How do I export tikzpictures to png for use in PowerPoint?

Question

I have made quite a few figures for my thesis in LaTeX. I now want to export about five of those figures as .png with a clear background, so I can use them in my PowerPoint presentation. I'm using TexStudio with MikTex. I've found some old posts about this (TeX to image over command line, How can I create a transparent background in a logo?, how to remove the background for png picture, Making an image with a transparent background), but none seem to answer my question.

Example figure:

\PassOptionsToPackage{table,dvipsnames,svgnames}{xcolor}
\documentclass[11pt, twoside, a4paper]{report}
\usepackage[inner = 30mm, outer = 20mm,  top = 30mm, bottom = 20mm, headheight = 13.6pt]{geometry}
\usepackage{tikz}
\usepackage[pdfpagelayout=TwoPageRight]{hyperref}
\usepackage[export]{adjustbox}
%\usepackage{showframe}
\hypersetup{colorlinks=true, linktoc=all, allcolors=green!30!black,}

\usepackage{pgfplots}
\pgfplotsset{
    compat=1.16,
    %made the beginnings of a second axis style, because I figured it needs to be different for grouped
    my second axis style/.style={
    width=\linewidth,
    height=0.35\linewidth,
    bar width=0.2, %<- changed
    enlarge x limits={abs=0.45},    % <-- changed to absolute coordinates
    ymin=0,
    legend style={
        at={(0.5,1.15)},    % <-- adapted
        anchor=north,       % <-- changed from `north'
        legend columns=3,
    },
    ylabel={PR\textsubscript{A}},
    xtick=data,
    axis lines*=left,
    ymajorgrids,
    %
    table/x=x,
    },
    % created a style for the common `ybar' options
    my second ybar style/.style={
        ybar,
        my ybar legend,            % <-- change legend image accordingly
        #1!50!black,
        fill=white!70!black,, %<- changed back
        nodes near coords,      % <-- moved from `axis' options here
        % state absolute positions for the `nodes near coords'
        scatter/position=absolute,
        node near coords style={
            % state where the nodes should appear
            at={(\pgfkeysvalueof{/data point/x},0.5*\pgfkeysvalueof{/data point/y})},
            anchor=center,rotate=90, %<-added
            % make the font a bit smaller
            font=\footnotesize,
            /pgf/number format/.cd,
            fixed,
            precision=2,
            zerofill,
        },
    },
    my ybar legend/.style={
        /pgfplots/legend image code/.code={
            \draw [
            ##1,
            /tikz/.cd,
            yshift=-0.25em,
            ] (0cm,0cm) rectangle (3pt,0.8em);
        },
    },
}



%data for the grouped bar chart
\pgfplotstableread{
    x          SP_cSi_2_3   SP_cSi_2_4  Reference
    1   0.500   0.627   0.868
    2   0.781   0.778   0.859
    3   0.819   0.868   0.871
    4   0.732   0.824   0.876
    5   0.853   0.873   0.954
    6    0.813   0.838   0.940
    7    0.712   0.759   0.876
    8    0.864   0.894   0.887
    9    0.465   0.614   0.891
}{\loadedtablesppr}


\begin{document}

    \begin{figure}
        \begin{tikzpicture}
        \begin{axis}[my second axis style,
        ybar,
        ylabel={PR\textsubscript{A}},
        xtick= data,
        ]
        \addplot [my second ybar style=blue!50!black,] table [y=SP_cSi_2_3] {\loadedtablesppr};
        \addplot [my second ybar style=orange!50!black,] table [y=SP_cSi_2_4] {\loadedtablesppr};
        \addplot [my second ybar style=red!50!black,] table [y=Reference] {\loadedtablesppr};
        \legend{Floating 2.3~~ , Floating 2.4~~ , Reference}
        \end{axis}
        \end{tikzpicture}
    \end{figure}

\end{document}

Is there a command like \savefig{'my_export_image.png', clear = True}?