm indium-deposited InSe field-effect transistors (FETs) are systematically demonstrated. Analyses of Raman spectra suggest that the difference of phonon frequency (Δω) for the A[Formula: see text] mode is found to be 3.14 cm-1, which is larger than that of the E[Formula: see text] mode due to the stronger electron-phonon coupling for the A[Formula: see text] mode. The device performance based on indium-deposited InSe is systematically explained using Kelvin probe force microscopy (KPFM) and the predicted energy band structure. Furthermore, FETs based on temperature and variable thickness InSe flakes are designed as applicable devices. Our findings are of fundamental importance to explain the underlying physics in intrinsic InSe transistors and improve further applications.

Effects of composition and temperature on the exciton emission behaviors of Mo(S x Se1-x )2 monolayer: experiment and theory.

Exploring the excitonic behavior of two-dimensional (2D) alloys is of great significance, which not only could promote the understanding of fundamental photophysics in optoelectric devices, but could also guide the functional improvement of future applications. Here, we demonstrate the controllable synthesis of monolayer Mo(S x Se1-x )2 nanosheets using a one-step chemical vapor deposition method and systematical investigation on the exciton emission characteristics based on the temperature-dependent photoluminescence spectroscopy (PL) experiments. As a result, the tunable bandgap of Mo(S x Se1-x )2 alloys between 1.52 and 1.85 eV can be achieved, which is consistent with the theoretical results calculated by the ab initio density function theory. Besides, both the exciton and trion behaviors in Mo(S x Se1-x )2 are observed from the PL spectra at T = 80 K. More intriguingly, the differences between the emission energy of exciton and trion (ΔE), known as the dissociation energy of the trion, are positively correlated to the concentrations of the sulfur (S) elements, which is also proved by the theoretical calculation. Combining the experimental and theoretical results, the phenomena can be explained by the reduced dielectric screening effect and the increasing Fermi energy (E F) along with the increasing of sulfur in Mo(S x Se1-x )2 nanosheets, jointly leading to the increase of ΔE. Furthermore, the evolutions of ΔE in Mo(S x Se1-x )2 alloys as a function of temperature have been also discovered, which lay the foundation for the potential uses of 2D alloys in optoelectronic devices.

Enhanced photovoltaic response of lead-free ferroelectric solar cells based on (K,Bi)(Nb,Yb)O3 films.

Herein, we firstly present the (K,Bi)(Nb,Yb)O3 inorganic ferroelectric photovoltaic (FPV) film, in which a nearly ideal bandgap of ∼1.45 eV in the center of the solar spectrum and the co-existence of oxygen vacancies as well as ferroelectric polarization were confirmed. Furthermore, a novel cell structure is successfully fabricated by combining charge-transporting TiO2 nanoparticles, the perovskite sensitizer and a light-absorbing oxide hole p-type NiO conductor to realize a 1 V open circuit voltage, which can be increased to 1.56 V by adjusting the test bias near the coercive voltage. Additionally, under simulated standard AM 1.5G illumination, a fill factor of 86% and a power conversion efficiency of 0.85% are achieved via oxygen vacancy electromigration and polarization switching modulation. It is shown that the obtained power conversion efficiency is one to three orders of magnitude higher than those of pure BiFeO3 and Pb(Zr,Ti)O3. The enhanced PV effects are well elucidated using the transformation from a Schottky-like barrier to Ohmic contacts caused by polarization switching and oxygen vacancies. Building upon the above studies, deep insights into the bandgap tunability and PV effects in ferroelectric films with high oxygen vacancy concentration are provided and will facilitate a new versatile route for exploring high PV performance based on inorganic ferroelectric films.

MicroRNA-329-mediated PTTG1 downregulation inactivates the MAPK signaling pathway to suppress cell proliferation and tumor growth in cholangiocarcinoma.

Cholangiocarcinoma (CCA) is a severe malignancy usually producing a poor prognosis and high mortality rate. MicroRNAs (miRNAs) have been reported in association with CCA; however, the role miR-329 plays in the CCA condition still remains unclear. Therefore, this study was conducted to explore the underlying mechanism of which miR-329 is influencing the progression of CCA. This work studied the differential analysis of the expression chips of CCA obtained from the Gene Expression Omnibus database. Next, to determine both the expression and role of pituitary tumor transforming gene-1 (PTTG1) in CCA, the miRNAs regulating PTTG1 were predicted. In the CCA cells that had been intervened with miR-329 upregulation or inhibition, along with PTTG1 silencing, expression of miR-329, PTTG1, p-p38/p38, p-ERK5/ERK5, proliferating cell nuclear antigen (PCNA), Cyclin D1, Bcl-2-associated X protein (Bax), B-cell CLL/lymphoma 2 (Bcl-2), and caspase-3 were determined. The effects of both miR-329 and PTTG1 on cell proliferation, cell-cycle distribution, and apoptosis were also assayed. The miR-329 was likely to affect the CCA development through regulation of the PTTG1-mediated mitogen-activated protein kinase (MAPK) signaling pathway. The miR-329 targeted PTTG1, leading to inactivation of the MAPK signaling pathway. Upregulation of miR-329 and silencing of PTTG1 inhibited the CCA cell proliferation, induced cell-cycle arrest, and subsequently promoted apoptosis with elevations in Bax, cleaved caspase-3, and total caspase-3, but showed declines in PCNA, Cyclin D1, and Bcl-2. Moreover, miR-329 was also found to suppress the tumor growth by downregulation of PTTG1. To summarize, miR-329 inhibited the expression of PTTG1 to inactivate the MAPK signaling pathway, thus suppressing the CCA progression, thereby providing a therapeutic basis for the CCA treatment.

Probing Effective Out-of-Plane Piezoelectricity in van der Waals Layered Materials Induced by Flexoelectricity.

Many van der Waals layered 2D materials, such as h-BN, transition metal dichalcogenides (TMDs), and group-III monochalcogenides, have been predicted to possess piezoelectric and mechanically flexible natures, which greatly motivates potential applications in piezotronic devices and nanogenerators. However, only intrinsic in-plane piezoelectricity exists in these 2D materials and the piezoelectric effect is confined in odd-layers of TMDs. The present work is intent on combining the free-standing design and piezoresponse force microscopy techniques to obtain and directly quantify the effective out-of-plane electromechanical coupling induced by strain gradient on atomically thin MoS2 and InSe flakes. Conspicuous piezoresponse and the measured piezoelectric coefficient with respect to the number of layers or thickness are systematically illustrated for both MoS2 and InSe flakes. Note that the promising effective piezoelectric coefficient (deff 33 ) of about 21.9 pm V-1 is observed on few-layered InSe. The out-of-plane piezoresponse arises from the net dipole moment along the normal direction of the curvature membrane induced by strain gradient. This work not only provides a feasible and flexible method to acquire and quantify the out-of-plane electromechanical coupling on van der Waals layered materials, but also paves the way to understand and tune the flexoelectric effect of 2D systems.

Large-Scale Growth and Field-Effect Transistors Electrical Engineering of Atomic-Layer SnS2.

2D layers of metal dichalcogenides are of considerable interest for high-performance electronic devices for their unique electronic properties and atomically thin geometry. 2D SnS2 nanosheets with a bandgap of ≈2.6 eV have been attracting intensive attention as one potential candidate for modern electrocatalysis, electronic, and/or optoelectronic fields. However, the controllable growth of large-size and high-quality SnS2 atomic layers still remains a challenge. Herein, a salt-assisted chemical vapor deposition method is provided to synthesize atomic-layer SnS2 with a large crystal size up to 410 µm and good uniformity. Particularly, the as-fabricated SnS2 nanosheet-based field-effect transistors (FETs) show high mobility (2.58 cm2 V-1 s-1 ) and high on/off ratio (≈108 ), which is superior to other reported SnS2 -based FETs. Additionally, the effects of temperature on the electrical properties are systematically investigated. It is shown that the scattering mechanism transforms from charged impurities scattering to electron-phonon scattering with the temperature. Moreover, SnS2 can serve as an ideal material for energy storage and catalyst support. The high performance together with controllable growth of SnS2 endow it with great potential for future applications in electrocatalysis, electronics, and optoelectronics.

Three-dimensional porous Co3O4-CoO@GO composite combined with N-doped carbon for superior lithium storage.

Transition metal oxides (TMOs) as anode materials have potential for lithium-ion batteries (LIBs). However, the poor rate capacity and cycle stability restrict its application. Herein, we demonstrate a facile one-step hydrothermal method to construct a three-dimensional porous conductive network structure, which consists of thin-layered graphene, ultrafine Co3O4-CoO nanoparticles and nitrogen-doped carbon. This unique structure can effectively prevent particle agglomeration and cracking caused by volume expansion, provide fast passage for lithium ion/electron transport during cycling and improve the electrical conductivity of the electrode. Moreover, the electrochemical kinetic analysis proves that this is a process dominated by pseudocapacitive behavior. Consequently, the N-C@Co3O4-CoO@GO hybrid electrode delivers an ultrahigh capacity of 1 273.1 mA h g-1 at 0.1 A g-1 and superior rate performance (725.1 mA h g-1 at 5 A g-1). Additionally, it exhibits a high reversible cycling capacity of 787.4 mA h g-1 at 1 A g-1 over 600 cycles and even maintains excellent cycling stability for a ultra-long cycles at 5 A g-1. This work provides a feasible strategy for fabricating the N-C@Co3O4-CoO@GO composite as a promising high-performance TMOs anode for LIBs.

Pseudocapacitive Li-ion storage boosts high-capacity and long-life performance in multi-layer CoFe2O4/rGO/C composite.

Due to the intrinsic low electrical conductivity and large volume expansion of the CoFe2O4 based active materials, designing more novel structures is still one of the most important challenges for its lithium ion battery application. In this work, the CoFe2O4/reduced graphene oxide/carbon (CFO/rGO/C) composite with integrated multi-layer structure has been synthesized through a facial two-step hydrothermal method. Benefiting from the introduction of the graphene network and amorphous carbon coating layer, as well as the accompanying synergistic effect, this composite can exhibit fast and reversible lithium intercalation/deintercalation reactions. With the aid of a surface-induced capacitive process, the CFO/rGO/C composite delivers a superior specific capacity (945 mA h g-1 at 0.1 A g-1) and excellent long-term cyclic stability (421 mA h g-1 at 4 A g-1 with closely 100% Coulombic efficiency after 2000 cycles). Significantly, at a high current density of 1 A g-1, the reversible capacity exhibits a rapid increasing after 100 cycles and finally shows an ultra-high-capacity of 1430 mA h g-1 over 500 cycles. This method could be generalized to the preparation of other similar transition metal oxide-based materials for the development of high-performance energy storage systems.

Probing electromechanical behaviors by datacube piezoresponse force microscopy in ambient and aqueous environments.

For assisting the in-depth investigations of widespread electromechanical phenomena in functional materials, piezoresponse force microscopy (PFM) has gradually evolved to realize full information-flow acquisition and fit the conductive liquid working environments. Here, we designed data cube (DCUBE) based PFM to collect the electromechanical effect into a high-dimensional array of piezoresponse by adding ac bias with a wide range of frequencies to the probe. The electromechanical and mechanical spectra can be consecutively extracted at each pixel in the intermittent-contact mode. High-resolution ferroelectric domains of the poled LiNbO3 were mapped, corresponding to the ideal phase contrasts of about 180° in air, decane, and deionized water. Rich information detection and non-contact mode in DCUBE-PFM bring many merits on the electromechanical characterizations, especially for elastic-inhomogeneous surfaces and soft materials. Moreover, we systematically reveal the Debye screening effect and time-resolved field-oriented ion dynamics, which play crucial roles in the reduction of PFM spatial resolution in electrolytes. These physical discussions provide strategies to further realize high-resolution electromechanical imaging in highly conductive liquid environments.

Free-anchored Nb2O5@graphene networks for ultrafast-stable lithium storage.

Orthorhombic Nb2O5 (T-Nb2O5) has structural merit but poor electrical conductivity, limiting their applications in energy storage. Although graphene is frequently adopted to effectively improve its electrochemical properties, the ordinary modified methods cannot meet the growing demands for high-performance. Here, we demonstrate that different graphene modified routes play a vital role in affecting the electrochemical performances of T-Nb2O5. By only manual shaking within one minute, Nb2O5 nano-particles can be rapidly adsorbed onto graphene, then the free-anchored T-Nb2O5@graphene three-dimensional networks can be successfully prepared based on hydrogel method. As for the application in lithium-ion batteries, it performs outstanding rate character (129 mA h g-1 (25C rate), 110 mA h g-1 (50C rate) and 90 mA h g-1 (100C rate), correspond to 79%, 67% and 55% capacity of 0.5C rate, respectively) and excellent long-term cycling feature (∼70% capacity retention after 20000 cycles). Moreover, it still maintains similar ultrafast-stable lithium storage performances when Cu foil is substituted by Al foil as current collector. In addition, relevant kinetics mechanisms are also expounded. This work provides a versatile strategy for the preparation of graphene modified Nb2O5 or other types of nanoparticles.

Facile fabrication of 3D porous MnO@GS/CNT architecture as advanced anode materials for high-performance lithium-ion battery.

To overcome inferior rate capability and cycle stability of MnO-based anode materials for lithium-ion batteries (LIBs), we reported a novel 3D porous MnO@GS/CNT composite, consisting of MnO nanoparticles homogeneously distributed on the conductive interconnected framework based on 2D graphene sheets (GS) and 1D carbon nanotubes (CNTs). The distinctive architecture offers highly interpenetrated network along with efficient porous channels for fast electron transfer and ionic diffusion as well as abundant stress buffer space to accommodate the volume expansion of the MnO nanoparticles. The MnO@GS/CNT anode exhibits an ultrahigh capacity of 1115 mAh g-1 at 0.2 A g-1 after 150 cycles and outstanding rate capacity of 306 mAh g-1 at 10.0 A g-1. Moreover, a stable capacity of 405 mAh g-1 after 3200 cycles can still be achieved, even at a large current density of 5.0 A g-1. When coupled with LiMn2O4 (LMO) cathode, the LMO [Formula: see text] MnO@GS/CNT full cell characterizes an excellent cycling stability and rate capability, indicating the promising application of MnO@GS/CNT anode in the next-generation LIBs.

In situ exploration of the thermodynamic evolution properties in the type II interface from the WSe2-WS2 lateral heterojunction.

The mutual interaction of the type II heterointerface can be very susceptible to the variation of electron states, introducing differences into the band structure and the band alignment in comparison to their pristine states. Here, the thermal evolution of the exciton transition and electronic properties inside the covalently bonded type II interface of the atomically planar WSe2-WS2 lateral heterojunction has been studied. With the aid of luminescence and electronic evolution, it was found that the coupling at the heterointerface is strong, and that the change in the photon-electron transition with temperature is weak. Meanwhile, by employing some quantitative computational methods, the temperature variation of the extracted built-in electric field at the interface is unexpectedly pronounced, resulting from the thermodynamical spanning behaviors of the electrons, as well as the strains generated by the difference in the thermal expansion coefficient between the structural lattice. In addition, the electric contact at the interface shows a negative temperature correlation. The present findings provide a vital contribution to the photo-electron interaction-based application and evaluation paths of the electric contact in two-dimensional transition metal dichalcogenide-based devices.

Direct Observation of Landau Level Resonance and Mass Generation in Dirac Semimetal Cd3As2 Thin Films.

Three-dimensional topological Dirac semimetals have hitherto stimulated unprecedented research interests as a new class of quantum materials. Breaking certain types of symmetries has been proposed to enable the manipulation of Dirac fermions, and that was soon realized by external modulations such as magnetic fields. However, an intrinsic manipulation of Dirac states, which is more efficient and desirable, remains a significant challenge. Here, we report a systematic study of quasi-particle dynamics and band evolution in Cd3As2 thin films with controlled chromium (Cr) doping by both magneto-infrared spectroscopy and electrical transport. We observe the √B relation of inter-Landau-level resonance in Cd3As2, an important signature of ultrarelativistic massless state inaccessible in previous optical experiments. A crossover from quantum to quasi-classical behavior makes it possible to directly probe the mass of Dirac fermions. Importantly, Cr doping allows for a Dirac mass acquisition and topological phase transition enabling a desired dynamic control of Dirac fermions. Corroborating with the density-functional theory calculations, we show that the mass generation can be explained by the explicit C4 rotation symmetry breaking and the resultant Dirac gap engineering through Cr substitution for Cd atoms. The manipulation of the system symmetry and Dirac mass in Cd3As2 thin films provides a tuning knob to explore the exotic states stemming from the parent phase of Dirac semimetals.